Blythe Solar Project

For instance, an installation of 1800 panels on an NREL building generates 240 W from each. Installing 1.6 MW of PV panels certainly factors into the overall cost of the building and could affect other energy saving features. For example, construction costs are always a hot button. To bring them down, one company manufactures its preconfigured PV panels in 1-MW units. To reduce shipping related losses and damage, the units will be assembled on site in a clean tent and carried to mounting hardware a few yards away. Furthermore, those units are said to weigh about 40% less than conventional designs, so handling them is easier and less labor intensive.

The U.S. Department of Energy announced support for energy-saving commercial building projects as part of its ongoing effort to improve the energy efficiency of buildings in the United States. DOE’s national laboratories will select and fund technical experts to provide guidance to commercial building owners and operators. The goal of this Commercial Building Partnerships (CBP) initiative is to increase the energy efficiency of selected new and existing buildings.

The partnership will foster collaborative relationships among the owners and operators of commercial buildings, researchers from DOE national laboratories and private-sector technical experts. Building owners receive technical expertise on how to design, build and maintain low-energy buildings that can reduce energy use and lower energy bills across their buildings. These collaborations are to move energy-saving strategies into the marketplace quickly and cost-effectively. Each of the building projects will be documented in publicly available case studies that will provide detailed energy use data and best practices to other building operators across the country.

Three DOE national laboratories are managing this new effort: the National Renewable Energy Laboratory (NREL) in Golden, Colo., the Lawrence Berkeley National Laboratory in Berkeley, Calif., and the Pacific Northwest National Laboratory in Richland, Wash.

“Partnership participants will create buildings with measured energy savings of at least 50% for new construction and 30% for existing buildings,” said Paul Torcellini, group manager for commercial building research at NREL. “This initiative is unique because it demonstrates that it’s cost-effective to make buildings more energy efficient, and that energyefficient buildings are easy to replicate.” Applicants can apply through the laboratories for the following two initiatives:

The second installation example comes from the Department of the Interior. To boost construction, the Department has approved the largest solar-energy project ever to be built on U.S. public lands. When constructed, the Blythe Solar Power Project will produce up to 1,000 MW of solar power. The project will cover 7,025 acres of public lands eight miles west of Blythe in Riverside County, California. It is expected to create 1,066 jobs at the peak of construction and 295 permanent jobs.

The Blythe Solar Power Project uses concentrating parabolic trough equipment in which parabolic mirrors focus solar energy on collector tubes which carry heated oil to a boiler that generates steam for a turbine to produce electricity. A 230-kV transmission line will be constructed to connect the project to the Devers- Palo Verde #2, a 500-kV line at the Colorado River substation.

“The Blythe Solar Power Project is a major milestone in our nation’s renewable energy economy and shows that the United States intends to compete and lead in the technologies of the future,” Secretary Ken Salazar said in signing the Record of Decision. “This project shows in a real way how harnessing our own renewable resources can create good jobs here at home.”

One government official says solar projects constructed on BLM public lands in the last few weeks have potential to generate up to 2,800 MW of renewable energy.

The Blythe Solar Power Project would be the largest concentrated solar power facility in the world. Combined, the four 250-MW plants will deliver 1,000 MW of nominal generating capacity.

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One panel version uses a sputtered, blue-copper absorber surface. The extruded aluminum frame is welded on each corner with an electrostatic powdercoat finish. Polyurethane hard-foam insulation minimizes heat loss. Such panels are often available in 4 x 8 ft, and 4 x 10 ft sizes.

One hybrid photovoltaic-thermal collector combines functions of both into one panel. It simultaneously produces electricity and hot water.

One manufacturer of commercial solar thermal systems specializes in 65 to 130 ft. collectors with features such as a PVD coating for best solar absorption, a laser welded absorber and serpentine heat-transfer system, and materials that exhibit low heat loss and high insulation values. The company adds that the equipment is versatile so that it mounts on a roof or stand on the ground. A weather-resistant anthracite powder coated aluminum frame ensure a long useful working life, and the company backs that claim up with a 10-year warranty and SRCC-OG100 certification.

The flat plate collector is available as a single-piece large collector. Manufacturers may also offer a variety of light-duty commercial solar thermal collectors, storage tanks, controls, and accessories for a single source solar package.

