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German researchers hit record high PV cell efficiency

A new photovoltaic cell structure has reached a record efficiency after three years of research at Germany’s Fraunhofer Institute for Solar Energy Systems.

[T]he German Fraunhofer Institute for Solar Energy Systems have created a solar cell that’s 44.7 percent efficient, meaning it converts 44.7 percent  of the sun’s energy into electricity. The new record isn’t much higher than the previous record of 44 percent , set in December 2012, but as TreeHugger notes , it brings the solar industry closer to achieving 50 percent efficiency.

The panel is constructed out of a new solar cell structure, using subcells to raise the overall efficiency of the panel.

These cells are used in concentrator photovoltaics (CPV) a technology which, according to , “achieves more than twice the efficiency of conventional PV power plants in sun-rich locations.”

Solar cells based on this new design are not currently available and it may take several years to reach a point where they can be mass produced. However, this is leading the industry in a direction of even lower costs for solar power and higher efficiencies than we’ve seen.

To read more about the new solar cell design, visit



Battery storage installations increase as battery tech. advances

With the proliferation of solar panels and other renewable energy production technologies increasing the amount of power being pushed onto the power grid, there is a need for some sort of dampening to keep the aging grid from being overwhelmed. Battery storage is one of the major solutions to this problem, however the technology behind these storage systems has not been able to keep up with needs. Recently, utilities have been testing large scale battery storage systems.

NSW network operator Ausgrid is installing a 60kW battery storage system in the Sydney suburb of Newington to see how it can help manage summer peak demand events.

The installation of the lithium-ion storage system is the biggest battery trial so far for Augrid, which operates in the eastern half of Sydney, the central coast and the Hunter region.

“Managing peak summer demand is our key driver as network operator. If we can knock that on the head, that’s a big saving for us,” he told RenewEconomy.

The full results of the suburban battery storage program, which used batteries from Australian developer RedFlow about the size of a small fridge, have not been released.

But Myors said the program showed that the technology was reliable and customer acceptance was good.   One of the key challenges was making sure that the storage was able to dispatch for the entire peak period. “Peak lasts for a certain number of hours. You don’t want battery to run out of puff, because you will lose the benefit for the network.

Ohio is also host to a new battery storage system, being tested by AES Corp.:

AES’ Dayton Power & Light utility will use the storage at its Tait generating station in Moraine, Ohio, to stabilize an electric grid that supplies electricity to more than 60 million people, the company said today in a statement.

The facility is Ohio’s largest electric-storage system, with 800,000 cells, and adds to 60 megawatts of battery capacity the Arlington, Virginia-based company operates in the region.

If this trend continues, battery storage could become a regular part of the power grid, rather than functioning as a solution to a problem.



California builds up solar capacity in Mojave Desert

In the Mojave Desert there is an array of 170,000 mirrors called heliostats. This project, based on solar thermal energy, will be another big step in the state of California reaching its goal of one third of its energy from renewable sources by 2020.

"The total project will power 140,000 California homes, so one way to look at it is one heliostat powers one home," says Tom Doyle, the CEO of NRG, the company heading this massive solar project.

"In fact, this is the largest concentrated solar thermal project in the world," Doyle said.

Doyle says the project is displacing 400,000 tons per year of C02 by using solar energy in lieu of fossil fuel capacity.

The project is funded privately, though it is backed by a federal loan guarantee to the tune of $1.6 billion and they are leasing land from the federal government.'s not cheap - this project cost $2.2 billion. It's privately funded by several companies including Google, which invested $168 million. The project is backed by a $1.6 billion federal loan guarantee and they lease the land from the government.

The hope for this project is that it will be usable in many other desert locale, including the American Southwest and the Middle East.

Read more about the heliostat project at CBS News.



California to offer incentives for buying battery storage

A large number of early adopters of solar power were disappointed to find out that if their panels were tied into the grid, they would not automatically have power if the grid went down. Now, battery storage is more accessible than ever and able to provide power when the grid goes down. The state of California even has an incentive for solar PV users to add storage to their systems.

The California Self-Generation Incentive Program (SGIP) has been brought back and is now including Advanced Energy Storage (aka battery backup). So, what does that mean for Californians? This is a big step towards energy independence, even for the grid-tied utility customer. How can we go from 30-40% clean energy all the way to +70% here in California? The answer is a more flexible grid. And energy storage is part of the solution that provides us with that flexibility.

