A123 Systems and NSTAR to Launch Advanced Energy Storage Pilot Project

A123 Systems (Nasdaq: AONE), a developer and manufacturer of advanced Nanophosphate lithium ion batteries and systems, announced that it is launching a pilot project with NSTAR to study and showcase the performance and reliability benefits of implementing A123's Grid Storage Battery (GBS) within a suburban electric grid. The system, NSTAR's first battery energy storage project, is proposed for installation at a substation in Medway, Mass. and is expected to be operational in 2012.

"We’re very interested in learning more about how advanced energy storage can help continue to improve electric service reliability for our customers," said Lawrence Gelbien, vice president of engineering at NSTAR. "Launching this pilot project with A123 will allow us to gain invaluable hands-on experience with clean, efficient energy storage technology and, ultimately, it will help determine how we can utilize larger-scale energy storage projects on our system."

Under the terms of the agreement, one of A123's two-megawatt (2MW) GBS solutions is proposed to be interconnected to the power grid at NSTAR's substation in Medway. It will be owned and operated by A123, and will be designed to provide area regulation services, which are used to address momentary differences between electric power supply and demand. A123 expects to earn revenue from these area regulation services from ISO-New England (ISO-NE) as part of the Alternative Technology Regulation (ATR) Pilot Program, which allows "non-generating resources" such as advanced energy storage systems to receive compensation for area regulation and other ancillary services. In addition, the pilot project is expected to allow A123 to learn more about how its GBS performs in real-world applications in order to facilitate further product improvements designed to reduce total cost of ownership.  

"Working with leading utilities like NSTAR enables us to showcase the economic and operational viability of our advanced GBS solutions and helps to further validate our position as the leading provider of storage technology for electric grid services," said Robert Johnson, vice president of the Energy Solutions Group at A123 Systems. "We expect that this pilot project will allow us to demonstrate how energy storage can generate revenue for area regulation services. Further, we believe that owning and operating our own real-world storage system will allow us to enhance our product offerings to continue delivering cost-effective, efficient solutions that seamlessly integrate with existing grid infrastructure and technologies."

NREL Reports on Value of CSP with Thermal Energy Storage

A new report, Enabling Greater Penetration of Solar Power via the Use of CSP with Thermal Energy Storage, published by the National Renewable Energy Laboratory says concentrating solar power (CSP) plants with thermal energy storage (TES) can dispatch power even during periods of high demand or reduced solar output. This flexibility could boost the use of other types of renewable energy, such as solar photovoltaic (PV)or wind power, that are generated intermittently, the report notes.

Authors Paul Denholm and Mark Mehos describe how CSP systems with TES address the challenges anticipated as greater levels of variable resources, such as PV and wind, are integrated into the Western Interconnect, the major power grid that extends from western Canada, south to Baja California in Mexico, and eastward over the Rocky Mountains to the Great Plains.

There are two major challenges to economically integrating such variable and uncertain resources into the grid. One is the mismatch between when the sun shines, or the wind blows, and when there is a demand for energy. To address this obstacle, CSP with TES can shift energy production to periods of high demand or reduced solar or wind output.

A second challenge is the limited flexibility of conventional generators, such as fossil-fueled power plants, to accommodate variable generation resources, like PV and wind. In this case, CSP with TES can provide substantial grid flexibility by rapidly changing output, via higher ramp rates, in response to the highly variable net load created by high penetration of solar and wind generation.

The report describes how NREL examined the degree to which CSP may complement PV by performing a set of simulations in the U.S. Southwest. The results indicate the general potential of CSP with TES to enable greater use of solar generation, including additional PV.

The authors state that the preliminary analysis performed in their work will require more advanced grid simulations to verify the actual ability of CSP to act as an enabling technology for other variable generation sources. An important next step will include complete production simulations, using utility-grade software, which consider three things: the realistic performance of the generation fleet, transmission constraints, and actual CSP operation.

Safety Concerns Raised Over GM's Volt Li-ion Batteries

According to a story on Bloomberg, "GM Volt Under U.S. Probe for Batteries," General Motors Co. (GM)’s electric plug-in hybrid Chevrolet Volt is the subject of a U.S. safety probe after its lithium-ion batteries, supplied by LG Chem Ltd. (051910), caught fire in crash tests.

Northwestern U Advances Li-ion Tech

A team of engineers from Northwestern University has created an electrode for lithium-ion batteries that allows the batteries to hold a charge up to 10 times greater than current technology. Batteries with the new electrode also can charge 10 times faster than current batteries. The researchers used a graphene-silicon sandwich.

2020 Strategic Analysis of Energy Storage in California

The California Energy Commission's PIER program released a comprehensive report titled "2020 Strategic Analysis of Energy Storage in California." The report discusses the state of technology, policy, barriers to deployment and suggested reforms. 

The conclusion of the report is that energy storage involves numerous technologies (see below), applications, regulatory entities, and grid processes. Given California's long-term goals for integrating variable renewable energy into the grid and decreasing greenhouse gas emissions, "policy makers must determine how energy storage can best fit with these future grid needs," the report states. "These leaders should begin by identifying the critical grid needs that energy storage technologies could address, developing a method for valuing the various energy storage technologies in these applications, and evaluating the policy options available to them to increase deployment of energy storage where the technologies, market value, and locational and environmental benefits offer the most value compared to the alternatives. With this framework, policy makers can determine how California can achieve an appropriate and cost-effective deployment of energy storage that meets all of the state's energy and environmental goals."

The report also calls out suggested R&D priorities:

• Bulk energy storage demonstrations for variable renewable energy integration (for example, pumped hydro, concentrating solar power, and solar thermal).Field demonstrations of modular energy storage technologies (for example, batteries, flywheels) in various grid applications.
• Evaluation/demonstration of aggregated storage, for example Thermal energy storage HVAC or electric vehicle (EV) batteries, especially in a smart grid scenario.
• Develop simulations, analytical tools, and intelligent control systems for planning, designing, and dispatching energy storage devices for multiple applications and benefits.
• Quantification of costs and benefits of energy storage in grid applications.
• Modeling of the impact of 33 percent renewable energy on California's electricity grid to determine needs for energy storage to support the grid, including sensitivity analysis to address cost variables of storage and other needed energy resources, environmental impacts, and emerging smart grid performance enhancements.

The overall findings part of the report notes that grid operators are already deploying large energy storage technologies, such as pumped hydroelectric and compressed air energy storage (CAES). There are significant challenges that must be solved in order to achieve desired storage goals. These goals include: finding appropriate sites for these facilities, obtaining necessary permits from various agencies and levels of government, overcoming regulatory hurdles associated with environmental review, meeting high capital costs for construction, and addressing a lack of access to transmission lines.
 

Manufacturers are demonstrating modular technologies, such as flywheels and various forms of batteries, in grid applications. Key challenges relate primarily to cost (although the modularity of the technologies may offer promise for cost reduction through volume production), to the ability to manufacture and deploy on a large-scale basis, to durability, and because of limited experience in grid applications.

Electrochemical Energy Storage

Batteries take in electricity from another producing source, convert the electricity to chemical energy, and store it as a liquid or solution. When operators need energy from the battery, an electric charge chemically converts the energy back into electrons, which then move back into a power line on the electric grid.

Batteries used to store power from renewable energy sources must be reliable, durable, and safe. Ultimately, affordability will be a key to widespread deployment. There are several promising battery technologies for grid energy storage applications including advanced lead-acid, lithium-ion, flow, and sodium-sulfur batteries.

Advanced Lead-Acid

During discharge in a traditional lead-acid battery, sulfuric acid reacts with the lead anode (positive electrode) and cathode (negative electrode) to create lead sulfate. The process reverses during charge. This conversion produces a short, powerful burst of energy, such as needed to jump start a vehicle. Over time, a lead-acid battery can lose its charge due to the gradual crystallization and buildup of lead sulfate within the battery's core. The corrosive acid also can eat away at a battery’s core.

