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Prescott Valley to Flip the Switch on Solar Power Facility

Just five months after breaking ground, the Town of Prescott Valley, Arizona, along with several project partners, is now celebrating the completion of two major solar projects that have been designed to serve them solar energy for many years to come.

Town officials and participating builders and investors will be on hand for a ribbon cutting ceremony Tuesday, May 1, at 2:00 P.M.  They will officially flip the switch, providing the Town with an affordable, long-term energy source. The event will be held at the Tank Farm solar facility located at 3820 N. Prescott East Hwy, Prescott Valley, AZ.

The installation was facilitated in part by the Arizona Public Service Renewable Energy Incentive Program. This program offers financial incentives to customers who add renewable energy systems to their homes or business. It is funded by APS customers and approved by the Arizona Corporation Commission.

Smart Energy Capital, a leading solar development and finance company, partnered with INDU Solar Holdings, LLC (“INDU Solar”) and Wilson Electric of Tempe, Arizona, to build the approximately 1.5-megawatt DC ground-mount fixed tilt systems. The 13,524 solar modules, housed at the town’s water pump stations and wastewater treatment plant, will provide a significant amount of solar-generated power over the life of the projects.

“We are excited to celebrate the completion of the development and construction phase of Prescott Valley’s large solar energy projects and look forward to continuing to support solar development in Arizona,” said Smart Energy Capital Managing Partner Brian Weisman. Smart Energy funded the development phase of the projects and a project company owned by INDU Solar funded the installation.  Under the terms of a 25-year power purchase agreement, the project company owned by INDU Solar will sell 100 percent of the electricity that the facility generates to the town of Prescott Valley at a fixed rate.

About INDU Solar Holdings, LLC
INDU Solar is a joint venture formed by Integrys Solar, LLC, a wholly-owned subsidiary of Integrys Energy Services, Inc., and Duke Energy Renewables, a wholly-owned subsidiary of Duke Energy Corp., to develop, construct, finance, own and operate solar photovoltaic projects that are originated and developed on behalf of commercial, school, government and utility customers throughout the United States. The joint venture, developed in partnership with Smart Energy Capital, is unique in that it provides 100 percent of the financing for project construction and incorporates all federal tax benefits in a single structure, thereby eliminating the need for separate construction financing or tax equity structures for individual projects.

About Duke Energy Renewables
Duke Energy Renewables, part of Duke Energy’s Commercial Businesses, is a leader in developing innovative wind and solar energy solutions for customers throughout the United States. The company’s growing portfolio of commercial renewable assets includes 10 wind farms and 11 solar farms in operation in eight states, totaling approximately 1,000 megawatts in electric-generating capacity. Learn more at www.duke-energy.com/renewables. Headquartered in Charlotte, N.C., Duke Energy is a Fortune 500 company traded on the New York Stock Exchange under the symbol DUK. More information about the company is available on the Internet at: www.duke-energy.com.

About Integrys Energy Services, Inc.
Established in 1994, Integrys Energy Services, Inc. provides competitive energy supply solutions, structured products, and strategies that allow retail residential, commercial, and industrial customers to manage their energy needs. Its principal energy marketing operations are in the northeastern quadrant of the United States. Through its subsidiary, Integrys Energy Services – Natural Gas LLC, Integrys offers natural gas products to a full range of end-users throughout the Midwest. Areas of generation expertise include cogeneration, distributed generation, renewables such as solar and landfill gas, as well as clean fuel generation, with facilities in selected markets throughout the United States. More information about Integrys Energy Services is available online at www.integrysenergy.com. Integrys Energy Services is a subsidiary of Integrys Energy Group (NYSE: TEG), a Fortune® 500 company with a 150-year heritage. More information about Integrys Energy Group, Inc. is available online at www.integrysgroup.com.”

About Smart Energy Capital
Smart Energy Capital, LLC (www.smartenergycapital.com) is a leader in the financing and development of solar energy projects for commercial, government, and utility customers.  The Company manages the development, financing, installation, and operations of distributed power plants throughout the United States. The company maintains extensive relationships with an array of lenders and investors.

