A new technology created by researchers from Caltech, and described in a paper published online in the October 30 issue of Science Express, represents a first step toward harnessing that lost energy.

Sunlight is composed of many wavelengths of light. In a traditional solar panel, silicon atoms are struck by sunlight and the atoms’ outermost electrons absorb energy from some of these wavelengths of sunlight, causing the electrons to get excited. Once the excited electrons absorb enough energy to jump free from the silicon atoms, they can flow independently through the material to produce electricity. This is called the photovoltaic effect — a phenomenon that takes place in a solar panel’s photovoltaic cells.

Although silicon-based photovoltaic cells can absorb light wavelengths that fall in the visible spectrum — light that is visible to the human eye — longer wavelengths such as infrared light pass through the silicon. These wavelengths of light pass right through the silicon and never get converted to electricity — and in the case of infrared, they are normally lost as unwanted heat.

«The silicon absorbs only a certain fraction of the spectrum, and it’s transparent to the rest. If I put a photovoltaic module on my roof, the silicon absorbs that portion of the spectrum, and some of that light gets converted into power. But the rest of it ends up just heating up my roof,» says Harry A. Atwater, the Howard Hughes Professor of Applied Physics and Materials Science; director, Resnick Sustainability Institute, who led the study.

Now, Atwater and his colleagues have found a way to absorb and make use of these infrared waves with a structure composed not of silicon, but entirely of metal.

The new technique they’ve developed is based on a phenomenon observed in metallic structures known as plasmon resonance. Plasmons are coordinated waves, or ripples, of electrons that exist on the surfaces of metals at the point where the metal meets the air.

While the plasmon resonances of metals are predetermined in nature, Atwater and his colleagues found that those resonances are capable of being tuned to other wavelengths when the metals are made into tiny nanostructures in the lab.

«Normally in a metal like silver or copper or gold, the density of electrons in that metal is fixed; it’s just a property of the material,» Atwater says. «But in the lab, I can add electrons to the atoms of metal nanostructures and charge them up. And when I do that, the resonance frequency will change.»

«We’ve demonstrated that these resonantly excited metal surfaces can produce a potential» — an effect very similar to rubbing a glass rod with a piece of fur: you deposit electrons on the glass rod. «You charge it up, or build up an electrostatic charge that can be discharged as a mild shock,» he says. «So similarly, exciting these metal nanostructures near their resonance charges up those metal structures, producing an electrostatic potential that you can measure.»

This electrostatic potential is a first step in the creation of electricity, Atwater says. «If we can develop a way to produce a steady-state current, this could potentially be a power source. He envisions a solar cell using the plasmoelectric effect someday being used in tandem with photovoltaic cells to harness both visible and infrared light for the creation of electricity.

Although such solar cells are still on the horizon, the new technique could even now be incorporated into new types of sensors that detect light based on the electrostatic potential.

«Like all such inventions or discoveries, the path of this technology is unpredictable,» Atwater says. «But any time you can demonstrate a new effect to create a sensor for light, that finding has almost always yielded some kind of new product.»

This work was published in a paper titled, «Plasmoelectric Potentials in Metal Nanostructures.» Other coauthors include first author Matthew T. Sheldon, a former postdoctoral scholar at Caltech; Ana M. Brown, an applied physics graduate student at Caltech; and Jorik van de Groep and Albert Polman from the FOM Institute AMOLF in Amsterdam. The study was funded by the Department of Energy, the Netherlands Organization for Scientific Research, and an NSF Graduate Research Fellowship.

At a sagebrush-strewn industrial park outside of Reno, Nevada, bulldozers are clearing dirt for Tesla Motors Inc.’s battery factory, projected to be the world’s largest.

Tesla’s founder, Elon Musk, sees the $5 billion facility as a key step toward making electric cars more affordable, while ending reliance on oil and reducing greenhouse gas emissions. At first blush, the push toward more electric cars looks to be positive for utilities struggling with stagnant sales from energy conservation and slow economic growth.

Yet Musk’s so-called gigafactory may soon become an existential threat to the 100-year-old utility business model. The facility will also churn out stationary battery packs that can be paired with rooftop solar panels to store power. Already, a second company led by Musk, SolarCity Corp., is packaging solar panels and batteries to power California homes and companies including Wal-Mart Stores Inc.

“The mortal threat that ever cheaper on-site renewables pose” comes from systems that include storage, said Amory Lovins, co-founder of the Rocky Mountain Institute, a Snowmass, Colorado-based energy consultant. “That is an unregulated product you can buy at Home Depot that leaves the old business model with no place to hide.”