Lead-acid batteries are a mature and proven technology in use in a number of applications including frequency regulation, bulk energy storage for variable renewable energy integration, and distributed energy storage systems. Technology development of lead‐acid battery technology is ongoing. Researchers have found that adding carbon to the battery seems to minimize or prevent the detrimental crystallization from occurring, thus improving the life cycle and overall lifespan of the battery. This technology has potential for storing renewable energy, but engineers must work to understand the technology's limitations and to find ways to bring down the cost.

Lithium-Ion

In a Lithium-ion (Li-ion) battery cell, positively charged lithium ions migrate through a liquid electrolyte (fluids that conduct electricity) while electrons flow through an external circuit. Both move back and forth from one side to the other. This movement creates and stores energy. Li-ion batteries store energy in various compounds, composed of layers of different elements, such as lithium, manganese, and cobalt.

Li-ion batteries are most commonly found in consumer products and electric vehicles. The relatively high energy and power capacity offered by Li-ion batteries, when compared to other technologies, has made Li-ion batteries the most promising option for transportation applications such as electric vehicles. Developers are considering and demonstrating Li-ion batteries in the same applications as lead-acid batteries.

Although Li-ion batteries have been a success for small electronics such as cell phones and laptop computers, larger versions are expensive, prone to overheating, and susceptible to electrical shorting. While engineers have made substantial progress over recent years toward improving this technology, they will need to make further advances to extend life, improve safety, and reduce materials cost for this to be an attractive alternative for stationary applications.

Flow Batteries

A flow battery is a type of rechargeable battery that stores electrical energy in two tanks of electrolytes. When operators need energy, they pump liquid from one tank to another. During this slow and steady process, the technology converts the chemical energy from the electrolyte to electrical energy. When operators need to store energy, they reverse the process. The size of the tank and the amount of electrolyte the battery can hold determine the amount of energy the battery can store.

Flow batteries may be good candidates for backup energy storage up to 12 hours. They may also support integration of variable renewable energy. This technology has potential for grid applications if developers can manufacture it in a variety of sizes and make it portable and more affordable.

Sodium-Sulfur

The sodium-sulfur battery uses sulfur combined with sodium to reversibly charge and discharge, using sodium ions layered in aluminum oxide within the battery's core. The battery shows potential to store lots of energy in a small space. In addition, its high energy density and rapid rate of charge and discharge make it an attractive candidate for applications that require short, potent bursts of energy.

Sodium-sulfur batteries are a commercial energy storage technology with applications in electric utility distribution grid support, wind power integration, and high-value electricity services. However, materials are expensive, and safety concerns remain with respect to the high operating temperature of the battery. Researchers believe that modifying the shape of the battery can improve efficiency, lower the operating temperature, and reduce cost.

Mechanical Energy Storage

Operators can store energy in water pumped to a higher elevation using pumped storage methods, in compressed air, or in spinning flywheels.

Pumped hydroelectric uses two water reservoirs, separated vertically. During off-peak hours, operators pump water from the lower reservoir to the upper reservoir. The operators reverse the water flow to generate electricity.

Pumped hydroelectric energy storage is a large, mature, and commercial utility-scale technology that utilities use at many locations in the United States and around the world. This application has the highest capacity of the various energy storage technologies that experts have assessed. However, pumped storage plants generally entail long construction times and high capital expenditure for both construction of the plants and needed transmission lines.

Compressed air energy storage technology stores low cost off‐peak energy, in the form of compressed air, typically in an underground reservoir. Operators then heat the air with the exhaust heat of a standard combustion turbine and release it during peak load hours. Operators convert the heated air to energy through expansion turbines to produce electricity.

Compressed air energy storage systems suffer from reduced roundtrip efficiency associated with the cooling/reheating process. Air cooling between compression stages, although necessary, results in a loss of heat energy. Compressed air energy storage systems also produce carbon dioxide (CO2) emissions from the reheating process, usually performed by direct combustion with natural gas. Some compressed air energy storage systems under development, such as advanced adiabatic compressed air energy storage, use a thermal energy storage unit that absorbs heat from the hot compressed air and saves the heat energy for later use to reheat the air before expansion, thus avoiding CO2 emissions.

Flywheel energy storage works by accelerating a rotor (flywheel) to a very high speed, maintaining the energy in the system as rotational energy. When operators extract energy from the system, they reduce the flywheel’s rotational speed as a consequence of the principle of conservation of energy. Adding energy to the system correspondingly results in an increase in flywheel speed.

Developers have matured flywheel technology through the advent of strong, lightweight materials, microelectronics, and magnetic bearing systems. Manufacturers are currently developing and demonstrating megawatt‐scale flywheel plants with cumulative capacities of 20 megawatts to maintain a uniform quality electricity supply often also termed as frequency regulation applications. Overall, manufacturers have proven flywheels to be an ideal form of energy storage due to their high efficiency, long life cycle, wide range of operating temperature, and higher power and energy density on both a mass and volume basis. FESs still present high costs and technology limitations, including modest energy storage capacity and efficiency losses associated with the bearings.

Thermal Energy Storage

Thermal energy storage comprises a number of technologies that store thermal energy in energy storage reservoirs for later use. Operators can employ them to balance energy demand between daytime and nighttime. Operators maintain the thermal reservoir at a temperature above (hotter) or below (colder) than that of the ambient environment. The applications include concentrating sunlight to produce electricity from solar thermal energy during non-solar periods and the production of ice, chilled water, or salt solution at night, or hot water, which the devices use to cool / heat environments during the day.

Solar Thermal Storage Integration

The integration of thermal energy storage with solar energy offers a direct grid application for thermal energy storage. Unlike solar photovoltaic (PV) generation, concentrating solar power uses the thermal energy of sunlight to generate electricity. An advantage of concentrating solar power is the potential for storing solar thermal energy to be subsequently used during non‐solar periods and to dispatch it as needed. Thermal energy storage allows concentrating solar power to achieve higher annual capacity factors from 25 percent without thermal storage up to 70 percent or more with thermal storage. Large concentrating solar power facilities using molten salt energy storage are in construction and/or operation in Spain and the United States. Plans are underway for facilities offering thousands of megawatts of additional generating capacity that will also use this storage technology.

Recent and ongoing improvements in solar thermal generation technologies, coupled with the need for more renewable sources of energy, have caused an increased interest in concentrating solar power. The key challenges lie in further cost reductions and perfecting designs to store solar heat later into the peak electrical period.

Thermal Storage for Heating, Ventilation, and Air Conditioning (HVAC)

In thermal energy storage systems, a device chills a storage medium during periods of low cooling demand and then uses the stored cooling to meet air-conditioning load or process cooling loads. The system consists of a storage medium, such as a water/ice system in a tank, a packaged chiller or built up refrigeration system, and interconnecting piping, pumps, and controls. Heating, ventilation, and air conditioning (HVAC) thermal energy storage systems shift cooling energy use to nonpeak times.

Thermal energy storage for commercial HVAC systems is a mature technology. The key to maximizing the effectiveness of such systems to shift cooling load and thus support the electric grid is appropriate engineering design and implementation.

Hydrogen as an Energy Storage System

Hydrogen as an energy storage system involves four processes. First, a device must produce hydrogen. In a grid energy storage application, the most appropriate production technology is the electrolysis of water using electricity. Second, after electrolysis produces the hydrogen, a device must store it, either in gaseous or liquid form. Third, in many instances, the hydrogen must be transported by truck or pipeline to a distant location. Fourth, to return electric power to the grid, the devices must convert hydrogen to electricity by either a fuel cell or a combustion engine or gas turbine generator.

The primary limitations of hydrogen energy storage systems include the maturity of the fuel cell technology; the durability of fuel cells and electrolyzers; and the capital cost of fuel cells, electrolyzers, and, to a lesser extent, storage vessels. The scale of fuel cells and electrolyzers with respect to grid storage applications and the efficiency of fuel cells and electrolyzers also limits the use of the technology, with roundtrip (electricity into the system to produce hydrogen relative to the electricity produced by the hydrogen fuel cell) energy efficiencies of 31-35 percent.

Argonne Making Sodium-ion Batteries Worth Their Salt

Although lithium-ion technology dominates headlines in battery research and development, a new element is making its presence known as a potentially powerful alternative: sodium.