With the revived program, homeowners or business owners who have already gone solar or are now installing a solar system can invest in energy storage and store their generated electricity for use later and avoid using the energy generated from their solar systems during peak times. It’s the old adage “buy low, sell high.”

Now customers of PG&E, SCE, and SDG&E can save $1.80/W for energy storage, plus an additional 20% of the incentive when installing products from a California supplier. There are of course limitations and exclusions of this program – customers must be grid-tied to one of the eligible utilities, must use new equipment installed by a California-licensed contractor, and cannot be connected to a non-renewable generator, such as a standard diesel generator. But for that, they are only required to pay a minimum of 40% of the project cost!

This renewal of incentives in California will help the state reach its renewable energy goals as well as reduce emissions and peak demand. If the promise of an incentive wasn’t enough to add storage to your solar PV system, the knowledge that it will will pay to add storage early just might be, since the incentive will decrease 10% each year.

Read more about California’s power storage incentive at Clean Technica.



Molten air could increase capacity, reduce weight in battery technology

With energy storage becoming increasingly important for the adoption of renewable energy sources, creating more efficient, longer lasting, and higher capacity batteries than we currently have is taking precedence. A team led by George Washington University Chemist Stuart Licht is doing just that.

A new class of rechargeable batteries – 'molten air' batteries – solve these challenges by using highly conductive molten electrolytes and very high capacity multiple electron compounds such as carbon and vanadium diboride (VB2). Unlike prior rechargeable molten batteries, the molten air battery is not burdened by the weight of the active chargeable cathode material. The rechargeable molten air electrode instead uses oxygen directly from the air to yield high battery capacity.

"Molten air batteries advance the field of energy storage by opening up multiple opportunities for new higher capacity batteries," Stuart Licht , a professor of chemistry at George Washington University, tells Nanowerk. "These are the first batteries to reversibly use oxygen from the air to store energy via a molten salt and multiple electrons stored per molecule at the counter electrode."

While still experimental, the technique they are using, which is explained in the paper they published in an online edition of Energy & Environmental Science, is a proof of concept could lead to many different applications, both large and small scale.

Potential applications of these molten air batteries could be large scale energy storage for electric grids (for example to store electricity when wind or solar electric is not available); higher storage capacity for electric cars (for example this system has much greater capacity than high temperature sodium sulfur batteries which had been previously investigated); or higher storage capacity for drones.

To read more, visit



SwRI testing electric vehicle energy storage

The Southwest Research Institute (SwRI) recently began testing an electric vehicle aggregation system that uses a new Society of Automotive Engineers (SAE) standard for bidirectional power. This new SAE standard is based on Direct Current for faster charging.

The system, part of the Smart Power Infrastructure Demonstration for Energy Reliability and Security (SPIDERS) Phase II program, is controlling five DC fast-charge stations at the Fort Carson Army Base in Colorado Springs, Colo. In August, the system passed integration and acceptance testing, successfully aggregating electric vehicles from two vehicle manufacturers equipped with SAE-compliant bidirectional charging interfaces.

The bidirectional, aggregation system allows for energy to flow from the electric vehicles where it is being stored and into the grid to help the power grid when the base’s needs increase.

“SPIDERS is pioneering a new way of managing energy,” said Yaxi Liu, a research analyst also in the Automation and Data Systems Division. “The batteries in electric vehicles are used as cushions against fluctuations in the grid, creating more stability and resiliency while improving its ability to accommodate renewable energy. This helps satisfy goals of reducing dependence on fossil fuels and the impact of emissions.”

Moving beyond this test, if the use of electric vehicles as part of the larger grid system catches on, peak demands on the greater power grid could be reduced, helping reduce overall carbon emissions from the power grid.

Read more on the new SwRI project at



50 megawatt pumped hydro project approved in Wales

A new pumped hydro power project is planned for the Gwynedd region of Wales that will add to the 1,728 megawatt power station already in place.

On Monday, the Gywnedd Council planning comission granted developer Quarry Battery planning permission to develop the Glyn Rhonwy site, on the on the edge of Snowdonia National Park. The company says the £100 million ($156 million) project, capable of storing up to 600 megawatt-hours of energy, could be operational by 2017.

“By putting small-scale storage near to centres of energy generation such as wind farms, and others near centers of heavy consumption such as major cities, we will cut down on distribution losses and network transmission costs, making whole regions of the U.K. increasingly self-sufficient in renewable electricity,” Quarry Battery managing director Dave Holmes said, according to a BBC report .