J.B. Straubel, chief technology officer for Palo Alto, California-based Tesla, said the company views utilities as partners not adversaries in its effort to build out battery storage. Musk was not available for comment.

The Tesla systems are arriving just as utilities begin to feel increasing pressure worldwide from the disruption posed by renewable energy.

Lima Meeting

In Germany, the rapid rise of tax-subsidized clean energy has undermined wholesale prices and decimated the profitability of coal and natural gas plants. Germany’s largest utility EON SE said last week it will spin off its fossil-fuel plant business to focus on renewables in part because of new clean energy competitors coming onto its turf.

Threats to the traditional utility model come as energy and environment take the world stage at the latest round of United Nations climate talks that began Dec. 1 in Lima. Delegates, backed by global environmental groups, want to leave the conference with a draft agreement to tackle climate change by lowering carbon-dioxide emissions — something that has eluded them for years.

The Rocky Mountain Institute’s Lovins has installed solar on his house in Snowmass and uses it to power his electric car. His monthly electric bill: $25. He has a lot of company.

100,000 Plug-ins

In California, where 40 percent of the nation’s plug-in cars have been sold, about half of electric vehicle owners have solar or want to install it, according to a February survey by the Center for Sustainable Energy, a green-energy advocate. More than 100,000 plug-ins have been sold in California, according to data from HybridCars.com and Baum Associates, though EVs make up less than 1 percent of all U.S. car sales.

Few homes and businesses use solar and back-up-battery storage, proof for some utilities that the systems remain a hard sell outside of states like California or markets like Hawaii where high power costs make solar competitive.

Still, the Edison Electric Institute, a trade group representing America’s investor-owned utilities, recently announced that its members will help to encourage electric vehicle use by spending $50 million annually to buy plug-in service trucks and invest in car-charging technology.

“Advancing plug-in electric vehicles and technologies is an industry priority,” said EEI President Thomas Kuhn.

Charging Stations

Analysts think the industry has been slow to react. Tesla, SolarCity and green-energy companies are already moving aggressively into unoccupied space. “Some of the more nimble companies that think and move more quickly, they are beating the utilities to the punch,” said Ben Kallo, a San Francisco-based analyst for Robert W. Baird Co.

Tesla has installed 135 fast-charging stations, some powered by solar, across North America where its Model S drivers can refuel for free. NRG Energy Inc. is building a network of public charging stations in major cities that drivers can access on a per-charge basis or for a flat monthly fee of about $15.

And then there’s the home front. In a July report, Morgan Stanley said Tesla’s home and business energy-storage product could be “disruptive” in the U.S. and in Europe as customers seek to avoid utility fees by going “off-grid.”

‘Sufficient Appreciation’

“We believe there is not sufficient appreciation of the magnitude of energy storage cost reduction that Tesla has already achieved, nor of the further cost reduction magnitude that Tesla might be able to achieve once the company has constructed its ‘gigafactory,’” Morgan Stanley analysts wrote.

Tesla sees itself taking on a grand mission — not just to lower emissions from cars and trucks, but to have a societal impact. “If we only do it on the transportation side, we ignore the utility side, and we are probably ignoring half of our responsibility,” said Mateo Jaramillo, director of powertrain business development at Tesla Motors, at the recent Platts California Power and Gas Conference in San Francisco.

Considering further retaliation against Chinese solar dumping, the U.S. Commerce Departments’s International Trade Commission today held hearings in Washington advancing the final phase of its countervailing duty and antidumping duty investigations. Since its imposition of preliminary anti-dumping and counterveiling duties ranging from 30 to 250 percent, Commerce has expanded the case’s scope to include any products assembled in China, regardless of where the bulk of manufacturing occurred, including Taiwan. Final comments to the ITC are due January 15, 2015.

“The worsening solar dispute between the United States and China threatens the future progress of solar energy in America.” — Rhone Resch, president and CEO of SEIA.

Wiley Rein’s Timothy Brightbill, the petitioner in the case for SolarWorld and others, assessed the net impact of the dumping on the U.S. solar industry in January, suggesting that, “According to the China Chamber of Commerce for Import and Export of Machinery and Electronic Products (CCCME)’s Secretary-General, ‘70 percent of the companies that export to the U.S. market are now using Taiwan-manufactured solar cells’ — [meaning that] solar firms face total eclipse in the United States.” Other petitioners in the case were Silicon Energy and PetersenDean.

Respondents in the case included Walter Spak, from White Case and Richard Weiner, from Sidley Austin. Weiner represented the CCCME; Canadian Solar; Trina Solar; StrataSolar; SunEdison and Economic Consulting Services. Other opponents to the case included: John Smirnow, the vice president of Trade Competitiveness at the Solar Energy Industries Association (SEIA); tenKsolar, Neo Solar Power; Gintech Energy; Solartech Energy; Winaico and Moore Energy. 