Sodium-ion technology possesses a number of benefits that lithium-based energy storage cannot capture, explained Argonne National Labs chemist Christopher Johnson, who is leading an effort to improve the performance of ambient-temperature sodium-based batteries.

Perhaps most importantly, sodium is far more naturally abundant than lithium, which makes sodium lower in cost and less susceptible to extreme price fluctuations as the battery market rapidly expands.

"Our research into sodium-ion technology came about because one of the things we wanted to do was to cover all of our bases in the battery world," Johnson said. "We knew going in that the energy density of sodium would be lower, but these other factors helped us decide that these systems could be worth pursuing."

Argonne chemist Christopher Johnson holds a sodium-ion cathode.

Sodium ions are roughly three times as heavy as their lithium cousins, however, and their added heft makes it more difficult for them to shuttle back and forth between a battery's electrodes. As a result, scientists have to be more particular about choosing proper battery chemistries that work well with sodium on the atomic level.
While some previous experiments have investigated the potential of high-temperature sodium-sulfur batteries, Johnson explained that room-temperature sodium-ion batteries have only begun to be explored. "It's technologically more difficult and more expensive to go down the road of sodium-sulfur; we wanted to leverage the knowledge in lithium-ion batteries that we've collected over more than 15 years," he said.

Because of their reduced energy density, sodium-ion batteries will not work as effectively for the transportation industry, as it would take a far heavier battery to provide the same amount of energy to power a car. However, in areas like stationary energy storage, weight is less of an issue, and sodium-ion batteries could find a wide range of applications.

"The big concerns for stationary energy storage are cost, performance and safety, and sodium-ion batteries would theoretically perform well on all of those measures," Johnson explained.

All batteries are composed of three distinct materials—a cathode, an anode and an electrolyte. Just as in lithium-ion batteries, each of these materials has to be tailored to accommodate the specific chemical reactions that will make the battery perform at its highest capacity. "You have to pick the right materials for each component to get the entire system to work the way it's designed," Johnson said.

To that end, Johnson has partnered with a group led by Argonne nanoscientist Tijana Rajh to investigate how sodium ions are taken up by anodes made from titanium dioxide nanotubes. "The way that those nanotubes are made is very scalable—if you had large sheets of titanium metal, you can form the tubes in a large array," Johnson said. "That would then enable you to create a larger battery."

The next stage of the research, according to Johnson, would involve the exploration of aqueous, or water-based, sodium-ion batteries, which would have the advantage of being even safer and less expensive.

Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation's first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America's scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy's Office of Science.

Nearly 600 Energy Storage Projects Announced or Deployed

A new tracker report from Pike Research indicates that nearly 600 energy storage projects have been announced or deployed worldwide, with a surge of new project activity during the past decade.
"Energy storage offers the opportunity to significantly improve the efficiency of the grid at every level," says research analyst Anissa Dehamna.  "The energy storage market is dynamic, but still immature where most technologies are concerned.  The vast majority of active storage projects are utilizing decades-old pumped hydro storage technologies, but the industry has entered a new period of innovation as a number of market players invest considerable resources to prove emerging technologies such as advanced batteries, compressed air energy storage, flywheels, and thermal storage."

Dehamna adds that the wide variety of technologies, applications, and lead times for installations in this sector can make it difficult for many industry participants to analyze the overall market.  Pike Research's tracker aims to identify key market trends on a holistic basis by systematically compiling the available data on all projects around the world including analysis of site, region, size, status, duration, market segment, applications and funding profiles.

Pike Research's "Energy Storage Tracker" provides a comprehensive database of worldwide energy storage projects, including quantitative and qualitative analysis of key trends within the various application and technology segments.  The tracker provides key facts and figures for each project including capacity, location, primary and secondary applications, technologies utilized, and investment cost where available.

Energy Storage Industry Grows To Integrate Wind, Solar

By Robert Crowe, Contributor. Reprinted with permission from Renewable Energy World.

Grid-scale energy storage is gaining momentum as batteries, flywheels and compressed air systems begin proving they can regulate frequency and ancillary services with the same efficiency of "spinning reserves" from fossil fuel-fired power plants.

"We still hear people say storage isn't ready for primetime, but that isn't the case because we already have 20-MW storage plants being built all over the country," said Brad Roberts, executive director of the Electricity Storage Association (ESA).

As more renewable energy hits the grid, generators and independent system operators are looking to new storage systems to provide emissions-free backup and regulation when intermittency interrupts solar and wind power.


A rendering of how A123 Systems Nanophosphate battery sysetms can be used for energy storage at wind farms. Source: A123 Systems.


"We are interested in the potential of battery storage to be a game changer in our industry in both regulated utilities and commercial businesses," said Greg Efthimiou, spokesman for Duke Energy, which operates more than 1,000 MW of wind farms.

Duke Energy is installing the country's largest battery storage system, a 36-MW unit, near its 153-MW Notrees Windpower Project. The system will regulate frequency and store excess energy for use during peak demand. In Texas, where nearly 11,000 MW of generation comes from wind farms, grid operator Electric Reliability Council of Texas relies on standby gas turbines and steam coal generators to ramp frequency up or down as wind generation changes.

The Notrees battery system is funded by a $22 million grant from the U.S. Department of Energy (DOE) and matching funds from Duke Energy, which will use Austin-based Xtreme Power's proprietary dry cell technology.

Investment, Policy Gains
ESA's Roberts said the $158 million in stimulus earmarked by the DOE for storage research generated $780 million in investments for battery, compressed air, flywheels and other systems.

The storage industry has been calling for creation of an ITC to further stimulate growth. With passage of Assembly Bill No. 2514 in September, California began the process of developing a portfolio standard for energy storage.

Storage technology pulled in $150.3 million in venture capital during the second quarter, according to Ernst & Young. General Compression received the largest percentage, with $54.5 million. The company plans to use General Compression Advanced Energy Storage (GCAES), a unique heat transfer technology, to compress air in underground caverns. Investors include ConocoPhillips, US Renewables Group, Duke Energy and Serious Change L.P.

Compressing air underground has the potential for storage in excess of 100 MW but there are only two such projects in the world: A 290-MW facility built in Huntorf, Germany in 1978, and a 110-MW facility completed in 1991 in McIntosh, AL. And in July Iowa officials and the DOE scrapped the Iowa Stored Energy Park, a facility intended to store up to 270 MW of wind energy in a limestone cavern 3,000 feet underground. Studies showed limitations with air permeability in the site's geology.

CAES Winners, Losers
Compressed Air Energy Storage (CAES) utilizing man-made, above-ground storage tanks has also gained traction with DOE funding. Startup SustainX, Inc. is working with AES Energy Storage to demonstrate a one-hour, 4-MW storage system. SustainX was founded in 2007 by engineers at the Thayer School of Engineering at Dartmouth College. It received $5.39 million DOE grant.

The Arizona Research Institute for Solar Energy (azRISE) at the University of Arizona has been developing a CAES solution for three years. DOE funds will enable azRISE to scale up a 10-kW proof-of-concept prototype (image, below) that will be grid-tied to a 1.6-MW solar power plant.

SOLON Corp., the solar plant's developer, is working with azRISE and Tucson Electric Power (TEP) to demonstrate a variety of storage projects, including lithium ion batteries. "As we see more integration of solar, we want to control storage for our utility customers," said Bill Richardson, SOLON's director of research and development. "The ultimate goal is to make renewable energy plants look like traditional plants with dispatchable energy."

Joseph Simmons, azRISE director, said storage prices are high, particularly for battery systems, but he predicts a breakthrough will come with "intermediate size" compressed air systems that use off-the-shelf storage containers and have capacities of up to 100 kW. The institute's concept, he said, can be scaled up to 1 MW with a coiled natural gas pipeline buried underground.

"I like batteries but they are very expensive," Simmons said. "We expect to see more of a combination of batteries and compressed air storage."

Heat transfer is another issue associated with CAES since air cools when it expands and warms during compression. The azRISE system removes heat from a compressor then stores it in fluid. The system recovers electricity when heat returns to the compressed air before entering an expander. SustainX manages heat by uses an isothermal system to cycle air in hydraulic cylinders.