The project would repurpose two quarries at different elevations to act as reservoirs that are conveniently near grid connections, making this an ideal location. And with pumped hydro being a reliable way to add stability and storage capacity to the power grid, the biggest hurdle to cross now is to get this project started without destroying the aesthetic of the Snowdonia landscape.

Read more about pumped hydro at Earth Techling.



Investment in power storage tested at Borrego Springs site

SDG&E has been testing current energy storage technology in conjunction with a microgrid used to power the town of Borrego Springs in California.

For the area’s 3,400 residents, the charged batteries can meet roughly one-tenth of energy needs.

That represents a significant technical advance that might some day lower peak power demands that drive electricity prices higher and stoke the need for major power lines and power plants.

SDG&E’s test could be a look at what might become the norm in California after the October vote on a mandate requiring investor-owned utilities to add 1.3 gigawatts of energy storage capacity by 2020.

The proposed mandate, coming to a final vote as soon as Oct. 3, is akin to bottling the output of a large nuclear reactor.

The goal is to create a cost-effective market for energy storage that supports multiple technologies.

Approval would accelerate investment and development in a host of storage technologies, from flow batteries with nearly unlimited longevity to compressed-air storage that pressurizes underground caverns to later spin electrical turbines.

California’s goal is to implement technologies that can be deployed anywhere in order to improve the power grid’s stability. However, it is the utility customers that will be paying for these changes and improvements.

Utility customers, including SDG&E customers in San Diego and southern Orange counties, would pick up the tab, with rough estimates running as high as $3 billion for meeting the 2020 targets.

New storage capacity would be added gradually at first, raising the stakes incrementally as policy makers and the industry learn from experience.

“The proposal is designed to be aggressive but realistic,” wrote Public Utilities Commissioner Carla Peterman, the author of the plan.

By adding storage capabilities to the power grid incrementally, the investment from consumers can be minimal, while being able to store more and more energy and stabilizing the power grid.

Read more on California’s move to power storage at UT San Diego.



Tech firms ramping up transmission technology research

Recently companies like General Electric, Toshiba, and ABB have announced projects concerning new power transmission technologies, including high-voltage Direct Current transmission in response to the forecasted increase in electricity demands.

Simply put, the world is going to need more transmission capabilities. The Energy Information Administration estimates that electricity demand will grow 93 percent over the next 27 years, rising from 20.2 trillion kilowatt hours in 2010 to 39 trillion kilowatt hours by 2040. Most of the growth will occur in emerging nations, where transmission and distribution networks are often inadequate, rickety and subject to failure.

These technologies are not being developed in response to microgrid systems that are becoming more popular, they are being developed to be used in addition to microgrid systems, since there will be a need for long distance transmission.

While decentralized power delivered through microgrids and energy storage will likely play a fundamental role in meeting the demand for electricity in these countries, it’s a good bet that centralized power plants linking to long-distance transmission lines will be there too. You can’t live next door to an offshore wind farm, after all. In China, the areas of high solar radiation are located far away from manufacturing and urban centers, according to Frank Haugwitz, director of the Asia Europe Clean Energy Advisory Co.

These technologies will be better able to handle the influx of renewable energies as well as be more efficient.

The latest technology, meanwhile, provides distinct advantages. An HVDC transmission line carrying thousands of megawatts might lose 6 to 8 percent of its power over 1,000 miles. A similar AC line can lose 12 to 25 percent. DC lines can also better manage the variable output from renewable power plants. South Korea, China, Japan and the Scandinavian nations were early adopters of HVDC: the U.S. has projects underway as well.

Read more about the new transmission technology at



New Jersey to test new power grid technologies

US Energy Secretary Ernest Moniz announced a study on ways to make the power grid more resilient during storms and other natural disasters while visiting New Jersey recently.

Standing in the Secaucus Junction train station with Gov. Chris Christie, they announced a partnership to design a new electrical microgrid — the first non-military microgrid of its kind — to keep commuters moving if the larger electrical grid fails.

The Department of Energy has pledged $1 million to the study.

Hurricane Sandy caused widespread outages to New Jersey’s electric grid, leaving about two-thirds of the state without power.

In the aftermath of the devastating storm, Hurricane Sandy, there is a great learning opportunity and a push to find a better solution for the resiliency of the power grid.

Read more about New Jersey’s power grid test here.