Another solar equipment manufacturer offers thermal solar equipment in low-pressure and highpressure models. A low-pressure gravity-feed design consists of a vacuum glass tube collector, an insulated storage tank and optional stand parts. The evacuated glass tubes are filled with water and exposed to sun, thus heating the water.

Because the specific gravity of cold water is heavier than hot water, the hot water in the glass tubes rises in the insulated water tank, while cold water in the tank sinks into the glass tubes. As this cycle continues, water in the solar water tank slowly circulates while its temperature rises. The effect, called a thermosyphon, is based on natural convection.

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Without the Arc Guard System an arc flash will typically trip a circuit breaker in approximately one second, enough time for the arc to destroy the switchgear and kill or seriously injure a person. TVOC-2 is now UL listed, and when installed along with ABB’s Emax circuit breakers, carries a functional safety rating of SIL-2 as certified by TÜV Rheinland.

“The SIL-2 rating is especially important because it allows the TVOC-2 Arc Guard system to be used where an engineered safety solution is required,” said Steve Zbytowski, PE, product manager of control gear at ABB.

An arc flash is a strong electric current, and often a major explosion, that passes through air when insulation between electrical conductors is no longer sufficient to contain the voltage within them, creating a short that allows electricity to race from conductor-to-conductor1. Arc flashes can emit heat up to 35,000° F, four times the surface temperature of the sun. It is estimated that five to ten arc flashes occur in the US every day, causing one to two daily fatalities2. Despite conscientious attempts to design systems that inherently reduce risk, mechanical measures often fail because most accidents occur with the switchgear door open, and electrical breaker protection is solely based on delayed over-current stoppages. The main cause of arc flashes is human error and 65% occur when an operator is working on the switchgear.

The system can detect an arc flash in less than one millisecond, and depending on the disconnecting device, it will typically disconnect the power to the switchgear within 30 to 50 milliseconds. This will not prevent the accident, but it will significantly reduce the damage.

The system uses light as the main condition to instantaneously trip the incoming circuit-breaker, responding in milliseconds and overriding slower protection elements. The system acts in three phases:

Detection – on optical sensor senses when light (an arc flash) is inside the equipment

Recognition – the arc monitor determines the intensity of the light

Action – the TVOC-2 sends a signal to trip the breaker(s)

Short circuit protection alone is not enough to provide the necessary response time because power distribution systems often include a required selectivity designed to achieve desired plant efficiencies and ensure power availability. This selectivity delays the breakers tripping in the necessary time. The Arc Guard System, along with properly specified circuit breakers, overrides the protection delays within the necessary timeframes to minimize injuries and equipment damage.

In addition to achieving the functional safety design as approved through rigorous third party testing and certification, the feature upgrades of TVOC-2 provide significant system enhancements, including:

Reliability:
Pre-calibrated optical sensors and fiber optic point sensors
Hardware based self monitoring system for critical functions; the software is used only for supervision and information processing
Wide ranging input voltage ratings (100 to 240 V AC and 100 to 250 V DC)
Selective tripping of only the affected circuit breaker, not all breakers within a system

Flexibility:
The HMI can be mounted on the TVOC-2 or panel door
Standard system has 10 sensor inputs, expandable to 30
The system can be configured according to specification

Simplicity:
User-friendly start-up menu, easy to install
Mounting options on DIN-Rail or directly on a panel wall
Easy to expand as the switchgear grows

The Arc Guard System is also compatible with an extremely wide range of applications, including new or OEM installations, and old equipment soon to be out-of-date without a safety upgrade. It can also be installed on systems of all sizes and values, from $10,000 switchgear up to systems in excess of $1,000,000. Some of the industry segments and applications that can benefit from Arc Guard include substations; critical power facilities such as hospitals and data centers; yachts; cruise and refrigerated container ships; oil rigs; chemical plants; railroad – trains and way stations; steel mills; and wind/solar power facilities.