Price Points Still High
In just three years, the storage industry has grown rapidly from a handful of prototypes to revenue-generating corporations, Roberts said. Current battery technology has a long way to go before renewable energy can be stored and dispatched in meaningful amounts. Meanwhile, revenue is limited to ancillary services, critical observers say. And then there's the price: At $43.6 million, the 36-MW Notrees system costs $1,211 per kilowatt. Others are down to $400. "But the price is still way too high for this market," said Donald R. Sadoway, Professor of Materials Chemistry at MIT.

The leading battery systems are based on lithium ion or sulfur-sodium (NaS) power cells. A multiple-megawatt storage system using these technologies can require thousands of cells.

Sadoway co-founded Liquid Metal Battery Corp., a startup that uses pizza box-sized power cells made with liquid metal and molten salt. Sadoway is banking on his batteries to provide game-changing, cost-effective power storage capacity. "Storage will have to be below $200 per kilowatt if we're going to be major players in the long-term storage firming in renewables without government subsidy," he said.

Pumped-hydro, which accounts for 20 GW of the country's energy storage, can provide 1,000-MW storage systems for $100 per kilowatt-hour, according to The New York Times. It requires massive reservoirs that cost more than $1 billion and take years to construct with ideal geography and abundant water resources. That pretty much rules out the arid Southwest, so researchers like Simmons and Sadoway look to alternatives. (For a primer on Energy Storage Costs, see Sidebar: Understanding Energy Storage Costs, below.)

Sadoway's company received a $6.9 million grant from the Advanced Research Projects Agency-Energy (ARPA-E) as well as seed money from Total, an oil company, and Microsoft Co-Founder Bill Gates. Sadoway said the size of his batteries will broaden grid-scale storage capacity since more liquid will be present per cell than conventional cells.

Lithium Ion Still Popular
"We're starting to see prices come down as we scale up each project," said John Zahurancik, AES Energy Storage vice president. AES Energy Storage is installing a 32-MW lithium ion storage system to regulate the 100-MW Laurel Mountain Wind Farm in West Virginia. Since it was founded in 2007, AES Energy Storage has completed more than 32 MW of storage, and it claims to have 500 MW "in the pipeline."

"We are starting to demonstrate the real commercial competence of storage," Zahurancik said.
Storage is attractive to generators – parent company AES Corp. operates 132 power plants worldwide – because it provides "fuel-free" power during peak hours, Zahurancik said.

Large-scale battery storage is still years away, so revenue streams are limited to ancillary services, which represent a small piece of all sales on the electricity market. The ESA and American Wind Energy Association are lobbying utility regulators who oversee electricity sales to create markets that recognize a premium for emissions-free storage and regulation.

Some systems are growing outside of ancillary services. AES is installing an A123 Systems battery unit capable of providing 20 MW of spinning reserve for 15 minutes in Northern Chile.
"We're moving out of the lab and into large production facilities," said Chris Campbell, vice president of marketing for A123 Systems' Energy Solutions Group.

He said A123 Systems European customers are interested in 100-MWh to 500-MWh storage systems that will help them meet clean air goals. Zahurancik said battery storage devices in the next three years will offer two to four hours of storage for that can transfer nighttime wind energy for peak use. "We're already seeing our market grow like the solar and wind industries," he said.

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Sidebar: Understanding Energy Storage Costs
Energy storage systems are typically quantified in terms of capacity (kilowatts or kW) and generation (kilowatt-hours or kWh), but there are some exceptions. "In the case of energy storage costing, dollars per kilowatt-hour can be very misleading," said Brad Roberts, executive director of the Energy Storage Association.

Battery storage is growing rapidly, but costs remain high, so the industry is striving for average prices to dip below $500 per kWh within three years. "Technologies like lithium ion need to see huge price declines in the next few years which may be possible as electric transportation grows," Roberts said.

The approximate cost of a 1-MW, 6-hour sodium-sulfur (NaS) battery is $3,000 per kW. That translates to a cost of $500 per kWh ($3,000/ 6 hours = $500), Roberts said.

Xtreme Power Chief Development Officer Darrell Hayslip said battery costs are expressed in dollars per kWh when considered "stored energy." Xtreme Power often quotes prices in terms of dollars-per-kilowatt because it markets its dry cell products as a "generating or supply resource," Hayslip said.

Xtreme Power's 36-MW Notrees project is funded by about $22 million U.S. Department of Energy grant and $22 million in matching funds from Duke Energy, which Hayslip said brings the cost to $1,211 per kW ($43.6 million/36,000 kilowatts = $1,200).

Joseph Simmons, director of Arizona Research Institute for Solar Energy (azRISE), estimates a 10-kW compressed air storage system with a $50,000 price tag can generate 30 kilowatt-hours, or three hours of electricity at 33 cents per kilowatt-hour.

Calculations for the University of Arizona system call for use of a 1,000-gallon storage tank. He said the system could be scaled up to 10 MW using coiled pipeline to create 1 million gallons of storage space. Such a system would generate 30 MWh, but price is unknown at this point, he said.

Robert Crowe is a technical writer and reporter based in San Antonio, Texas. He has written for Bloomberg, the Houston Chronicle, Boston Herald, StreetAuthority.com, San Antonio Express-News, Dallas Business Journal, and other publications. He covers renewable energy and sustainability for various publications. As a consultant, he works closely with companies to develop technical materials for renewable energy and sustainability strategies.

Electric Vehicle Batteries: New Report

Over the past few years, the automotive industry has increased its focus on the electric vehicle (EV) market by successfully introducing several new plug-in hybrid and battery electric vehicles as the process of moving away from petroleum based fuels and toward battery power intensifies. These vehicles will rely almost exclusively on lithium ion (Li-ion) batteries, while hybrid vehicles will slowly switch from nickel-metal hydride (NiMH) technology. While the cost of Li-ion batteries is gradually declining, cost still represents a significant hurdle as it accounts for a large portion of total EV cost.

The government subsidies that gave the initial impetus to the electric vehicle market will continue to drive the market in the near term. However, significant reductions in battery cost are imperative for the industry to grow to the $14.6 billion and 28 million kWh market that Pike Research forecasts by 2017. Nearly half of the demand is likely to come from Asia (led primarily by China) while Europe and the United States are likely to constitute 25% and 21% shares respectively.

There are currently more than half a dozen battery chemistries with unique properties for power, energy density, and life cycle performance that are being commercialized. While there is no chemistry that emerges as the clear winner (owing to the tradeoffs in the various properties), initial indications point to a greater interest in the lithium iron phosphate chemistry in the years to come due to its superior performance characteristics coupled with increased safety.

A new report from Pike Research outlines the critical role that governments around the globe will play in establishing the electric vehicle market, and the challenges that manufacturers face in creating an industry that will be able to stand on its own as government influence diminishes. The study examines the key market drivers for the electrification of vehicles, the status of the R&D in batteries, the impact of declining battery production costs on vehicle sales, and the resale of batteries after their useful life in vehicles.

Lithium Technology to Launch a Li Ion Battery Manufacturing JV

Lithium Technology Corporation (ticker symbol:LTHU), a manufacturer of large format cylindrical lithium-Ion cells, has entered into a definitive agreement to launch a joint venture with EnerSys, Inc. (NYSE:ENS) in Germany to produce large format lithium-ion based cells.

EnerSys will lead the joint venture in cooperation with GAIA Akkumulatorenwerke GmbH (GAIA), a unit of LTC. The joint venture will include LTC's contribution of certain intellectual property, and its low volume lithium-ion cell manufacturing capability located in Nordhausen, Germany. LTC will continue to have full access to the Nordhausen facility, its production capability, employees and intellectual property. It is anticipated that the joint venture will commence operations and production on October 17, 2011.

LTC, through its GAIA subsidiary, and EnerSys have had a distribution agreement for the past three years. This joint venture will expand the relationship between the two companies. A new company has been formed, EAS Germany GmbH, which will further the development and production of lithium-ion based solutions for space, naval, marine, renewable energy, and specialty high power applications for EnerSys. The JV will also continue to provide certain products to LTC for its customers in the transportation sector. LTC, through its ownership stake in EAS, will benefit from the market success of EnerSys' global marketing and sales network.