US Navy to test connecting microgrids

At three bases in the San Diego, California region, the US Navy is testing their microgrid technologies by connecting them together. This is being undertaken as a way to improve energy supply security and reduce energy consumption.

Kevin Meagher, Power Analytics president and CTO, said in an interview last week that the three microgrids, at the hospital at Naval Base San Diego, a data center at Naval Base Coronado and at Naval Base Point Loma, are now equipped with the on-site generation, solar power, energy storage and grid controls they need.

“The circuits are there; for the most part, all of the hardware is there,” Meagher said. “The trick to doing this is to take the existing circuits, the existing equipment, and figure out how to make it all work to meet the requirements” of the project, which are to provide the “first comprehensive, real-time view of the status of its critical power systems across multiple bases.”

Meagher broke down the project’s imperatives into three broad categories. First, “it clearly presents the opportunity for a cluster of microgrids from an economic perspective,” to do things like “wheel” power from base to base, or to optimize the way the combination of microgrids draws from the grid at certain times, versus relying on their own generation and energy storage capabilities.

Second, "Because of the synchronization of the data, it allows you to talk about enhancing or modifying the structure, either to enhance stability at a specific microgrid, or not, depending on what happens on each of the bases,” he said. In other words, it’s a way to study not just what the cluster can do as presently configured, but how it can be changed to maximize that potential.

“The third thing is the same thing that everyone talks about, but it’s still very near and dear to the Department of Defense -- that’s situational awareness,” he said. In other words, this microgrid cluster is meant to be an “early warning system,” to allow the Navy to predict and prepare for power disruptions, whether they stem from the grid they’re connected to, or from internal changes like routine maintenance of various systems.

The microgrids being used by the Navy, and the rest of the military, are considered a stepping stone for private-sector microgrid adoption and part of a greater standardization of microgrid components. The information gained through these applications will pave the way toward the mass implementation of microgrid systems.

Read more at Green Tech Media.



Water and salt-based battery could change the energy storage game

After testing various materials, researchers at Murdoch University, in Perth, Australia, have developed a new battery with potential to offer cheap and reliable energy storage using water and sodium ions.

“To provide power at non-generation times, excess energy needs to be stored in batteries, but storage technologies now being considered, such as molten salt or molten sulfur, work at high temperatures, making them expensive and impractical,” said Senior research fellow and project leader Dr Manickam Minakshi. “Our water-based sodium-ion battery has shown excellent potential for affordable, low-temperature storage.”

The team from Murdoch’s School of Chemical and Mathematical Sciences tested various metals and phosphates to produce a cost-effective battery with high energy density made from manganese dioxide and a novel olivine sodium phosphate.

Dr Minakshi says sodium appealed as a key ingredient because, while its chemical properties are similar to lithium, it’s a good deal cheaper and far more abundantly available. The main challenge it presented, he says, was to find material for cathodes and anodes capable of accommodating sodium’s ionic size, which is  2.5 times larger than that of lithium.

“Ions travel out of the cathode and into the anode to form a current. As an imperfect analogy, you can think of them as mesh filters that ions pass through. We had to find materials with larger gaps in their mesh,” Dr Minakshi said. The team eventually found success with manganese dioxide as the cathode, and a olivine sodium phosphate as the anode.

The resulting battery, says Dr Minakshi, is a safe, cost-effective battery with high energy density, with “excellent potential for large-scale use, including storing energy from wind turbines and solar farms for later feeding into local electricity grids, as well as use in industry.”

The battery technology developed by the Murdoch University team isn’t the only water-based battery to be developed. Another water-based battery was developed by Aquion Energy, a company started out of Carnegie Mellon University. Their battery is set to made available for commercial sale in 2013.

As Technology Review has since reported this February , Aquion Energy has this year selected a site for its first (reportedly fully funded) factory – “a sprawling former Sony television factory near Pittsburgh” – and says production capacity will be “hundreds” of megawatt-hours of batteries per year. The company says it initially hopes to make batteries for under $300 per kilowatt-hour, which can be recharged 5,000 times and could last for over a decade in situations in which they’re charged once a day.

The difference between the two water-based batteries is the phosphate-based anode in the Murdoch University version. Their batter also is still in early stages of testing, but can last 12 hours under average current rates. The Murdoch University team is hoping to move toward commercialization as a low-cost source of power.

Read more about the water-based battery technology at RenewEconomy.