Testifying on behalf of SolarWorld, Seth Kaplan, of Capital Trade, noted that 3,178 jobs in solar cell production have been lost as a result of the China solar dumping. The losses were reported as a result of plant shutdowns and/or bankruptcies. The figure included 1,831 jobs in multicrystaline cells encompassing losses at: Calisolar; Evergreen; Kyocera; MX Solar; Siliken USA; Solar Power Industries; Spectrawatt; and Sharp. The cumulative figure also included 588 jobs from monocrystaline producers encompassing losses at: Helios Solar, Sanyo, Schott Solar and Transform Solar. And the total also included 759 jobs lost to multi and mono producers BP Solar, Solar World and Solon.

On the other side of the issue, Paula Stern, ex-chairwoman of the ITC and the founder of the Stern Group, international trade advisors based in Washington, blogged in The Hill on December 5 that “The Commerce Department should wake up before it walks off a cliff and inserts fatal legal and trade policy flaws into its decision, sideswiping at least two American companies — Suniva Inc. and Hanwha Q CELLS USA (my firm represents Hanwha Q CELLS) — that make solar products outside of China.”

Stern warned that “Commerce’s novel expansion of the case would be an unprecedented departure from past practice, which could run afoul of U.S. commitments at the World Trade Organization (WTO). The move would also change the rules in the middle of the game for U.S. solar companies that had made business decisions according to decades of settled case law.» 

Rhone Resch, president and CEO of SEIA in July warned that “the worsening solar dispute between the United States and China threatens the future progress of solar energy in America.”

Guests huddled under the more than 1,300 panels that serve as a carport on 2.5 acres of OUC property. The 400-kilowatt (kW) array was commissioned in October 2013 to the delight of 39 customers that each purchased up to 15 1-kW blocks of the system. This equates to up to 1,680 kWh monthly per customer — the average OUC customer uses about 1,200 kWh per month.

OUC signed a 15-year power purchase agreement (PPA) with project developer ESA Renewables at a rate of $0.18/kWh. OUC subsidizes the rate and sells it for $0.13/kWh — about $0.03 higher than local traditional electricity rates — which is locked in for 25 years. Any electricity that they do not use in a given month is rolled over into the next month. Customers agree that they will stick with the program for at least two years, and then they may opt out after paying a small fee. 

Though the carport was likely more costly than installing a rooftop or ground-mounted array, OUC wanted the 39 customers to be able to see the installation and “get that feeling of ownership,” said OUC project engineer Eva Reyes, which is why it started the community solar program in the first place.

“OUC is a municipality supported by taxpayers, so our first purpose is to help customers, especially if they can’t install solar themselves,” explained Reyes. “This could be due to renting, tree overhang, an incorrect-facing roof, or they simply can’t afford it. This way they can have all the benefits of solar as if it was directly on their roof.”

The array was built on aluminum racking rather than steel in order to withstand the 150-mph winds that commonly threaten the region during hurricane season, according to Javier Latre, chief technical officer at ESA Renewables. The installation also uses both a PVPowered central inverter for about two thirds of the system and CPS string inverters for the last third. The inverters were part of a cash grant incentive, which allowed developers to install both types of technologies. The string inverters are ideal for tight, modular spaces, said Latre, and “it is also very on-trend right now to install string inverters for systems under 1 megawatt.”

The carport also includes two electric vehicle charging stations, which both use solar power produced directly from the carport. One of which is a fast-charging station that can charge a battery 80 percent in just 30 minutes.

Due to the popularity of the community solar program, OUC is already planning a second installation in the coming year, which has already amassed a waiting list, according Reyes. OUC will release a request for proposals (RFP) in early 2015 and hopes to start construction in the summer.

After attendees got their fill of solar knowledge for the morning and opened their umbrellas to head back to the bus, Latre looked on the brightside: “You know, there is one positive thing about this rain — it’s just mother nature’s way of cleaning the solar panels for us so we don’t have to bother.”

Click next to view a photo slideshow of the tour.

Orlando —

On Monday evening during PennWell’s Annual Awards Gala, Ivanpah was named the 2014 Renewable Energy Project of the Year.

Editors from Renewable Energy World and Power Engineering selected the winner from among the five finalists. The winner was announced and recognized at the co-located Renewable Energy World North America Conference and Expo and Power-Gen International in Orlando, Florida during the Annual Awards Gala on Monday night.

