Energy Storage Gets Exponentially Cheaper Too

Rameez Naam has a post on the exponential decrease in energy storage costs - Energy Storage Gets Exponentially Cheaper Too.

A back-of-envelope says we need to bring the cost of energy storage down by another factor of 10 in order to make grid-scale storage cheap enough to displace most fossil use for electricity. On current trend, it looks like well be there in the next 15-20 years.

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The battery storage system that could close down coal power

ReNew Economy has an article on a German energy storage technology company - The battery storage system that could close down coal power.

You don’t have to go far inside the headquarters of German battery storage company Younicos, or even their website for that matter, to find out what they are about. “Let the fossils rest in peace,” the logo suggests. Another sign at their technology centre east of Berlin proclaims: “You are now leaving the CO2 producing sector of the world.”

This sign is designed to mimic those which adorned the checkpoints that separated the various sectors of east and west Berlin before the wall was torn down. Younicos believe they have a technology that is equally disruptive, and can break down one of the last barriers to 100 per cent renewable energy: the need to run fossil fuel generation to control the “frequency” of the grid, and the other system services such as voltage control.

The company, based in Berlin Adlershof, on the eastern outskirts of the capital, is developing 10MW-sized battery parks, using battery systems that it says can stabilise the grid faster, cheaper and with greater precision that conventional generation.

It says that these systems can substitute 10 times the capacity from conventional generation – coal, nuclear and gas – and at a fraction of the cost. According to Younicos spokesman Philip Hiersemenzel, each battery park can be installed at around € 15 million, which means that for an investment of €3 billion, conventional generation in Germany’s 80GW would no longer be needed – at least for frequency and stability purposes.

This is critical is Germany. The sheer scale of their solar PV installations – it has more than 35GW – means that on some days it already produces more than half the country’s electricity needs. But baseload generators have to keep running for the sake of frequency control and system stability, this has caused spot prices to plunge well below zero.

For an 80GW grid, it needs about 20GW and 25GW of “must run” balancing to maintain frequency and keep the grid stable. Younicos says 2GW of its battery parks would render this need redundant. Around 200 of it battery parks could be installed around the country at a total cost of around €3 billion.

(Of course, that is not the only impediment to 100 per cent renewables – enough solar and wind power needs to be built, and other storage is needed, battery storage to respond to variations in load on a minute by minute and hour by hour basis, and longer-term or “seasonal” storage, which can take excess production and store it – synthetic diesel, hydrogen etc.).

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Large Capacity Lithium Ion Storage Units

After Gutenberg has a post on a Japanese energy storage / frequency control unit using Lithium Ion batteries - Large Capacity Lithium Ion Storage Units.

This blog reported before about energy storage that absorbs or delivers energy to the grid at intervals of five seconds. The frequency regulation system uses thousands of lithium-ion batteries.”

Now Green Car Congress reports on “Japan’s first cargo container-type large-capacity energy storage system using Li-ion batteries.” Mitsubishi Heavy Industries, Ltd. has developed a system capable of providing power of up to one megawatt (MW)

Its mobility makes the system suitable for a wide range of applications, including emergency use. The actual system has been installed at the Nagasaki Shipyard & Machinery Works of MHI in Nagasaki Prefecture, Japan, to begin verification testing for a power stabilization system application from early July towards the commercialization of the system.

The container-type “megawatt-class large-capacity energy storage system (ESS)” consists of a 40ft-long container unit, which houses more than 2,000 units of lithium-ion rechargeable batteries, and a 20ft-long container unit, in which two power conditioners are installed. Power conditioners are used for direct current (DC)/alternating current (AC) conversion and their input/output control. Each container unit can be moved by container trailers. The system has a capacity of 408 kWh and is designed to have a system efficiency of 90%.

