Green Energy

Spurred by record-low equipment costs and state-sponsored incentives, solar installation companies are flocking to Illinois. One of the fast-growing solar markets involves partnering with farmers willing to lease some of their acreage to cultivate solar energy rather than crops.

Dozens or sometimes hundreds of solar panels are lined up in fields, angled to maximize the absorption of the sun’s rays. The energy is transmitted to the nearest power substation and mixed in with the utility’s power supply. It’s become lucrative for both landowners and the solar companies that own and maintain the equipment.

A Minnesota company, Innovative Power Solutions, has several projects in the works in St. Clair County. This week, Belleville issued a special use permit for a four-megawatt installation on land near Eckert’s Farm. The company also got approval from St. Clair County for solar arrays in six locations on a large farm, producing up to 12 megawatts altogether.

The projects are not a done deal, however. IPS is applying for renewable energy credits through the state of Illinois, but the company will need some luck to get them. The program, launched in 2017, has become so popular that the state is moving to a lottery system for the next round of approvals in January.

“There’s a threshold where economics will make it worthwhile,” said Evan Carlson of IPS. “We’re unlikely to move forward if we don’t get the energy credits.”

‘So much growth’

St. Louis-based Straight Up Solar is also pinning its hopes on the Illinois energy lottery. The company contracted with 12 farms in Illinois, for projects sized from one to two megawatts each. The larger ones will have as many as 8,000 panels. This is new territory for the company, as it has mostly done smaller installations of up to 400 panels.

“To date, the market in Missouri has been primarily small commercial and residential because of caps on what you can connect to the grid. In Illinois, the legislation is just now hitting,” said Erin Noble, director of business operations at Straight Up Solar. “That’s why we’re seeing so much growth.”

The solar industry in Missouri is actually larger than in Illinois, producing a total of 167 megawatts versus 90 in Illinois. But experts say that Illinois, ranked 34th nationwide in solar capacity, is poised to grow to 1,856 megawatts in the next five years, putting the state in 11th place and well on its way to meeting the legislation’s goal to get to 3,000 megawatts by 2030.

Missouri, on the other hand, is only predicted to grow to 214 megawatts over the next five years. The state currently ranks 29th in the country for solar capacity.

“Illinois has deregulated the way they make and transmit power so it’s competitive,” said James Owen of Renew Missouri, a lobbying group working to advance renewable energy and energy efficiency. “In Missouri, all aspects are regulated, so utilities have more of a monopoly.”

Owen said the utilities are starting to move toward having solar as part of their portfolio. The price of wind and solar is making it easier, but Missouri “has no real incentives.”

“Our laws don’t make it easy to finance, to use solar, to have it as an option. The laws could be much better in Missouri,” Owen said.

Noble, who is a board member of both Renew Missouri and the Missouri Solar Energy Industries Association, said the industry has been working hard to improve the state’s solar policies.

Current laws “are limiting Missouri’s ability to expand solar, and limiting job growth,” she said.

Noble added that Missouri prohibits financing to lease solar-energy systems, which also stifles industry growth. “There are smart solar policies that other states have, and we can learn from them,” she said.

Cheaper Solar Prices

Besides the environmental benefits that renewable energy brings, proponents say that switching to solar makes good economic sense. The cost of electricity from solar panels is now lower than the cost of retail electricity for most people, and equipment prices have fallen drastically.

“We’ve seen solar panel prices come down 95 percent. It’s changing the landscape quickly,” said Eric Pasi of IPS, which has been in business for 28 years.

“Renewables used to be expensive but now they’re affordable,” said Peter Gray, spokesperson for the Illinois Solar Energy Association. “Solar and wind are now cheaper than fossil fuels in most parts of the country.”

As a cost-saving measure, a lot of community colleges and universities are looking to build solar, Gray said. “They know they’ll be there, in that location, a long time. The economics work out. They are using rooftops or an open piece of land — all are on the grid but the power they’re producing goes first to their own use.”