To be eligible for an award, a project needs to have been commissioned between August 1^st, 2013 and July 31^st, 2014 and have made a significant impact on the entire renewable energy industry.  When judging the finalists, network editors considered the technology that was employed as well as the projects’ impact on the industry at large and on the communities in which they were installed.

Located in California’s Mojave Desert, Ivanpah is a shining example of renewable energy progress, as evidenced by the fanfare at its dedication. Esteemed guests included representatives from not only its creators at Bechtel, NRG Energy and Brightsource and financiers from the DOE and Google, but also Grammy-nominated rock band The Fray, which used the project as a backdrop for their album cover and recent music video.

Ivanpah uses 173,500 heliostat mirrors that focus sunlight on several centralized power towers.  The towers generate steam to drive specially adapted 123-MW Siemens steam turbines — the largest fully solar-powered turbines in the world. In order to reduce its environmental impact, Ivanpah also utilizes dry cooling to condense the steam back into water, which minimizes water consumption to just 0.03 gallons of water per kW of electricity generated.

The project is a concentrating solar power success story and is well deserving of the prestigious award.

Martifer Solar, a subsidiary of Martifer SGPS, has delivered one of the first unsubsidized solar power plants in Italy for the Ikea Group on the rooftop of a new commercial store in Pisa, Tuscany. The project has a total capacity of 696.15 kWp and has been structured without a feed-in-tariff approach.

Simo, the first commercial wind farm equipped with Gamesa’s 4.5 MW wind turbines, has been commissioned in Finland, where the company has installed four G128-4.5 MW machines for TuuliWatti. Specifically designed to withstand low temperatures, these four wind turbines in Simo are the most powerful turbines ever installed in Finland, Gamesa reports.

After the coastal states Egypt and Morocco, Ethiopia is Africa’s third largest wind power user. Neighbouring Kenya is also preparing to harness more of the wind.

Walking through the Ethiopian capital Addis Ababa, one notices diesel generators rattling outside of many shops. A photo­grapher has to send customers to his competitor because he has not protected himself against power cuts like many other shop owners. There is no system for back-up power at his shop.
The state-owned Ethiopian energy utility EEPCo is located just a few steps away. Unlike Kenya’s largest majority state-owned energy utility KenGen, EEPCo manages the whole country’s energy supply and therefore operates all the wind farms. That includes the 34 wind turbines of Adama 1, which have been ­rotating at a height of around 1,800 m three kilo­metres from Adama since 2012 with a total capacity of 51 MW.

With this wind farm, Ethiopia has overtaken its neighbour Kenya in terms of wind energy in one fell swoop. Last year, another 120 MW was added at the Ashegoda wind farm 775 km north of Addis Ababa, taking the East African country to number three on the continent. In its 2013 market analysis, the ­German Energy Agency (dena) specified Ethiopia as a future market for onshore wind.

Things are happening in Kenya

By comparison, with 5.1 MW in the Ngong Hills outside its capital Nairobi, Kenya is a lightweight – in fact, along with South Africa, it is in the “Others” ­category in the Global Wind Energy Council’s (GWEC) 2013 annual report. Although the six 850 kW Vestas turbines in Ngong went into operation in 2009, it has taken years for KenGen to work on expansion. Plans for extensive use of geothermal energy in the East ­African Rift Valley take precedence. In the long run, it is not wind but geothermal energy that is to replace hydropower as the top electricity source.

In late July 2014, a Spanish consortium made up of Iberdrola and Gamesa completed the installation of 16 Gamesa turbines, each with a capacity of 850 kW, in Ngong. Nearby, TPF-Econoler of Belgium equipped a wind farm with eight 850 kW Vestas turbines. This increases KenGen’s generation capacity in Ngong to 25.5 MW. According to media reports, the inauguration ceremony for both projects is to take place in autumn.

General Electric is supplying some 38 turbines of 1.6 MW each for the wind farm on the Kinangop ­Plateau, which is 2,000 m high and located 60 km northwest of Nairobi. Installation started in May 2014. As local media reported in July, construction has been delayed because of a dispute about compensation for farmland that the Kinangop Wind Farm consortium intends to use. However, GE Renewable Energy’s General Manager Europe Cliff Harris firmly believes that results will be visible in February 2015.

Great potential – and high risk

The 300 MW wind farm project at Lake Turkana in northwestern Kenya in particular demonstrates that transport logistics and financial risks play a key role when building wind farms – promising wind yields are not the only important factor. Because of lacking grid infrastructure and high costs and risks, the World Bank quit the project in 2012. “We were aware of these concerns,” project head Carlo van Wageningen of the Netherlands explained in a TV interview in late March. Van Wageningen’s consortium has now finalised the financing documents for a loan of € 623 million with the African Development Bank (AfDB), the European Investment Bank (EIB) and international lenders. Unlike the World Bank, the AfDB believes in the project that was launched in 2005, Van ­Wageningen states, pointing out the benefits of the future Lake Turkana Wind Power Project.