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1. Intel Corporation: meets 88% of their demand with 2,502,052,000 kWh of biomass, geothermal, small-hydro, solar, wind

2. Kohl’s Department Stores: meets 100% of their demand with 1,524,656,000 kWh of solar and wind

3. Wal-Mart Stores Inc. (California & Texas facilities): meets 28% of their demand with 872,382,088 kWh of biogas, solar and wind

4. Whole Foods: meets 106% of their demand with 800,257,623 kWh with solar and wind

5. Johnson & Johnson: meets 52% of their demand with 553,565,521 kWh of biomass, solar and wind

6. City of Houston, Texas: meets 35% of their demand with 438,000,000 kWh of wind

7. Starbucks: meets  52% of their demand with 421,921,000 kWh of wind

8. City of Austin, Texas: meets 100% of their demand with 406,000,000 kWh of wind

9. Staples: meets 52% of their demand with 341,509,408 kWh of biogas, solar and wind

10. Hilton Worldwide: 94% of their demand with 315,000,000 kWh of various clean energy sources

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A diagram of a parabolic trough solar farm (top), and an end view of how a parabolic collector focuses sunlight onto its focal point. -Andrew Buck

One manufacturer of solar panels produces arrays that combine silicon cells, durable reflector materials in a parabolic trough and single-access tracking into one system. The company says as the solar industry matures, customers are valuing energy yield and cost more than peak “nameplate” rating. The company’s high-gain solar is a series of system-level design features which drive lower installed cost and higher energy yield relative to traditional fixed PV arrays. The equipment, says the company, starts with high-efficiency silicon cells and tracking, which increases energy yield. It now includes reflective materials, lower-cost panels, convection cooling, string and shadow management, and streamlined installation and maintenance.

This concentrating design includes a holder for the cells used on its array so they are easily replaced. This would happen when it makes economic sense, as it will when more efficient cells become available in a few years. Such a panel will let a solar park increase its output and become more useful, a claim few other power production facilities can make.

The concentrated photovoltaics from a German PV manufacturer use lenses to focus direct sunlight onto small, efficient solar cells. This conversion of sunlight into electricity makes it possible to generate about twice the electricity per square meter of module area than traditional flat-panel photovoltaics. The cells are mounted on a structure that tracks the sun on two axes to enable a near constant power output curve. This better matches the peak power demand in arid climates. This CPV technology is intended for areas of high irradiation and a low heat reduction coefficient, making it suitable for large power plants in desert regions.

Because it scales to large plants, companies can design facilities from one to hundreds of megawatts. Other benefits, according to the manufacturer, include attractive rates of return, a design well suited to hot climates, and about double the operating efficiency of conventional PV systems. In fact, a company reported 25% AC-system efficiencies in 2009 and says it is aiming for 35% efficiency.

The modules are also said to have a low environmental impact and minimal water consumption — even a dual land use with agriculture is possible, unlike conventional PV or CPV power plants. These require using the land only for the array. This is a plus in areas where rare animals could impede a project. The equipment is also almost completely recyclable.

Parabolic troughs are also going through rapid changes. Solar concentrators using a parabolic trough on utility scale arrays can harness the sun’s energy to make steam for electricity generation. One utility-scale solar concentrator uses a lightweight mirror film in place of the fragile glass mirrors.

Thermal efficiency for any solar application is the proportion of available sunlight converted into heat to generate electricity. The proportion predicts performance of a given parabolic trough and allows comparing competing technologies. NREL tests show the thermal efficiency of one mirror-film trough in particular at a remarkable 73%. Temperature of the working fluid reaches 350°C (662°F). The efficiency figure means nearly three quarters of the solar radiation striking the trough’s surface is converted into thermal energy. The lab’s results confirm that the design’s performance is comparable to or exceeds that of the previous, proven, utility-grade trough systems at a cost that the lab says is below industry standards.

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Typical Structure of crystalline Silicon solar cells

Generally, monocrystalline cells have higher efficiencies than polycrystalline cells, but the monocrystalline cells are more expensive to manufacture. Drawbacks of conventional photovoltaic systems are the high initial cost and limited electrical output when compared to the solar input. Other developments are coming fast.

Crystalline silicon technology currently makes up about 80% of the market. It uses silicon wafers as its main raw material. Wafers are cut from cast ingots in thin slices with a thickness in the range of 200 to 300 μm.

In crystalline silicon manufacturing, the wafers are processed, interconnected and laminated into a substrate, which is typically made of glass. Commercial-grade solar modules using crystalline silicon technology can convert sunlight to useable electrical energy at a relatively high efficiency ranging from 14% to 19%. Although efficiency is good, this technology can be expensive due to the high cost of the silicon wafers, which make up 40% to 50% of the price of the finished solar module.