Solar Jobs

In 2016, the National Solar Jobs Census found that there 260,000 new jobs in solar were added nationwide. This was twice the number of added workers in 2012. Missouri and Illinois have seen considerable growth as well.

Renewable energy generation is the third-largest clean energy job sector in Missouri with 2,663 solar jobs last year, according to the Clean Energy Trust and Environmental Entrepreneurs. A report by the two groups shows that 470 jobs were added statewide between 2015 and 2016. Solar energy jobs employ almost three times as many people as do wind energy jobs.

“We’ve grown from 18 to 58 people in the last year and a half, and will get to 70 in next few months,” said Noble, of Straight Up Solar. “That’s pretty reflective of what you’re seeing nationwide. It’s a really cool growth trend. Solar is proliferating faster than cellphones.”

In Illinois, the solar industry employs about 3,570 people. The Future Energy Jobs Act is expected to ramp this number up considerably.

The law, which passed in 2016, requires 4,300 megawatts of new solar and wind power to be built in Illinois by 2030. The state is providing $30 million to create clean energy-related job training programs over the next 12 years in order to support the additional workers that will be needed.

Noble said that a new solar ray is installed every 2.5 minutes in the U.S. “There’s enough solar in the U.S. to power 11 million homes. And that number is anticipated to double in the next five years.”

“There’s so much more that can be done to leverage this huge economic development opportunity,” Noble said.

Solar and wind energy development is set to grow in Brazil over the next 5-10 years, and according to some reports, may account for 8.12 percent and 0.95 percent of the Brazilian electricity usage.

In a recent report by local media outlet O Globo, the cost of solar power equipment is predicted to drop by fifty percent, which in turn will boost the growth of the distribution from the consumers themselves.

According to the World Energy Council’s 2016 report, “Global installed capacity for solar-powered electricity has seen an exponential growth, reaching around 227 GWe at the end of 2015. It produced one percent of all electricity used globally.”

“Germany has led PV capacity installations over last decade and continues as a leader followed by China, Japan, Italy and the United States.” All of Lating American and the Caribbean produced .09 percent in 2015, but Brazil has great potential due to the wide availability of solar resource, and therefor not needing to be centralized.

The Banco Nacional de Desenvolvimento Econômico e Social (BNDES) Energy Superintendent Carla Primavera confirms the growth potential and says that the renewable energy market has attracted great interest from international investors.

BNDES was the first Brazilian bank to issue Green Bonds, bonds backed by wind and solar energy projects. It raised US$1 billion – equivalent to R$3.8 billion – for the sector, but demand was five times higher.

Antonio Bolognesi, of Opperman Engenheria e Consultoria (Opperman Engineering and Consulting) says, “In 2012, there was only one photovoltaic power plant connected to the system. Now we have 40,000 to 50,000 connections. In the next 5 to 10 years, we will reach one million.”

So far there are nearly 600 wind farms and more than 7,000 wind turbines in twelve different states. Demonstrating that solar energy still has an emerging presence and is expected to have a major advancement.

The advancement of solar and wind sources of energy raises discussions about the need to maintain subsidies. Elbia Gannoum, president of the Brazilian Wind Energy Association (ABEEólica), says that wind power will soon be in second place in the electricity grid, surpassing the energy generated by biomass.

In the O Globo report, Já Rodrigo Sauaia, president of the Associação Brasileira de Energia Solar (Brazilian Association of Solar Energy, or ABSolar), calls for the creation of a policy for this energy source, for example in housing programs and government buildings.

He also calls for an industrial policy to manufacture photovoltaic modules in the country. Today, the tax burden for the industry reaches fifty percent, which makes it impossible to compete with the imported product.

It should also be taken into account that even though the conditions for solar PV are favorable, dissemination is restricted due to the high cost and lack of indigenous development.

Elgin is one of 22 communities in the Chicago area that will be participating in the SolSmart program, which should make it easier for residents and businesses to switch to solar power, officials said.

Technical assistance on solar energy development will come from the Metropolitan Mayors Caucus, which has been selected to serve as a SolSmart advisor, a news release from the city said.