He says that the annual average wind speed on site is 11.8 m/sec, and the continual wind between 7 and 19 m/sec ensures that electricity yields near the base load range would be possible. At the same time, however, Van Wageningen warns that there is more to consider: “Although the financing is closed, we will not start work for the obvious reason that we do not want to bear the whole risk for being ready before the transmission lines for power distribution have been laid.” According to the plan, the 365 Vestas wind turbines will go online in 2016. Another major challenge is transporting turbines and rotor blades 1,000 km from the port of Mombasa to Kenya’s remote northwest.

The Lake Turkana Wind Power Project consortium includes KPP Africa B.V., Aldwych International Ltd., Vestas Wind Systems A/S and a Norwegian, a Danish and a Finnish fund. The consortium is responsible for the financing, installation and operation of the wind farm. In its capacity as an energy company focussing on Africa, Aldwych will supervise the wind farm’s installation and operation, while Vestas will take on the maintenance and, of course, delivery of the wind turbines. Kenya Power (KPLC) will buy the electricity generated at a fixed price over a time span of 20 years. It is here that the Kenyan feed-in tariffs for wind energy will pay off; Ethiopia is still waiting for such a policy.

Logistical and technical challenges

Still, Ethiopia and Adama 1 will remain the ones to look up to in East Africa for the time being, especially some 153 MW are being installed nearby at Adama 2. Adama is located 99 km southeast of the capital and lies on the main road leading to Djibouti, the small country on Africa’s eastern coast where all goods including turbines and rotor blades are handled in the port. Heavy-goods vehicles then transport them to the wind farm. 

One morning, wind turbines on the hillsides outside Adama are at a standstill. There are problems with transmitting power via the national grid, according to engineers from Chinese turbine supplier ­Goldwind and operator EEPCo, who explain that during grid bottlenecks the electricity from hydropower plants has priority. After all, they provide approximately 90 % of the electricity produced in the country.

There is intense activity in the control centre. In the end, the computer screen shows that all wind turbines except two are once again sending electricity to the grid. Because remote switching did not succeed in restarting the last two turbines, service personnel need to head out in their 4 x 4 vehicle in order to switch them on again manually.

Experience stimulates growth

In Aysha, at the Ethiopian border to Djibouti, a 300 MW wind farm is in the works. It is slated to be completed by the time the five-year plan for growth and transformation expires in late 2015. However, negotiations are still on­going to finance the three project phases. “Our company and Dongfang of China will install 120 MW each,“ explains Senior ­Advisor Stephan Willms of Lafto Turbine Technologies, a German company based in Addis Ababa, adding that the local technology company METEC will be in charge of the remaining 60 MW.

According to press reports, the Chinese Export-Import Bank EXIM, which was already part of the Adama deal, is named as a lender for a project phase.  The parties that will be involved on the European side are still being discussed. After Adama and Ashegoda, the port of Djibouti has experience loading large wind turbines, which should make it easier to handle equipment for Aysha. In addition, roads and power transmission lines are already available.
For Ashegoda wind farm about 750 km needed to be covered on the road for ­Vergnet’s 30 GEV HP two-bladers with 1 MW of capacity each and the 54 Alstom ECO74 three-bladers with 1.67 MW each. As of the end of May 2014, almost all wind turbines of the wind farm are in regular operation, according to information from German project specialist Lahmeyer.

By 2030, Kenya and Ethiopia intend to increase power generation capacity by more than tenfold in order to make their vision of becoming emerging markets come true. While Kenya expects 3,000 MW of wind energy capacity to be built, amounting to a share of about 15 % in the generation mix, figures in Ethiopia reach up to 7,000 MW, which would raise the share of wind power capacity to more than 30 %. Wind farms ­already rank second behind hydropower plants. While the envisaged rise to more than 800 MW by late 2015 may seem to be an expression of very ambitious aspirations, doubling the wind power capacity within the next two years seems to be quite realistic. This would be quite in line with logistics experience, advances in ­installation and promising project financing negotiations.

In Kenya, the extent to which Turkana will be completed by the end of 2016, or how projects such as Kipeto (on the coast) and Isiolo will do with their 100 MW each, is as yet unknown. In order to attract more investors to the country and implement large projects, Ethiopia’s government will have no choice but to approve independent generation companies, in addition to EEPCo, and establish an energy market.

Josephine Bollinger-Kanne