Most LTC customers will continue to deal with LTC as before and see no change to their existing relationship with the company; however, they will benefit from the industrial expertise EnerSys brings to the joint venture. The joint venture allows LTC to focus its efforts on developing its capabilities in the passenger and heavy-duty transportation markets. The intellectual property license to EAS is limited to products manufactured within the Nordhausen facility.

Financing for Crescent Dunes Solar Thermal Project Completed

SolarReserve, a U.S. developer of large-scale solar power projects, has closed financing for the 110 MW Crescent Dunes Solar Energy Project to be built near Tonopah, Nevada. The Crescent Dunes project will the nation's first commercial scale solar power tower with fully integrated energy storage, the largest of its kind in the world, according to the company (artist's rendition shown).

The project is being constructed on federal land operated by the Bureau of Land Management. In November 2010, Interior Secretary Salazar signed the project's thirty-year right-of-way and approval to construct. Construction commenced earlier in September and the project is expected to start operations in late 2013.

As part of the project financing, SolarReserve is joined as investors in the project by ACS Cobra, which is focused on the engineering and construction of power plants and thermal solar facilities, and the equity capital practice of Santander. The project also closed on $737 million in project debt along with a loan guarantee from the U.S. Department of Energy. ACS Cobra's Nevada-based affiliate, Cobra Thermosolar Plants Inc., will act as the general contractor utilizing Nevada and regional subcontractors to perform the work.


1. Sunlight is concentrated and directed from a large field of heliostats to a receiver on a tall tower. 2. Liquid salt from the cold salt tank is pumped through the receiver where it is heated to 1050F. 3. The heated salt from the receiver is stored in the hot salt tank. 4. Hot salt is pumped from the hot salt tank through a steam generator to create steam, which drives a steam turbine, generating electricity. 5. Cold salt at 525F flows back to the cold salt tank.

 The proposed facility will use concentrating solar power (CSP) technology, and be equipped with an integral storage system. The technology generates power from sunlight by focusing energy from a field of sun-tracking mirrors called heliostats onto a central receiver. Liquid salt, which flows similar to water when melted, is circulated through the receiver, collecting the energy gathered from the sun. The heated salt is then routed to an insulated storage tank where it is stored with minimal energy losses. When electricity is to be generated, the hot salt is routed to heat exchangers to produce steam used to generate electricity in a conventional steam turbine cycle. The salt is then sent to the cold salt storage tank, ready to be reheated by the sun and reused the following day. The salt storage technology was demonstrated successfully at the U.S. Department of Energy-sponsored 10-MW Solar Two project near Barstow, California.

European Association for Storage of Energy Launched

A group of Europe's leading players in the energy sector, including manufacturers, utilities and academic bodies, came together in Brussels on September 27 to sign the formal constitution for the creation of the European Association for Storage of Energy (EASE). This international non-profit association is focused on acting as a coherent voice to promote the roles of energy storage as key enabling technologies for Europe's transition towards a sustainable, flexible and stable energy system.

The 13 founding members of EASE are Alstom, DONG Energy A/S, EDF SA, EnBW AG, Enel S.p.A., E.ON AG, GDF SUEZ SA, Hitachi Power Europe GmbH, KEMA BV, RISO DTU, RWE AG, Saft SAS, and Siemens AG.

According to the group's announcement, EASE has been created to provide a single, coherent body of competence and influence that brings together the many diverse groups currently working in the energy storage field. Its main aims are to stimulate the development of innovative energy storage technologies and applications through building a platform for the sharing and dissemination of knowledge and information, and to coordinate national activities. Consequently EASE will act as a sound and visible advocate of energy storage in Europe.

The group notes that effective energy storage can deliver a number of strategic services both on the regulated and deregulated side of the power business, addressing three major challenges: balancing demand and supply, management of transmission and distribution grids, energy efficiency. "In a world where patterns of energy supply and consumption are changing rapidly, especially with the large increasing penetration of renewable energy sources and distributed generation, sustained increases in fossil fuel prices, changing market regulations and stringent environmental targets, there is a considerable pressure on stakeholders to evolve to meet these new demands," EASE notes in a press release.

The founding members have designed EASE as a truly European entity, complementary to the existing European Industrial Initiatives (EIIs) in the frame of SET-Plan and to some Public Private Partnerships (PPPs). The SET-Plan covers a number of relevant areas especially Wind, Solar Energy, Smart Grids, Green Cars, Smart Cities and Efficient Buildings initiatives.

The group said that EASE represents all European participants active in the energy storage arena (but also said it is now looking for new members). It will promote and support analysis and evaluation of the benefits of utilizing energy storage in the broader energy grid. It will also cooperate with other national and international energy storage organisations, including Electricity Storage Association (ESA) in the USA.

EASE will work on technology- and application-related aspects of energy storage such as assessment of storage applications and development of storage technology roadmaps as well as addressing financial, economic and regulatory issues. It plans to work with all relevant groups to discuss and 'ease' the optimal integration of all components into validation projects and business models for a successful transition to a low carbon, safe and sustainable energy infrastructure, and to help establish a coherent master plan for the introduction of energy storage worldwide.

The creation of EASE results from an initiative of the European Commission, looking for a consensual vision of the roles, technologies and potential applications of energy storage within the frame of EU Energy and Climate policy. Following on from an Energy Storage Task Force launched by the European Commission in 2009 and the results of the final workshop, a group of leading European energy players decided to work together to found the new association.

The Paper Battery Company Wins NYSERDA Award

The Paper Battery Company (Troy, NY) received a $1 million award from The New York State Energy Research and Development Authority (NYSERDA) to continue development of a fully printed energy-storage device that is as thin as a piece of paper. NYSERDA's funding will be matched by the company and private investors.

Paper Battery is a three-year-old company located at the Russell Sage College INVEST Incubator. It has designed an ultracapacitor that it claims to be thinner than any product currently in production. The firm's first product line is called the PowerPatch, which is a patternable device, scalable in voltage, energy and power in a single package. The device uses a cellulose-based material to contain and separate the various components, and its thinness and flexibility allows it to fit around the confines of tightly-packed electronic equipment. It also integrates directly into system structural elements such as printed circuit board layers, reducing component count and opening new applications for power distribution and management.

Ultracapacitors are energy-storage devices that give off short bursts of energy and, in one application, are used by computer manufacturers to provide emergency power to allow equipment to finish processing and save critical data changes in the event of a power outage or other problem. The technology also has a variety of clean-energy applications, including hybrid electric cars (for rapid acceleration and regenerative braking), flexible solar panels, and other products that require high power and long charge/discharge cycle lives.

"Ultracapacitors serve a vital role in the clean-energy economy, and Paper Battery's product design make it unique in this growing market," said Francis J. Murray Jr., President and CEO of NYSERDA. "NYSERDA is proud to invest in a company that sits at the exciting intersection of nanotechnology, advanced materials and energy storage." Paper Battery's design captures 30 percent more energy than other ultracapacitors, according to Shreefal Mehta, the company's President and CEO. The product is also safer for the environment because it uses less metals than energy storage devices currently being manufactured. "Thanks to NYSERDA's funding, the company will be able to retool print stations and build a pilot line in order to meet customer requests for samples," said Mehta. "This funding will allow the company to position itself for scaling to commercial production, growth and job creation."

The company, which currently employs four people, expects to hire up to 10 new employees by this time next year, with plans to start commercial manufacturing in 2013. In terms of business strategy, the goal is to positive cash flow by 2015 through direct sales to OEMs as on-board integrated power modules. According to an executive summary on the company's website, technical discussions and tests are ongoing with market leading OEMs. A co-development R&D contract has also been signed with a leading medical diagnostic device company for wearable diagnostic sensor patches. Development partnerships for large consumer portable electronics and for specialty military and medical markets will be explored with commercial partners. The production and technology platform will mature with partnerships for large volume consumer markets (>$500M/yr) and larger format structural sheeting energy storage in transportation and grid applications, according to the company.