“SolSmart provides necessary technical assistance to help us improve our permitting processes at the local level,” Mayor David Kaptain said. “This makes solar more easily accessible to homeowners and businesses, and makes our community more attractive to potential new businesses and residents.”

SolSmart is funded by the U.S. Department of Energy Solar Energy Technologies Office and led by The Solar Foundation and the International City/County Management Association, according to the release.

It provides communities a template for a standard installation permit for solar power equipment that’s aligned with national standards, codes and best practices, the release said.

The caucus will consult with Elgin and the other towns on ways to speed up local solar development. Through the program, the communities will have access to resources from the International Brotherhood of Electrical Workers Local 134 and the Illinois Fire Inspectors Association, which can help train staff to evaluate and inspect solar installations, the release said.

Towns also will receive guidance on adapting zoning codes to remove barriers to solar development and engaging and educating local residents and businesses on the advantages of using solar energy.

Volvo is working on Europe’s first energy warehouse that gives electric bus batteries a new lease of life as solar energy storage.

Old batteries from electric buses in Sweden are being given a new use as solar energy storage.

Volvo first introduced electric buses to Gothenburg in 2015 along its route 55.

Disused batteries from these buses will now be repurposed as energy storage for apartment blocks that are fitted with solar panels.

Tenants of the Viva housing cooperative – one of the city’s sustainable housing initiatives – will be the first to benefit.

The battery warehouse, which consists of 14 used lithium-ion electric bus batteries, can store up to 200 kilowatt-hours (kWh) of energy that can be saved for peaks in energy consumption or sold back to the grid.

Ylva Olofsson, project coordinator at Volvo, said: “We know that electric bus batteries have good potential for other applications such as energy storage after the end of their life in public transport.

“What we are examining here is exactly how good that potential is.

“Use of the batteries in an energy warehouse gives them an extended service life which in turn means better resource utilisation and less environmental impact.”

Why solar energy storage is needed

Energy storage is currently a major stumbling block in the transition from fossil fuels to renewables.

The output of coal and gas-powered generators can be easily regulated to bring more power to the grid during peak times.

In contrast, renewable energy sources are dependent on factors that are out of human control, such as wind or solar energy, so are not always able to increase their output of electricity to match demand.

The project was supported by the EU project IRIS, which aims to research innovative green energy solutions, modern mobility and tech innovation within five “lighthouse cities” across Europe.

Volvo is not the first car manufacturer to venture into the solar power market, with Nissan and Tesla both developing their own solar energy storage solution for homes.

MIT engineers have come up with a conceptual design for a system to store renewable energy, such as solar and wind power, and deliver that energy back into an electric grid on demand. The system may be designed to power a small city not just when the sun is up or the wind is high, but around the clock.

The new design stores heat generated by excess electricity from solar or wind power in large tanks of white-hot molten silicon, and then converts the light from the glowing metal back into electricity when it’s needed. The researchers estimate that such a system would be vastly more affordable than lithium-ion batteries, which have been proposed as a viable, though expensive, method to store renewable energy. They also estimate that the system would cost about half as much as pumped hydroelectric storage — the cheapest form of grid-scale energy storage to date.

“Even if we wanted to run the grid on renewables right now we couldn’t, because you’d need fossil-fueled turbines to make up for the fact that the renewable supply cannot be dispatched on demand,” says Asegun Henry, the Robert N. Noyce Career Development Associate Professor in the Department of Mechanical Engineering. “We’re developing a new technology that, if successful, would solve this most important and critical problem in energy and climate change, namely, the storage problem.”

Henry and his colleagues have published their design today in the journal Energy and Environmental Science.

Record Temperatures

The new storage system stems from a project in which the researchers looked for ways to increase the efficiency of a form of renewable energy known as concentrated solar power. Unlike conventional solar plants that use solar panels to convert light directly into electricity, concentrated solar power requires vast fields of huge mirrors that concentrate sunlight onto a central tower, where the light is converted into heat that is eventually turned into electricity.

“The reason that technology is interesting is, once you do this process of focusing the light to get heat, you can store heat much more cheaply than you can store electricity,” Henry notes.