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Battery Storage Could Get a Huge Boost from Seaweed

Technology Review has an article on a possible technique for greatly improving the performance of lithium-ion batteries - Battery Storage Could Get a Huge Boost from Seaweed

Lithium-ion batteries could hold up to 10 times as much energy per cell if silicon anodes were used instead of graphite ones. But manufacturers dont use silicon because such anodes degrade quickly as the battery is charged and discharged.

Researchers at the Georgia Institute of Technology and Clemson University think they might have found the ingredient that will make silicon anodes work—a common binding agent and food additive derived from algae and used in many household products. They say this material could not only make lithium-ion batteries more efficient, but also cleaner and cheaper to manufacture.
Lithium-ion batteries store energy by accumulating ions at the anode; during use, these ions migrate, via an electrolyte, to the cathode. The anodes are typically made by mixing an electroactive graphite powder with a polymer binder—typically polyvinylidene fluoride (PVDF)—dissolved in a solvent called NMP. The resulting slurry is spread on the metal foil used to collect electrical current, and dried.

If silicon particles are used as the basis of the electroactive powder, the batterys anode can hold more ions. But silicon particles swell as the battery is charged, increasing in volume up to four times their original size. This swelling causes cracks in the PVDF binder, damaging the anode. In research published today by Science, the Georgia Tech and Clemson scientists show that when alginate is used instead of PVDF, the anode can swell and the binder wont crack. This allows researchers to create a stable silicon anode that has, so far, been demonstrated to have eight times the capacity of the best graphite-based

The polymer alginate is made from brown algae, including the type which forms forests of giant kelp. It is already widely used as a gelling agent and a food additive. Initially, the researchers thought to replace PVDF with a combination of several different materials. Then, on theoretical grounds, they realized that a polymer with just the right kind of uniform structure could do all the things the binder was supposed to do, including providing good structural support while not chemically reacting with the electrolyte.

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Final Tests For Torresol’s CSP Plant With Molten Salt Storage Complete

The National reports that Torresol’s solar thermal power plant in Spain has completed testing - Spanish solar plant built by Masdar is well worth its salt. The plant includes 15 hours of storage, making it able to operate around the clock for much of the year.

A Spanish solar plant built by an Abu Dhabi company is set to power homes even during the night. Masdar, which is owned by Mubadala Development, and a Spanish joint venture partner have completed the final tests on a solar plant in Seville, in southern Spain. …

Thousands of mirrors at the plant concentrate the suns energy on a single tower holding molten salt, which developers believe is so effective at retaining heat that it will be able to produce power 24 hours a day from March to October. "Were basically decoupling the solar [input] from the electricity generation," said Frank Wouters, the director of Masdar Power.

The tower is the first part of Masdars €1 billion (Dh5.18bn) investment in Spanish power production. That includes two 50 megawatt solar parks being built by Torresol Energy, Masdars 40-60 joint venture with the Spanish engineering company Sener.

Bloomberg has a look at Masdar’s overall plans for clean energy - Abu Dhabi’s Masdar Has $5 Billion in Solar, Wind Power Projects.

In Spain, the company has three solar projects worth about $1 billion, Wouters said at a media briefing in Abu Dhabi today. A 20-megawatt plant will start producing power this month and two 50-megawatt facilities will start this year, he said. Masdar also has stakes in the 1-gigawatt London Array offshore windfarm and a 6-megawatt offshore wind project in the Seychelles.

Abu Dhabi, which holds almost all the oil reserves in the United Arab Emirates, is investing in solar and wind power all over the world to pioneer the use of renewable energy. The emirate is building Masdar City, a business and residential complex designed to minimize carbon emissions, and serves as headquarters for the International Renewable Energy Agency.

Masdar is a key component of Abu Dhabi’s aim to generate at least 7 percent of the power it uses from renewable sources by 2020. Growth in power demand to more than 20,000 megawatts by the end of the decade would require about 1,500 megawatts from projects such as wind and solar plants, according to data from Abu Dhabi’s utility.