3-D design from MIT team increases solar panel efficiency

Innovative 3-D design from an MIT team can more than double the solar power generated from solar panels in a given area. For more info see MIT News Release.

The Future of Solar Energy Technology

Current solar energy technology employs photovoltaic (PV) cells to generate electrical power by converting solar radiation into electricity. The cells are made from semiconductor-grade crystalline-silicon wafers, which are then packaged and assembled into solar panels.

Silicon is a natural element however high-grade silicon is expensive to produce. It is also in such high demand from the computer chip industry that prices have soared in recent years.

For solar energy to enjoy world-wide acceptance as an energy resource, the cost to produce it must fall in line with competitive resources such as coal and natural gas. In that regard the solar energy industry is constantly searching for new materials that are more efficient and cheaper to produce than silicon.

Other technologies that are being explored for the future of solar power include the following:

1) Thin Film Solar Cells (TFSC)
Though not as efficient as conventional PV cells, thin film solar cells use about 99% less silicon in their construction, which makes them more affordable to produce. TFSCs also use alternative photovoltaic materials such as Cadmium Telluride (CdTe) and Copper Indium Gallium Selenide (CIGS). CIGS currently holds the record for thin-film solar efficiency at 17.4%.

A new material for TFSC is Dye-Sensitized Solar Cells (DSSC) also knows as a Grätzel cell, named after its inventor, Michael Grätzel. DSSCs are notable for their low cost material, low cost processing and that they can be manufactured into flexible sheets.

2) Colloidal Quantum Dots (CQD)
CQD is an emerging field in solar cell research. Colloidal refers to elements in liquid suspension. Quantum dots are nanoparticles of semiconductor material.
Because of their small size CQDs can be painted or sprayed onto flexible surfaces such as plastic. They are less expensive to produce and more durable than silicon-based cells.

3) Chlorosomes
Chlorosomes are antenna-like structures found in the living cells of green sulfur bacteria. They are among the most efficient light-harvesting antenna complexes found in nature. Their ability to capture light in very low-light situations have researchers on a path of developing photosynthetic proteins for use in biologically inspired solar cells. These bio-inspired solar cells promote the idea of making solar cells that closely simulate nature, specifically, photosynthesis. They are also potentially more affordable and more environmentally friendly than existing silicon-based solar cells.

Whichever technology wins out in the end they all will aid in the advancement of this next generation of solar energy collectors. The exciting research being done today is what drives the solar energy industry into the future, and what a bright future it is.

Solar Thermal Use “Heats Up” in Colder Climes

Photo courtesy of DOE/NREL & Craig Christensen

Many people associate solar energy with hot regions like Arizona and Southern California. However, solar thermal water heating (SWH) can be used by families and firms in colder areas, such as Wisconsin and Oregon. In fact, Germany is a solar thermal market leader in Europe.

Borrego Solar Completes 3.4 MW Solar Power Installation at Edwards Air Force Base

© 2012 Borrego Solar Systems, Inc.

SAN DIEGO, Calif.–February 28, 2012—Borrego Solar Systems, Inc., a leading designer, installer and financier of grid-tied government solar photovoltaic (PV) systems, today announced the completion of a 3.4 megawatt (MW) solar power installation at Edwards Air Force Base in Southern California. Comprised of 3 ground-mounted, single-axis tracking solar farms, the system is the largest military project completed by Borrego Solar to date, and demonstrates the value of the company’s end-to-end solar power installation services for military facilities.

The system was financed via Borrego Solar’s in-house Power Purchase Agreement (PPA). Per the agreement, Borrego Solar financed, designed and installed the system at no upfront cost to Edwards Air Force Base. Borrego Solar will sell energy back to Edwards Air Force Base at an economical and fixed rate, offsetting an average of 6 percent of the energy consumption across the three facilities.

“As we work to reduce our dependence on fossil fuels, solar energy is one of the most reliable and cost-effective tools available to us,” said Ms Amy Frost, Chief of the Civil Engineer Asset Management Branch for Edwards Air Force Base. “Financing large-scale projects can be tough in this economic climate, so a PPA made a lot of sense for us, as it eliminated the need for upfront investment and long term maintenance. The deal allowed us to quickly implement solar on our facility and deliver immediate operational savings.”