Concentrated solar plants store solar heat in large tanks filled with molten salt, which is heated to high temperatures of about 1,000 degrees Fahrenheit. When electricity is needed, the hot salt is pumped through a heat exchanger, which transfers the salt’s heat into steam. A turbine then turns that steam into electricity.

“This technology has been around for a while, but the thinking has been that its cost will never get low enough to compete with natural gas,” Henry says. “So there was a push to operate at much higher temperatures, so you could use a more efficient heat engine and get the cost down.”

However, if operators were to heat the salt much beyond current temperatures, the salt would corrode the stainless steel tanks in which it’s stored. So Henry’s team looked for a medium other than salt that might store heat at much higher temperatures. They initially proposed a liquid metal and eventually settled on silicon — the most abundant metal on Earth, which can withstand incredibly high temperatures of over 4,000 degrees Fahrenheit.

Last year, the team developed a pump that could withstand such blistering heat, and could conceivably pump liquid silicon through a renewable storage system. The pump has the highest heat tolerance on record — a feat that is noted in “The Guiness Book of World Records.” Since that development, the team has been designing an energy storage system that could incorporate such a high-temperature pump.

“Sun in a box”

Now, the researchers have outlined their concept for a new renewable energy storage system, which they call TEGS-MPV, for Thermal Energy Grid Storage-Multi-Junction Photovoltaics. Instead of using fields of mirrors and a central tower to concentrate heat, they propose converting electricity generated by any renewable source, such as sunlight or wind, into thermal energy, via joule heating — a process by which an electric current passes through a heating element.

The system could be paired with existing renewable energy systems, such as solar cells, to capture excess electricity during the day and store it for later use. Consider, for instance, a small town in Arizona that gets a portion of its electricity from a solar plant.

“Say everybody’s going home from work, turning on their air conditioners, and the sun is going down, but it’s still hot,” Henry says. “At that point, the photovoltaics are not going to have much output, so you’d have to have stored some of the energy from earlier in the day, like when the sun was at noon. That excess electricity could be routed to the storage system we’ve invented here.”

The system would consist of a large, heavily insulated, 10-meter-wide tank made from graphite and filled with liquid silicon, kept at a “cold” temperature of almost 3,500 degrees Fahrenheit. A bank of tubes, exposed to heating elements, then connects this cold tank to a second, “hot” tank. When electricity from the town’s solar cells comes into the system, this energy is converted to heat in the heating elements. Meanwhile, liquid silicon is pumped out of the cold tank and further heats up as it passes through the bank of tubes exposed to the heating elements, and into the hot tank, where the thermal energy is now stored at a much higher temperature of about 4,300 F.

When electricity is needed, say, after the sun has set, the hot liquid silicon — so hot that it’s glowing white — is pumped through an array of tubes that emit that light. Specialized solar cells, known as multijunction photovoltaics, then turn that light into electricity, which can be supplied to the town’s grid. The now-cooled silicon can be pumped back into the cold tank until the next round of storage — acting effectively as a large rechargeable battery.

“One of the affectionate names people have started calling our concept, is ‘sun in a box,’ which was coined by my colleague Shannon Yee at Georgia Tech,” Henry says. “It’s basically an extremely intense light source that’s all contained in a box that traps the heat.”

A Storage Key

Henry says the system would require tanks thick and strong enough to insulate the molten liquid within.

“The stuff is glowing white hot on the inside, but what you touch on the outside should be room temperature,” Henry says.

He has proposed that the tanks be made out of graphite. But there are concerns that silicon, at such high temperatures, would react with graphite to produce silicon carbide, which could corrode the tank.

To test this possibility, the team fabricated a miniature graphite tank and filled it with liquid silicon. When the liquid was kept at 3,600 F for about 60 minutes, silicon carbide did form, but instead of corroding the tank, it created a thin, protective liner.

“It sticks to the graphite and forms a protective layer, preventing further reaction,” Henry says. “So you can build this tank out of graphite and it won’t get corroded by the silicon.”