Massive Demand for Lithium Ion Batteries Says IHS

The expected proliferation of electrical smart grids during the next decade will generate nearly $6 billion worth of demand by 2020 for lithium ion batteries used mainly in energy storage systems, according to the IHS iSuppli Rechargeable Batteries Special Report. From its starting point in 2012, the market for lithium ion batteries in smart grids is set for rapid growth, as presented in the figure below.

Worldwide revenue from sales of lithium ion batteries for smart grids will surge to $5.98 billion in 2020, up by a factor of more than 80 from $72 million in 2012.

"Smart grids require rechargeable batteries to adjust to fluctuations in demand and to optimize the delivery of electric power throughout the system," said Satoru Oyama, principal analyst for Japan electronics research for IHS. "With their inherent advantages compared to alternative technologies, lithium ion batteries are uniquely suited for use in smart grids. Because of this, lithium ion is set to emerge as the dominant rechargeable battery technology for electrical smart grids during the coming years."

Smart grid energy storage comes in multiple form factors, ranging from single-home systems to a cluster of homes or a building, to uninterruptible power systems for corporate information technology (IT) operations, to large-scale systems used by grid operators. Energy storage is used for purposes running from grid stability to backup power for IT, to extending wind and solar energy capture into the evening, the report notes. An advantage to lithium ion batteries is that they maintain full capacity even after a partial recharge. Furthermore, they are considered to be more environmentally safe than other battery technologies.

Beyond smart grids, lithium ion batteries are employed in a wide range of applications, including mobile handsets, notebook PCs, tablet computers, and hybrid and electric vehicles.

IHS defines a smart grid as a utility electricity delivery system that employs computer and communications technology to improve the flexibility and efficiency of power distribution. In conventional power grids, power flows just one way, going from large-scale power generators to users. Smart grids, in contrast, can accommodate and control electricity that is generated both by big utilities and by individual consumers and businesses. This makes smart grids a key element in utilizing and redistributing the energy generated by solar systems installed by electricity users. Development of smart grids is being spurred by various government initiatives throughout the world. For example, the United States has budgeted $4.5 billion for the purpose. Meanwhile, China is expected to become the largest smart grid market in the world, with $586 billion set to be invested in the electrical power supply infrastructure during the next 10 years.

First U.S. Grid-Tied Solar Energy Storage Goes On-line

The nation's first solar storage facility that is fully integrated into a utility's power grid is now online.
The PNM Prosperity Energy Storage Project, located south of the Albuquerque International Sunport near Mesa Del Sol, can produce 500 kilowatts of power and uses high-tech batteries to create firm and dispatchable energy derived from a renewable energy source. It is the first of 16 smart grid projects partially funded by stimulus monies to be fully operational.

Using 2,158 solar panels, 1,280 advanced lead-acid batteries, smart grid technology and sophisticated metering and monitoring technology, the storage system can automatically smooth the output of the solar panels, making the renewable power more dependable. For example, when a cloud casts a shadow on the solar array, energy output immediately is reduced. The battery and smart grid system work in tandem to instantaneously dispatch energy to fill the gap created by the cloud. In addition, the system can store solar power -- or energy produced by other facilities connected to the PNM grid -- when demand is low. During times of peak customer use, the system then can dispatch the power back into the grid to support demand.

"While PNM has three solar facilities online and two more in the works, the batteries and technology supporting this project create a reliable solar energy resource and can produce power when the sun isn't shining," said Pat Vincent-Collawn, PNM president and CEO. "Without an energy storage component, renewable energy is a limited resource that needs to be backed up by traditional generation facilities. Although this technology is in its early integration stage and additional research and development is needed, the PNM Prosperity Energy Storage Project is a significant first step toward making renewable energy reliable energy."

U.S. Sen. Jeff Bingaman, who serves as chairs of the Senate Energy and Natural Resources Committee, U.S. Rep. Ben Ray Lujan, U.S. Department of Energy representatives and state and local officials are scheduled to speak during a dedication of the facility on Saturday, Sept. 24.

"New Mexico has great potential to be a top producer of solar energy for our country. One key to that success will be our ability to harness solar power for use when the sun is not shining," said Sen. Bingaman. "I applaud the Department of Energy, PNM, and the Electric Power Research Institute for advancing this storage effort, and hope that it will be the first of many similar projects around the country."

U.S. Senator Tom Udall echoed those sentiments, saying, "New Mexico is a leader in renewable energy and smart grid technology, and I congratulate PNM for their success on this project which will help lower the costs and increase the use of renewable energy in New Mexico and across the country."

The genesis of this project began in 2008 when PNM and the Electric Power Research Institute began planning a project to demonstrate smart grid technology in PNM's distribution system. When the U.S. Department of Energy announced its Smart Grid Storage Demonstration Program supported by funds from the American Recovery and Reinvestment Act of 2009, PNM and EPRI quickly reshaped their plans and submitted a proposal to federal officials.

Sen. Bingaman strongly supported the PNM-EPRI proposal in a letter to DOE officials, saying the project "would unlock numerous benefits to the people of New Mexico and the citizens of the United States, including green job creation, development of green manufacturing, and sustainable renewable energy development."

In November 2009, PNM announced it was among the utilities awarded federal funds for a smart grid project, now known as the PNM Prosperity Energy Storage Project. The project features one of the largest combinations of battery storage and photovoltaic energy in the nation and involves extensive research and development of smart grid concepts with EPRI, East Penn Manufacturing Co., Northern New Mexico College, Sandia National Laboratories and the University of New Mexico.

"Our goal is to identify, test and demonstrate the numerous benefits derived from this storage system," said Steve Willard, a PNM engineer and the project's manager. "While construction of the project is completed, our research has just begun. During the next two years, we'll constantly collect data and share our findings with the industry worldwide to help advance energy storage technology."

Other New Mexico companies that had significant contributions to the project include Albuquerque's SCHOTT Solar, and Cameron Swinerton and Positive Energy, both based in Santa Fe.

Saft Opens Advanced Battery Plant in Florida

Saft America opened a factory in Jacksonville, Florida, that will produce advanced lithium-ion batteries to power electric vehicles and other applications. Saft expects to produce 370 megawatt hours of battery power a year – the equivalent of supplying more than 37,000 electric-drive vehicles.

Saft America Incorporated’s Industrial Battery Group won a $95.5 million DOE grant under the American Recovery and Reinvestment Act in 2009 and provided an additional $95.5 million in cost share to build the new 235,000 square foot battery factory capable of manufacturing high quantities of lithium-ion cells, modules, and batteries.

This project is part of the Recovery Act’s $2 billion investments in battery and electric drive component manufacturing, supporting 20 battery and 10 component manufacturing factories. At full scale, these investments will support factories with the capacity to supply more than 500,000 electric drive vehicles. These factories are helping build a domestic electric-drive vehicle industry – the U.S. produced less than 2 percent of the world’s batteries in 2008. By the end of 2012, it is estimated that the U.S. will have the capacity to produce 20 percent of the world’s advanced vehicle batteries. These factories are also lowering costs. By 2013, these factories will help cut battery costs in half, making electric-drive vehicles much more affordable for Americans. Additional DOE investments in R&D will continue this type of innovation well beyond 2015, providing a long-term path for a competitive industry.

Aquion Raises $30 Million for Sodium-Based Battery

Aquion Energy, Inc., a developer and manufacturer of batteries and energy storage systems, closed a $30 million round of venture financing. Foundation Capital led the round with participation from returning investor Kleiner Perkins Caufield & Byers as well as new investors Advanced Technology Ventures (ATV) and TriplePoint Capital.

Aquion Energy, Inc. is a Pittsburgh-based company that is designing and manufacturing a revolutionary type of battery based on the research of Carnegie Mellon University Professor Jay Whitacre, who has developed a novel, sodium-ion, aqueous electrolyte battery (Whitacre is now the chief technology officer at Aquion).

Whitacre's U.S. patent filing gives some background into why it's an attractive energy storage solution.