Scaling up efforts such as this to promote energy security, the Department of the Army recently established the Energy Initiatives Task Force (EITF) to oversee the Army’s goal of transitioning to 25 percent renewable energy use by 2025. Despite the Army’s goals, financing solar projects can still be a challenge. By entering into a PPA with Borrego Solar, military facility managers can move solar projects forward, and enjoy many of the benefits of solar energy while investing zero upfront capital costs.

“We are proud to have completed this project as it is a great example of how public-private partnerships can succeed and allow the development and installation of large-scale solar energy systems on government property,” said Mike Hall, CEO of Borrego Solar. “Edwards Air Force Base should be applauded for making renewable energy a priority at their facility. We look forward to continuing our work with military facility managers to help them take full advantage of the financial benefits that come from using solar to generate clean and sustainable energy, and local jobs.”

Borrego Solar continues to deliver on its mission to help federal organizations go solar. Last week, the company was awarded a contract by the General Services Administration (GSA), certifying it to provide solar installation services to federal agencies. Edwards Air Force Base is the largest project in Borrego Solar’s growing military portfolio to date. The company completed a nearly one MW project in 2010 at the Point Loma Navy Base in San Diego Bay.

Homeowners Use the Sun and Incentives to Save on Winter Heating Costs

Fluctuating energy costs can make it difficult for homeowners to budget their heating bills during the cold winter months.  That is why many are looking into alternative sources of energy for water heating.  One source that is gaining popularity is solar thermal energy, a system that uses energy from the sun to heat a water “tank” that then distributes the warmed water throughout the home. A solar thermal energy system can save money over the long run, and there are government programs that can help reduce installation costs in the short run.

“Solar thermal utilizes the sun’s energy to create heat, so the operating price remains steady over time compared to conventional heat sources,” said Nigel Cotton, Solar Water Heating Global Leader of the International Copper Association (ICA) and founder of Solarthermalworld.org, a web portal for solar thermal professionals.

Cotton went on to explain that most solar thermal hot water heating systems in the home reduce dependence on conventional energy sources over the long-run, but there is an upfront installation cost which needs to be recognized.  That is why it pays to learn about the variety of governmental programs that homebuyers can take advantage of to reduce the cost of installation.

The Federal Investment Tax Credit (ITC) currently offers those installing a solar thermal system a 30% tax credit on the cost of their system. Locally, one common incentive is the Property Assessed Clean Energy (PACE) program, which allows municipalities to finance installations through property taxes.  To find out more click here.

“Installing a solar thermal system is attractive to many people because it utilizes a renewable natural resource—the sun— to provide warmth,” concluded Bärbel Epp, Solarthermalworld.org newsletter editor. “Assuming that energy prices continue to rise, solar heating systems create a lasting financial benefit for families.”

About SolarThermalWorld.org:

Solarthermalworld.org is a global knowledge-based web portal for solar thermal professionals. It offers the latest news and information on the development of the international solar thermal sector. This website forms a worldwide forum for experts on solar thermal technology and those interested in the development of the market. It is hosted by the Global Solar Thermal Energy Council (GSTEC).

UCLA engineers create tandem polymer solar cells that set record for energy-conversion

In the effort to convert sunlight into electricity, photovoltaic solar cells that use conductive organic polymers for light absorption and conversion have shown great potential. Organic polymers can be produced in high volumes at low cost, resulting in photovoltaic devices that are cheap, lightweight and flexible.

In the last few years, much work has been done to improve the efficiency with which these devices convert sunlight into power, including the development of new materials, device structures and processing techniques.

In a new study, available online this week in the journal Nature Photonics, researchers at the UCLA Henry Samueli School of Engineering and Applied Science and UCLA’s California Nanosystems Institute (CNSI) report that they have significantly enhanced polymer solar cells’ performance by building a device with a new “tandem” structure that combines multiple cells with different absorption bands. The device had a certified power-conversion efficiency of 8.62 percent and set a world record in July 2011.