Thin-film photovoltaics account for the other 20% of the solar module market. Thin films use no silicon wafers. Instead, photovoltaic material is deposited in a thin layer — typically with a thickness of 1 μm or less — to a glass substrate or a flexible thin metal or plastic substrate.

After deposition, the substrate is processed and separated into individual cells, which are connected in series. Thin-film solar modules only achieve conversion efficiencies in the range of 8% to 10%, but are much less expensive to manufacture because silicon wafers are not required as a raw material. The goal with both technology types is to drive efficiency up and costs down.

The 19% efficiency for PV panels mentioned earlier leave a lot of room for improvement. Researchers at a national lab and one university may be on to the next big step. For example, teams from NREL and the University of Colorado, Boulder (UCB), have reported the first designed molecular system that produces two triplet states from an excited singlet state of a molecule, with what they say is essentially perfect efficiency. The development could lead to a 35% increase in lightharvesting yield in cells for photovoltaics systems.

The experiments, using a process called singlet fission, demonstrated a 200% quantum yield for the creation of two triplets of the molecule 1,3-diphenylisobenzofuran (DPIBF) at low temperatures. In singlet fission, a light-absorbing molecular chromophore shares its energy with a nearby nonexcited neighboring molecule to yield a triplet excited state of each. If the two triplets behave independently, two electron-hole pairs can be generated for each photon absorbed in a solar cell. This process could subsequently increase by one-third the conversion efficiency of solar photons into electricity or solar fuels. The researchers identified DPIBF as a promising candidate while searching for molecular chromophores that have the required ratio of singlet and triplet energy states.

NREL and Los Alamos National Labs had previously demonstrated an analgous two-electrons-from-one photon bonus using semiconductor quantum dots in a process NREL termed Multiple Exciton Generation. The latest advance is the first to demonstrate the electron multiplication phenomenon via the singlet-fission process in molecules.

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The greenhouse includes a system of integrated monitoring that remotely controls the photovoltaic plant, as well as the microclimatic parameters necessary for the citrus grown it houses. Such parameters include relative humidity, temperature, CO2, regulation of the ventilation and irrigation system, etc.

The design of the SOLTEC greenhouses allows the solar radiation into the interior optimizing both the agricultural and the photovoltaic production. The result of both activities is a very cost-effective and environmentally-friendly investment.

The installation will be the object of a study by Danish solar inverter manufacturer, DANFOSS, to develop a Case Study of the 134 TripleLynx inverters installed in the plant.

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EPC Bella Energy chose Solectria Renewables‘ SMARTGRID 500 and 300 commercial and utility-scale inverters to power the project, which will produce about 2.4 MWh annually.  This is expected to eliminate more than 4.3 million pounds of CO2 per year.

“This project took a lot of hard work, but our team assembled a package backed by the highest efficiency and most reliable solar  inverters by Solectria Renewables,” stated Andrew McKenna, VP of Bella Energy. “Bella Energy prides itself on providing the highest quality solar equipment and solutions that power some of the large arrays across the United States.”

“The Salt Palace Convention Center project demonstrates the opportunities of rooftop installations throughout the United States,” said Phil Vyhanek, President of Solectria Renewables. “The progression from small to large rooftop installations has accelerated over the past few years. Solectria Renewables is proud to be part of Salt Lake City’s commitment to renewable energy.”

“Salt Lake County is committed to reducing its energy usage through conservation and the use of renewable technology at its facilities,” said Peter M. Corroon, Mayor of Salt Lake County. “This spring we look forward to producing a significant portion of the Calvin L. Rampton Salt Palace Convention Center’s electrical power with this solar array. We are proud to offer our future convention guests clean power from the largest solar rooftop installation in Utah and one of the largest in the country. This project was made possible by an unprecedented private/public partnership and serves as an example of the significant and untapped solar potential in the state of Utah.”

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In the second of my dispatches, I wrote the following:

An interesting question came up in the same session: Why aren’t more projects being developed in the Southeast? Yes, the irradiation isn’t as high as it is in California, but it’s not as low as New Jersey. The regulations are lower, the hurdles to develop projects are lower — why isn’t anyone coming to the Southeast to bring solar projects to those states? The general consensus of the assembled experts was that the Southeast doesn’t get more business because, though all of the questioner’s points were accurate, there are few — if any — incentives for developers to go there. There’s no notable Renewable Portfolio Standards (which require state utilities to have a portion of their portfolio coming from renewable energy sources), and there are few if any subsidies or incentives (like the Renewable Energy Certificates so popular in other states). That renders projects less profitable in the Southeast than they are in other parts of the country — so developers aren’t coming.