Small renewable energy harvesting and power generation technologies (such as solar arrays, wind turbines, micro sterling engines, and solid oxide fuel cells) are proliferating, and there is a commensurate strong need for intermediate size secondary (rechargeable) energy storage capability. Batteries for these stationary applications typically store between 1 and 50 kWh of energy (depending on the application) and have historically been based on the lead-acid (Pb-acid) chemistry. Banks of deep-cycle lead-acid cells are assembled at points of distributed power generation and are known to last 1 to 10 years depending on the typical duty cycle.

While these cells function well enough to support this application, there are a number of problems associated with their use, including: heavy use of environmentally unclean lead and acids (it is estimated that the Pb-acid technology is responsible for the release of over 100,000 tons of Pb into the environment each year in the US alone), significant degradation of performance if held at intermediate state of charge or routinely cycled to deep levels of discharge, a need for routine servicing to maintain performance, and the implementation of a requisite recycling program. There is a strong desire to replace the Pb-acid chemistry as used by the automotive industry. Unfortunately the economics of alternative battery chemistries has made this a very unappealing option to date.

Despite all of the recent advances in battery technologies, there are still no low-cost, clean alternates to the Pb-acid chemistry. This is due in large part to the fact that Pb-acid batteries are remarkably inexpensive compared to other chemistries (<$200/kWh), and there is currently a focus on developing higher-energy systems for transportation applications (which are inherently significantly more expensive than Pb-acid batteries).

The Aquion sodium battery works like this:

The charge/discharge processes of the battery is based the transfer of sodium (Na) cations between the active cathode electrode material and the anode electrode, with a Na cation containing electrolyte acting primarily as an ionic conductor between the two electrodes. That is, the cation concentration in the electrolyte stays relatively constant through a charge/discharge cycle. As the system is charged, cations in the electrolyte solution are adsorbed onto the surface of the anode material. At the same time, cations deintercalate from the active cathode material, thus keeping cation electrolyte concentration roughly constant through the charging process. Conversely, as the system is discharged, cations in the electrolyte solution intercalate into the active cathode material. At the same time, cations desorb from the surface of the anode material, thus keeping cation electrolyte concentration roughly constant through the discharge process.



The patent goes on to describe the unique approach that's embodied in the Aquion sodium battery:

The highly-purified solvent-based non-aqueous electrolytes that must be used in energy storage devices, such as batteries, supercapacitors, or hybrid-energy storage systems, is a source of expense. Highly purified solvent-based non-aqueous electrolytes are typically necessary in Li-based systems because Li-ion systems are designed to have a relatively high operating potential, typically between about 3.3 and 4.2 V. Such high operating potentials are problematic for aqueous systems because water is electrolyzed at -1.3 V, so non-aqueous (i.e., solvent-based) electrolytes that are stable to >4 V are needed. This results in several undesirable consequences. First, the conductivity of these solvent-based electrolytes is much lower than water-based electrolytes, so Li-ion batteries are either significantly rate limited, or must be fabricated in such a way that they have very thin porous electrodes. Usually the latter design is selected despite being a much more complicated design with high surface area current collectors, very thin roll-coated electrodes, and a large-area polymer separator. Much of the cost associated with state of the art Li-ion batteries is a result of this design paradigm. Second, the cost of handling and fabrication is elevated since a moisture-free environment must be maintained during battery assembly. Third, a controlled moisture-free fabrication environment is required, which also increases cost and complexity.

In contrast, embodiments of the present invention provide a secondary (rechargeable) energy storage system which uses a water-based (aqueous) electrolyte, such as a Na-based aqueous electrolyte. This allows for use of much thicker electrodes, much less expensive separator and current collector materials, and benign and more environmentally friendly materials for electrodes and electrolyte salts. Additionally, energy storage systems of embodiments of the present invention can be assembled in an open-air environment, resulting in a significantly lower cost of production.

Secondary (rechargeable) energy storage systems of embodiments of the present invention comprise an anode (i.e., negative) electrode, an anode side current collector, a cathode (i.e., positive) electrode, a cathode side current collector, a separator, and a Na-ion containing aqueous electrolyte. Any material capable of reversible intercalation/deintercalation of Na-ions may be used as an active cathode material. Any material capable of reversible adsorption/desorption of Na-ions and can function together with such an active cathode material and an appropriate electrolyte solution may be used as an anode material.

Aquion says that its unique technologies and products provide "compelling" results on key performance factors including cycle/calendar life, round trip efficiency, discharge abuse tolerance, capital costs, maintenance costs, and safety. In addition, Aquion batteries are inherently green and contain no hazardous materials, corrosive acids or noxious fumes.



“Energy storage applications, particularly at grid-scale, provide enormous market opportunities for companies with truly enabling solutions,” said Steve Vassallo of Foundation Capital. “We see Aquion’s novel energy storage technology as a game-changer in several key markets and are delighted to be part of their world-class team.”

“The Aquion team is committed to changing the way the world uses energy by delivering safe, reliable, and economical energy storage solutions,” said Scott Pearson, Aquion’s CEO. “We are very excited about our new investment partners and the assistance, both financial and operational, they can provide the company as we launch our first products and begin to scale the company globally”.

In the fall of 2011 Aquion will begin shipping its first pre-production energy storage systems to external testing facilities and selected strategic partners. In addition, Aquion is currently in the process of identifying and selecting an appropriate site for its first high volume factory in the United States. This manufacturing facility is expected to become operational in 2013 and create more than 500 jobs across a wide range of employment categories.

Coincident with this financing, Steve Vassallo of Foundation Capital and Bill Wiberg of ATV have joined the Aquion board of directors. Prior to this round, Aquion had been supported with funding from Kleiner Perkins Caufield & Byers and the U.S. Department of Energy.

ZBB to Provide Energy Storage for US Navy Micro-Grid Project

ZBB Energy Corporation (NYSE Amex: ZBB)was awarded a contract from the US Navy Fleet and Industrial Supply Center, San Diego (FISCSD). ZBB will provide a 1000kWH/500kW-rated energy storage system for use in a micro-grid application at the San Nicolas Island Naval Facility, located in the Catalina Island group just west of Los Angeles (see illustration). The system will utilize ZBB's newly branded EnerSystem technologies, comprised of ZBB's Power & Energy Control Center (PECC) and Version 3 zinc bromide flow battery modules.


The contract is for the supply of equipment and services for work supported by the Office of Naval Research-Technology Insertion Program for Savings (ONR-TIPS) with the purpose of accelerated transition of new technology. During the next two years, the EnerSystem will be tested and certified to maintain power quality and perform load management for off peak produced power of the wind turbines and diesel electric power plant power delivery system at NOLF-SNI. The certifying body is Idaho National Laboratories. This will be the first time that an advanced energy storage system is tested with large-scale renewable sources, in conjunction with actual load management and generator plant control schemes in a micro-grid application in North America. Successful tests and certification will make available transition of this technology to more wide spread Navy use.

The ZBB EnerSystem will be used continuously in an ongoing operational mode to minimize diesel gen set runtime in conjunction with wind turbines and future PV arrays on the island. The base's overall system will focus on the power control for micro-grid stability, quality, and load leveling needs on the base.

ZBB's power electronics (PECC) will be used to interconnect the flow battery modules and future renewable inputs to the existing base micro-grid and recently installed wind turbines. ZBB will work closely with the Navy in Port Hueneme, CA and the project's design and installation civilian contractor to define operational standards for advanced energy storage systems on micro-grids such as this project and for use at future naval facilities.

Gemasolar Touts 350 MWph/Day Power Plant with Energy Storage

From the first of May 2011, the commercial operation for Torresol Energy's Gemasolar power plant, the first commercial plant in the world to use molten salt storage in a central tower configuration with a heliostat field, yielded better results than were expected. With its 19.9 MW of power, Gemasolar reached peak production levels of over 350 MWh in 24 hours of uninterrupted operation.


Thanks to its storage capacity in July, Gemasolar was able to supply energy during the hours of highest demand in Spain: 12 pm and 10 pm. The highest demand in Spain has two peaks. One is produced in the day. The second one, in general the strongest, is produced just after sunset. The forecast for August is that Gemasolar will continue the upward trend it has maintained since its entry into operation last May.