The company’s domestic projects include the Shams 1 project, the largest concentrated solar plant in the Middle East, which is 45 percent complete and will be ready next year, according to a statement received by e-mail today. Masdar expects to award a construction contract for the 100-megawatt Noor 1 photovoltaic plant by the end of 2011 and may start building a 30-megawatt wind farm on Sir Bani Yas island

Renewable Energy World has a detailed look at the technology being used in the Spanish solar thermal plants - CSP: Targeting Grid-Parity in Spain

Concentrated solar power (CSP) uses mirrors to concentrate sunlight and generate heat and is typically used to generate electricity via a conventional steam cycle.
Unlike photovoltaic farms or wind energy — which has grown to become Spains third largest power source — CSP plants can cost-effectively store energy that cannot immediately be used. In Spain, which has a second demand peak in the evening, this is important. Most new CSP projects incorporate storage so they can keep generating electricity several hours after the sun has gone down, or even right through the night.

But, while CSP is more dispatchable than other renewable energy sources, it also currently costs more. So Spain is the focus for efforts to drive down costs, both through economies of scale and improvements in technologies.

All the CSP technologies are expensive so a lot of research seeks to reduce component costs and optimise production and installation, says Eduardo Zarza, head of R&D for solar concentrating systems at the Plataforma Solar de Almería (PSA), Spains leading solar energy research centre, which researches all four types of CSP technologies. The most mature CSP technology is the parabolic trough design, which accounts for 93% of the 2500 MW of new CSP capacity that Spain has authorised up to 2013. While the other three technologies — solar tower, Fresnel collector and Stirling dish — all have commercial potential, the financial backers of Spains CSP projects have opted to reduce their risks through parabolic troughs longer track record. In the US, parabolic-trough plants date back to the 1980s.

With a tower system, for example, it is difficult to get project finance because no one knows how long the receiver will last, says Frank Dinter, head of solar at RWE, the German utility, which is investing in several Spanish renewable projects.

To benefit from Spains generous feed-in CSP tariff — currently 28 euro cents/kWh for 25 years — CSP plants cannot exceed 50 MW. This size limit is seen as less than optimal, given the current maturity of parabolic-trough technology, and limits potential benefits from economies of scale. Several costs in a CSP project are not proportional to its size. For example, a 200 MW turbine costs less than four times as much as a 50 MW turbine. Dinter estimates that a 200 MW plant would be about 25% cheaper per megawatt than a 50 MW plant. ...

The best places to locate CSP plants tend to be arid regions with little cloud, but such environments are often subject to water restrictions. A plant such as Andasol 3 consumes 500,000 m² of water a year, mostly to condense steam, but also to clean mirrors.Investors in Novatec Solars PE2 plant insisted on air cooling to avoid such controversy, even though reduces the economic return.

Air cooling costs much more and it reduces the output by 5%-6%, says Selig. Opinions are nevertheless divided on this issue. RWEs Dinter says water cooling is essential to boost the thermodynamic efficiency of the steam cycle of parabolic-trough plants like Andasol 3 with a relatively low inlet temperature. With dry cooling, you cannot reduce the outlet temperature as much as with water, he says.

Burgaleta of Torresol Energy says that even though the Gemasolar central tower plant works at higher temperatures, water access was not a problem, and so the designers opted for water cooling. But one of Torresols central tower projects planned for the future will have air cooling instead, he adds.

As Spain is now discovering, concentrating solar power is far from being a single technology, but rather embraces a wide range of designs and key technologies, each with different operating characteristics, risk profiles and trade-offs. There is no clear winner, clarifies Siemens Mürau.
Even without any radical technological breakthroughs, improvements in technologies and greater economies of scale are expected to drive a 30% reduction in the cost of CSP-generated electricity in Spain by 2015. And by 2025, costs may fall as much as 50%, at which point CSP plants will finally be in a position to substitute conventional sources in Spains energy mix.

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