Which elicited this reader comment from a gentleman named Andrew Tomer:

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“We are excited to work with Boots on the Roof to introduce this powerful new solution to the solar industry,” said Joe Scarci, VP of Marketing for SolarBridge. “AC modules powered by SolarBridge microinverters provide the lowest installed cost for rooftop solar. SolarBridge microinverters are designed for high reliability and don’t contain any failure-prone components such as electrolytic capacitors, giving installers confidence that they are implementing a solution they can trust.”

SolarBridge Technologies Pantheon microinverter

SolarBridge says the Roof-ReadyTM AC modules cut field installation time by up to 20% and deliver up to 25% more energy harvest than central inverter-based systems. The company’s Pantheon microinverters are factory-installed on the back of modules by module manufacturers and the entire AC module is backed by a single 25-year warranty.

“Boots on the Roof is committed to educating our students on the latest and most innovative solutions on the market,” said Chuck Rames, program director for Boots on the Roof. “We know that solar technology evolves rapidly and we look to partners like SolarBridge to share information on cutting-edge products such as the SolarBridge AC Module system.”

SolarBridge’s technology will also be featured in Boots’ Commercial Solar Business and Sales and Commercial Solar PV Construction classes.

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(Note to all: I’m just kidding — but I am glad to see someone else picked up on this little subtlety of this  brouhaha other than me.)

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Shayle Kann of GTM Research forecasts that the utility-scale solar market will grow at least 100% in 2012, but noted that a new market may be opening up for solar developers: municipalities.

Kann estimated that there are 2,000 municipalities in the United States (though according the U.S. Census Bureau, there are 19,492), and that they beginning to look seriously at adding renewable energy to their portfolios — to lower electricity rates for their residents, to be “cutting-edge” in the energy field, to bring in new revenues — the reasons for turning to renewable energy are almost as varied as the municipalities themselves.

Anecdotally, I get at least 15 to 20 press releases a day telling me that this town, this city or this school district are building PV installations on their roofs and on municipal-owned land (in fact, in our February issue, we’ll be featuring once such project in our Racking and Mounting section). It seems that these deals are getting done much more quickly and much more easily than traditional utility projects because the financing is easier to get (many of the conference’s speakers noted that the European debt crisis is going to make getting credit difficult for the rest of the year).

This market is one to watch in the future — I know I’ll be watching it carefully. Let me know what you’re seeing out there and if you think Kann’s assessment is correct.

(For more of my thoughts on the Solar Power Generation show, see my live reports here and here.)

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Today’s announcement is Alta’s next step toward commercializing its technology. This new panel uses the same technology as the company announced last summer, which achieved record solar cell conversion efficiencies resulting from key technical breakthroughs in harnessing the high efficiency of gallium arsenide (GaAs) in cost-effective ways.

Alta focused on GaAs because of its intrinsic efficiency advantages as well as its ability to generate electricity at high temperatures and in low light.  This means that Alta’s panels have substantially higher energy density than other technologies, generating more kilowatt-hours of energy over the course of a year in real-life conditions.

In addition to technology advances which push the limits of energy density, Alta is also focused on changing the manufacturing economics of solar and enabling formats and form factors that were previously not possible.

To that end, though GaAs is known for being expensive to produce, Alta has invented a manufacturing technique that enables extremely thin layers of GaAs that are a fraction of the thickness of earlier GaAs solar cells. Alta’s cells are about one micron thick; for comparison, a human hair is approximately 40 microns thick. In utilizing very thin devices that have the highest energy density possible, the cost of the material needed in Alta panels remains low and the potential costs of an entire solar energy system based on Alta’s technology could be dramatically reduced.

Moreover, because Alta’s PV film is thin and flexible, it has the potential to be integrated in wholly unique ways and into a variety of applications – including roof and building materials, and numerous military, consumer, and transportation products.

Alta is making progress on the build-out of its pilot manufacturing line, which uses mostly off-the-shelf equipment with some proprietary optimizations to Alta’s process.  Moreover, Alta is starting to plan for full-scale production, with activities such as building strategic manufacturing partnerships and selecting its first large, commercial manufacturing site.