Gemasolar, the world's first commercial high temperature solar plant, capable of reaching more than 500ºC degrees, to enter into commercial operation, boasts a storage capacity of 15 hours. That storage capacity makes it possible for it to supply energy to the grid based on demand, regardless of whether there is constant solar radiation. With this project, Torresol Energy has made generating dispatchable power from renewable energy sources a reality.

It is expected that Gemasolar will produce a net total of over 110,000 MWh per year by operating for a total of 6450 hours a year at full capacity. The summer months are when the plant is at its greatest efficiency; therefore, Torresol Energy's technicians estimate that come mid-September, its equivalent average production time will be 18 hours at full capacity per day.

The Gemasolar plant, located in Fuentes de Andalucía (Seville), is a property of Torresol Energy, a joint venture between the engineering and technology group SENER, and Masdar, Abu Dhabi’s multi-faceted renewable energy initiative. SENER has been responsible for supplying all of the technology for Gemasolar, the engineering detail design and for leading the EPC and commissioning works of the plant. As for Masdar, a strategic developer of renewable energy power projects, the company is proud of the commercial approach they have taken to funding and operating this facility.

Felicia Bellows, Executive Vice President of Development for Torresol Energy U.S.A., explains: "Currently we are the only company in the world that is commissioning a commercial central tower project with molten salt receiver capable of absorbing 90% of the solar radiation. Gemasolar is Torresol Energy's flagship project because of its innovative technology, and in the short term we expect to be able to develop similar plants on the South West Coast of the U.S., where there are optimal levels of solar irradiation."

Frank Wouters, the director of Masdar Power, said: “The first months of Gemasolar’s operation have exceeded expectations. Masdar Power believes in introducing and launching new technologies in the clean energy spectrum, and we will continue to explore fresh opportunities to implement such novel technologies that will bring multiple benefits to the community.”

Mercedes Sierra, Vice President of SENER office in the US, adds: "The efficiency of this technology, which is developed by SENER, is proving to be vastly superior to conventional solar technologies, either without storage systems or which can't reach such high temperatures."

Gemasolar can reach operating temperatures of over 500°C, much higher than plants with parabolic trough technology, as it does not require oil, but rather directly uses the salt as a transfer fluid. The salt, at over 500°C, generates hotter, pressurized steam to move the turbine, which significantly increases the plant's efficiency. Meanwhile, some of this hot salt is stored in order to continue generating electricity while there is no sunshine. Thus, Gemasolar, with a 19.9 MW turbine can supply electricity to a population of 25,000 inhabitants in the South of Spain.

Among the plant's most cutting-edge equipment is its receiver, located at the top of the tower over 130 m high, where the 2,650 heliostats of the solar field concentrate the solar irradiation at a ratio of 1000:1.

Purdue to Offer Energy Storage Program

Purdue University is developing a program in energy storage technology in cooperation with the Naval Surface Warfare Center (NSWC), Crane Division, located at Crane, Ind. Purdue and NSWC Crane expect the program eventually to lead to a master's degree in chemical engineering.

"This new program will train leaders in a technology that is becoming increasingly important in our modern world," said Victor Lechtenberg, interim associate vice president for engagement. "That the first students are from NSWC Crane means this training will be in the hands of people able to develop the technology quickly and for the benefit of our country."

"Expanding the academic education of our talented work force is sure to enhance their ability to better serve our warfighters," said Kyle Werner, division manager for energy, power and interconnect technology at NSWC Crane. "Energy and power requirements on the battlefield continue to grow at near exponential rates. With NSWC Crane as the Department of Defense's largest collection of resources dedicated to electrochemical power sources, developing next generation energy storage solutions is critically important to our mission."

The program began in July with two intensive segments for 16 students at the Crane West Gate Research Park. The summer program is non-credit but will offer a certificate. This fall, the students will take their first credit course.

The courses will be taught through a combination of on-campus and online delivery. They will come from chemical, materials and industrial engineering.

"Through a selection of courses and research/design projects, students will learn fundamentals of both engineering and energy storage technologies," said James Caruthers, Reilly Professor of Chemical Engineering and director of the program. "This program is a clear demonstration of how two of Indiana's leading institutions can partner on a project to increase technical capabilities in the state to address opportunities in energy storage of defense and industrial importance."

The master's in chemical engineering program is expected to take three years to complete. The initial program will be developed for NSWC Crane's specifications. Other individuals or businesses will be able to participate in future offerings.

This follows an agreement by Purdue and NSWC Crane in September of last year, focused on a broad range of projects designed to provide state-of-the-art energy storage and power management technologies for U.S. combat forces. Among the planned research areas are battery efficiency and safety; high-fidelity sensors for energy storage systems; mitigation of lithium battery fires; hydrogen storage research; bio material growth, harvesting and processing for power; and fuel cell advancements.

DoE Awards Nearly $7 Million to Advance Fuel Cell and Hydrogen Storage Research

The U.S. Department of Energy announced nearly $7 million over five years for independent cost analyses that will support research and development efforts for fuel cells and hydrogen storage systems. The four projects – in California, Ohio, and Virginia – will generate rigorous cost estimates for manufacturing equipment, labor, energy, raw materials, and various components that will help identify ways to drive down production costs of transportation fuel cell systems, stationary fuel cell systems, and hydrogen storage systems. These projects will provide important data that will help the Department focus future research and development funding on the fuel cell components and manufacturing processes that can deliver the greatest gains in efficiency.

"These projects will help advance our fuel cell and hydrogen storage research efforts and bring down the costs of producing and manufacturing next generation fuel cells," said U.S. Energy Secretary Steven Chu. "These technologies are part of a broad portfolio that will create new American jobs, reduce carbon pollution, and increase our competitiveness in today's global clean energy economy."

The DoE said these projects will generate lifecycle cost analyses of existing and conceptual fuel cell systems for transportation and stationary applications. The projects will analyze a range of system sizes, manufacturing volumes, and applications, including transportation, backup power and material-handling equipment such as forklifts. Cost analyses are conducted by designing the system and conceptualizing its manufacturing process, selecting manufacturing equipment, determining labor and energy, and obtaining prices for materials and manufacturing equipment. The design of systems and manufacturing process is guided and vetted through system models at National Laboratories, patent and literature research, presentation from developers, and peer review.

The four projects selected for award are:

• Directed Technologies, Inc. – Arlington, VA – up to $3 million for two projects
  Directed Technologies will conduct two cost analyses under these awards – one focused on transportation fuel cell systems and the other on hydrogen storage systems. The transportation fuel cell systems project will analyze and estimate the cost of transportation fuel cell systems for use in vehicles including light-duty vehicles and buses. The cost analyses of hydrogen storage systems will also examine various cost parameters including capital equipment, raw materials, labor, and energy to gain an understanding of system cost drivers and future pathways to lower system costs. The analyses will include rigorous annual cost estimates of fuel cell power systems or hydrogen storage systems that will help industry optimize the design of components and manufacturing processes at various rates of production. Sensitivity studies will examine how total manufacturing costs are affected by changes to the fuel cell system design and cost parameters such as platinum price, cell power density, operating pressure, operating temperature or the number of cells in the fuel cell stack.
  
• Lawrence Berkeley National Laboratory – Berkeley, CA – up to $1.9 million
  Lawrence Berkeley National Laboratory will develop total cost models for low- and high-temperature stationary fuel cell systems up to 250 kilowatts (kW). This project will yield accurate projections of current system costs and assess the impacts of state-of-the-art manufacturing technologies, increases in production volume, and design changes on system and lifecycle costs for several near-term and emerging fuel cell markets.
  
• Battelle Memorial Institute – Columbus, OH – up to $2 million
  Over the course of this project, Battelle Memorial Institute will provide cost assessments for stationary fuel cell applications up to 25 kW, including forklifts, backup power units, primary power, and combined heat and power systems. The project will also provide cost analyses of large-scale fuel cell applications ranging from 100 to 250 kW, such as auxiliary power, primary power, and large-scale combined heat and power systems. The analyses conducted under this project will provide a better understanding of performance, design and manufacturing options, and life-cycle costs, which will help optimize fuel cell designs, manufacturing methods, and target applications.