The group also found a way around another challenge: As the system’s tanks would have to be very large, it would be impossible to build them from a single piece of graphite. If they were instead made from multiple pieces, these would have to be sealed in such a way to prevent the molten liquid from leaking out. In their paper, the researchers demonstrated that they could prevent any leaks by screwing pieces of graphite together with carbon fiber bolts and sealing them with grafoil — flexible graphite that acts as a high-temperature sealant.

The researchers estimate that a single storage system could enable a small city of about 100,000 homes to be powered entirely by renewable energy.

“Innovation in energy storage is having a moment right now,” says Addison Stark, associate director for energy innovation at the Bipartisan Policy Center, and staff director for the American Energy Innovation Council. “Energy technologists recognize the imperative to have low-cost, high-efficiency storage options available to balance out nondispatchable generation technologies on the grid. As such, there are many great ideas coming to the fore right now. In this case, the development of a solid-state power block coupled with incredibly high storage temperatures pushes the boundaries of what’s possible.”

Henry emphasizes that the system’s design is geographically unlimited, meaning that it can be sited anywhere, regardless of a location’s landscape. This is in contrast to pumped hydroelectric — currently the cheapest form of energy storage, which requires locations that can accommodate large waterfalls and dams, in order to store energy from falling water.

“This is geographically unlimited, and is cheaper than pumped hydro, which is very exciting,” Henry says. “In theory, this is the linchpin to enabling renewable energy to power the entire grid.”

Model calculations by ETH researchers show that if China fought smog more aggressively, it could massively increase solar power production.

The air in Beijing is often very bad. The city sinks under a brown cover made of exhaust gases from industry, cars and coal fires, which blow a lot of harmful particulate matter, soot, sulfur dioxide and nitrogen oxides into the air.

The dirty air causes massive damage to human health. According to the World Health Organisation (WHO), air pollution contributes to around 1.6 million premature deaths per year in China alone, and over 7 million worldwide. Victims suffer strokes, heart attacks or lung diseases.

China has therefore begun to introduce tough measures to combat air pollution, also as a way to curb CO2 emissions. Among other things, the government has invested heavily in the deployment of emission-free solar power and plans to expand photovoltaic systems even more in the future. But at the moment, air pollution in China is still high, and smog not only damages health but also reduces the solar radiation that reaches the ground. This in turn significantly reduces the power output of existing photovoltaic systems.

Electricity industry benefits from clean air

The solar energy industry would therefore benefit greatly from clean air, as researcher Mercè Labordena and her colleagues from the Climate Policy group at ETH Zurich have shown in a study just published in the journal PLOS ONE.

The researchers calculated that in the year 2040 China could provide 85 to 158 terawatt hours of additional electricity per year with today’s photovoltaic systems and those that will have been built by then. However, this would be possible only if emissions from all sectors – power, transport, industry, households – are completely eliminated. The additional production would be at least one third greater than Switzerland’s current electricity requirements and would generate up to 10.1 billion US dollars more for the Chinese electricity industry from solar power generation.

According to the model, solar radiation would increase by an average of 11 percent nationwide as a result of strict air pollution control measures. This would allow solar cells to generate one tenth more electricity.

However, the potential for growth is not the same in all parts of the country. For example, solar radiation in Beijing would increase by only 8 percent, but in central Chinese provinces such as Chongqing, the rate would be 26 percent.

Good news for investors

Labordena and her colleagues also calculated the cost of introducing best-practice emission standards in all sectors of the economy. The researchers found that revenue from increased photovoltaic generation could cover 13 to 17 percent of the cost of the stringent air pollution control measures necessary to achieve the zero-emission target.

“Our figures could be good news for investors,” she continued. If the air were free of pollution, their investments would pay off more quickly, freeing up money for the further expansion of photovoltaics, she says.

In the near future, the solar investors who could benefit the most from the government applying stringent air pollution control measures are those on the east coast, where solar expansion is growing the fastest.

This leads Labordena to conclude that reducing air pollution in the populous cities on the east coast would not only benefit public health, but also accelerate the transition to renewable energy and the fight against global warming.