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• I was fascinated by the presentation by Drew Torbin, vice president of the Renewable Energy Group for Prologis. Prologis is not a solar company; they are a commercial real-estate developer that owns and maintains industrial properties (warehouses, distribution center and the like). So Torbin said the company had an epiphany one day: Prologis has lots of roof space (550 million square feet, to be exact, and 11,000 acres of land worldwide ) and have ideal locations to host solar arrays (flat roofs, anyone?) — but they are really low load facilities, so they don’t need the power for their own uses. So how does a company monetize those assets? Torbin said the company remains the landlord for all the buildings, but they cover them in solar panels — and lease the space to utilities that want to use them to build their arrays. It just goes to show how hot the solar industry is — even the real-estate companies are finding ways to get a piece of the pie.
• An interesting question came up in the same session: Why aren’t more projects being developed in the Southeast? Yes, the irradiation isn’t as high as it is in California, but it’s not as low as New Jersey. The regulations are lower, the hurdles to develop projects are lower — why isn’t anyone coming to the Southeast to bring solar projects to those states? The general consensus of the assembled experts was that the Southeast doesn’t get more business because, though all of the questioner’s points were accurate, there are few — if any — incentives for developers to go there. There’s no notable Renewable Portfolio Standards (which require state utilities to have a portion of their portfolio coming from renewable energy sources), and there are few if any subsidies or incentives (like the Renewable Energy Certificates so popular in other states). That renders projects less profitable in the Southeast than they are in other parts of the country — so developers aren’t coming.
• In the CSP realm, Partho Sanyal of Bank of America Merrill Lynch said that the chances of CSP companies going public are nearly nil in Europe because of the debt crisis. The public markets, he said, have not been kind to solar companies that have gone public — mostly their own fault by not performing as well as expected. It will take more long-term proof and larger CSP projects to establish a track record that the public markets can believe in.
• The inverter panel (made up of John Skibiniski, vice president of Renewable Energy Market Development for American Electric Technologies; Marco Trova, director of technical sales, Renewable Energy Products, Power One Italy and Elie Nasr, business development director, Power Plant Solutions, SMA) all agreed that the inverter market needs more coherent standards worldwide to allow solar farms to be more easily connected to the grid. They all agreed that this lack of standards is holding the inverter market back.
• I had a good opportunity to discuss CPV technology with Wayne Miller of GreenVolts, who discussed their fully integrated CPV system. He explained the ins and outs of the system and showed me some of the projects they’ve produced. So far, they’ve only done about 5 MW in projects, but they’ve attracted the attention of ABB, who has taken 25% interest in the company and is going to help them expand overseas. Miller says he expects their installed megawatts to increase significantly with their new partnership.

Today is the final day of the show, and I’ll give you my final wrap-up on Friday. Stay tuned.

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Sunny Central 500-HE US solar inverter

Currently, the full Sunny Central Compact Power (CP) line—which includes 500-800 kilowatt inverters—and the Sunny Central 500HE-US (assembled in Denver, Colorado) meet the guidelines of the the Buy American clause.

“The addition of the Sunny Central CP line and the Sunny Central 500HE-US completes our portfolio of ARRA-compliant inverters,” said Jurgen Krehnke, president and general manager of SMA America. “Now installers can specify the inverters for all project sizes—residential, commercial and utility-scale—while satisfying ARRA’s Buy American Clause.”

The Sunny Central CP line includes the Sunny Central 500CP, 630CP, 720CP, 760CP and 800CP, which won the Intersolar Award 2010 in the photovoltaics category. The manufacturer says its outdoor-rated Sunny Central CP inverters produce 110 percent of rated output at ambient temperatures below 25 C, resulting in increased yields and a lower levelized cost of energy. Meanwhile, the Sunny Central 500HE-US boasts a maximum efficiency of 98.6 percent.

The UL-certified, ARRA-compliant Sunny Boy 3000-US, 4000-US, 5000-US, 6000-US, 7000-US and 8000-US offer efficiencies of up to 97 percent. The manufacturer says an OptiCool active temperature-management system and rugged cast-aluminum, outdoor-rated enclosure helps increase product life. Automatic grid-voltage detection and an integrated DC disconnect switch simplify installation, ensuring safety while saving time. These Sunny Boy models also feature galvanic isolation and can be used with all types of solar modules—crystalline as well as thin-film. They include a 10-year factory warranty, with the ability to extend up to 20 years.

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