Further, after the researchers incorporated a new infrared-absorbing polymer material provided by Sumitomo Chemical of Japan into the device, the device’s architecture proved to be widely applicable and the power-conversion efficiency jumped to 10.6 percent — a new record — as certified by the U.S. Department of Energy’s National Renewable Energy Laboratory.

By using cells with different absorption bands, tandem solar cells provide an effective way to harvest a broader spectrum of solar radiation. However, the efficiency doesn’t automatically increase by simply combining two cells. The materials for the tandem cells have to be compatible with each other for efficient light harvesting, the researchers said.

Until now, the performance of tandem devices lagged behind single-layer solar cells, mainly due to this lack of suitable polymer materials. UCLA Engineering researchers have demonstrated highly efficient single-layer and tandem polymer solar cells featuring a low-band-gap–conjugated polymer specially designed for the tandem structure. The band gap determines the portion of the solar spectrum a polymer absorbs.

“Envision a double-decker bus,” said Yang Yang, a professor of materials science and engineering at UCLA Engineering and principal investigator on the research. “The bus can carry a certain number of passengers on one deck, but if you were to add a second deck, you could hold many more people for the same amount of space. That’s what we’ve done here with the tandem polymer solar cell.”

To use solar radiation more effectively, Yang’s team stacked, in series, multiple photoactive layers with complementary absorption spectra to construct a tandem polymer solar cell. Their tandem structure consists of a front cell with a larger (or high) band gap material and a rear cell with a smaller (or low) band gap polymer, connected by a designed interlayer.

When compared to a single-layer device, the tandem device is more efficient in utilizing solar energy, particularly by minimizing other energy losses. By using more than one absorption material, each capturing a different part of the solar spectrum, the tandem cell is able to maintain the current and increase the output voltage. These factors enable the increase in efficiency, the researchers said.

“The solar spectra is very broad and covers the visible as well as the invisible, the infrared and the UV,” said Shuji Doi, research group manager for Sumitomo Chemical. “We are very excited that Sumitomo’s low–band gap polymer has contributed to the new record efficiency.”

“We have been doing research in tandem solar cells for a much shorter length of time than in the single-junction devices,” said Gang Li, a member of the research faculty at UCLA Engineering and a co-author of the Nature Photonics paper. “For us to achieve such success in improving the efficiency in this short time period truly demonstrates the great potential of tandem solar cell technology.”

“Everything is done by a very low-cost wet-coating process,” Yang said. “As this process is compatible with current manufacturing, I anticipate this technology will become commercially viable in the near future.”

This study opens up a new direction for polymer chemists to pursue designs of new materials for tandem polymer solar cells. Furthermore, it indicates an important step towards the commercialization of polymer solar cells. Yang said his team hopes to reach 15 percent efficiency in the next few years.

Yang, who holds UCLA’s Carol and Lawrence E. Tannas Jr. Endowed Chair in Engineering, is also faculty director of the Nano Renewable Energy Center at the California NanoSystems Institute at UCLA.

The study was supported by the National Science Foundation, the U.S Air Force Office of Scientific Research, the U.S. Office of Naval Research and the U.S. Department of Energy, together with the National Renewable Energy Laboratory.

Sumitomo Chemical is one of Japan’s leading chemical companies, offering a diverse range of products globally in the fields of basic chemicals, petro-chemicals, IT-related chemicals and materials, agricultural chemicals, and pharmaceuticals. The company’s consolidated net sales for fiscal year 2010 were $23.8 billion.

The UCLA Henry Samueli School of Engineering and Applied Science, established in 1945, offers 28 academic and professional degree programs and has an enrollment of more than 5,000 students. The school’s distinguished faculty are leading research to address many of the critical challenges of the 21st century, including renewable energy, clean water, health care, wireless sensing and networking, and cybersecurity. Ranked among the top 10 engineering schools at public universities nationwide, the school is home to nine multimillion-dollar interdisciplinary research centers in wireless sensor systems, nanoelectronics, nanomedicine, renewable energy, customized computing, and the smart grid, all funded by federal and private agencies.
(www.engineer.ucla.edu | www.twitter.com/uclaengineering)