New Hampshire, USA — Sinking revenues and shrinking policy support may be causing a bit of a haze on the renewable energy horizon, but there’s plenty of sunshine trying to peek through if you look hard enough.
There’s no doubt that everything from solar to biofuels are under assault from legislative halls to the comment boards. And while there are still gains being made, they’re not always evident.
As the renewable energy industry faces another tumultuous week with hearings on Capitol Hill, a highly awaiting trade ruling by the Department of Commerce and intense debate across Europe, we thought we’d spend the day wrestling up some of the other developments that could bear fruit once the clouds pass.
Concentrating solar power (CSP) has struggled to keep up with the rapidly falling prices of PV, making the technology a hard sell to investors.
But what if CSP could find cost gains that increased capacity, cut costs and made it more competitive on price with PV? That’s the hopes for 3M’s Renewable Energy Division and Gossamer Space Frames, which have teamed up to design a parabolic trough technology that they say sets a world benchmark for solar concentration and could ultimately reduce the installed cost by 25 percent. The companies say they achieve the new highs in capacity and new lows in costs by combining 3M’s Solar Mirror Film 1100 with the designs of Gossamer Space Frames.
The demonstration facility is fully operational in Daggett, Calif., at the Sunray Energy facility, which is owned and operated by Cogentrix Energy.
The new system, which had its ribbon-cutting ceremony in early April, began operating in October 2011 and provides a peak of approximately 275 kw of electricity. A second project using the system design is underway in a separate location and project commissioning is scheduled for June.
The National Renewable Energy Laboratory (NREL) has verified performance of the system, measuring an optical accuracy of more than 99 percent.
Abandoned Mines and Geothermal Energy
Abandoned mines are costly to monitor and maintain, and a potential danger to surrounding communities. They’re also an untapped source of geothermal energy.
Researchers at McGill University in Canada have investigated a method to determine energy potential when flooding mines with water. This technique has already been used at certain sites in Europe and Canada, but McGill researchers hope to expedite adoption with a model that engineers can use to predict a mine’s geothermal potential.
The process seems to be straightforward: flood a mine with water, allow the water temperature to rise from the naturally hot rock, pump the water to the surface, extract the heat to create steam and ultimately energy, and pump the cool water back into the mine.
According to the researchers, each square kilometer of mine could produce about 150 kW of capacity. Up to one million Canadians could benefit from this method, and the potential rises in more densely populated nations.
“Abandoned mines demand costly perpetual monitoring and remediating,” said Seyed Ali Ghoreishi Madiseh, lead author of the paper at McGill. “Geothermal use of the mine will offset these costs and help the mining industry to become more sustainable.”
Image: Przemek Tokar via Shutterstock
Renewable Energy in Store
Whether it’s for the energy savings or the good PR, Walmart is flexing its buying power. The company has a lofty goal of using 100 percent renewable energy and it’s making headway in a part of the country where solar is only now starting to make some inroads.
Massachusetts Gov. Deval Patrick has set a state goal of 250 MW of solar by 2017. The state currently has 100 MW, up from just 4 MW in 2007. Walmart announced it was adding to that total by installing 10 MW of distributed thin-film PV on rooftops of 27 stores across the state by 2014. The arrays will power 10 to 15 percent of each store’s energy needs, and once it’s done it will be the state’s largest consumer of solar energy. Plus, there will be room for expansion.
It may be a relatively small bump toward the state’s target, but having Walmart in your corner is clearly a good thing. According to the EPA Green Power Partnership program, Walmart is the second-largest onsite clean energy power generator in the country with projects that provide 1.1 billion kilowatt-hours (kWh) annually. That fills about 4 percent of energy needs for Walmart buildings across the globe. As of 2010, the company also received about 18 percent of its energy through renewable sources through the grid. So that leaves a lot of investment, and scores of possibilities like fuel cells, microwind and offsite power purchase agreements between now and that 100 percent goal.
It was perhaps a small milestone on the decade it’d take for completion, but on Monday the Department of the Interior gave the Atlantic Wind Project permission to move ahead with an environmental impact statement for an underwater transmission line that would span 350 miles from Virginia to New Jersey.
Once transmission cable is dropped along the ocean floor, the project would serve as a backbone for an offshore wind industry that so far has struggled to get in the waters off the Atlantic coast.
The project $5.5 billion has some serious high profile backing with Google and Elia, a Belgian-based transmission system operator. It would enable integration of up to 7 GW of offshore wind, and it’d serve some of the major metropolitan areas of the East Coast.
The Atlantic Wind project is among the many major global transmission projects that have been proposed in recent weeks. And many of these projects have a stated goal of linking renewable sources to far away population centers. Iceland has proposed a transmission line along the ocean floor nearly 1,000 miles long that would bring geothermal energy to the U.K., China started building out its transmission superhighway that will bring solar and wind to growing population centers, and longtime rivals India and Pakistan are among the nations in the South Asian Association for Regional Cooperation that are in talks to build out regional transmission lines that would allow power sharing between nations.
A Real Replacement for Coal?
According to an industry analyst, the biomass industry might just have a game changer in black pellets, torrefied wood pellets that are a direct replacement for coal and look strikingly similar to animal droppings. Waterproof, more energy dense than traditional wood pellets and used just like coal, a strong market for them already exists in Europe, where coal plant owners are subjected to carbon penalties.
“Everybody has been waiting for this torrefaction technology to cross that threshold of market viability and so far it hasn’t made sense,” said Bill Strauss of FutureMetrics, who is a consultant on two different black pellet manufacturing plants in development right now.
New England-based Cate Street Capital is currently building a 300,000-ton per year black pellet manufacturing facility in Millinocket, Maine, at a former pulp and paper mill. The company bought the torrefaction technology that it is using from a European developer and Strauss said the technology is admittedly “odd.” Giant microwave ovens torrify the wood, much different than the traditional way torrefied pellets are made, which is through thermal processing of wood in an oxygen-starved environment. “The only reason it makes sense is that they have really cheap electricity,” Strauss explained. When Cate Street purchased the pulp and paper mill, it came with a 105-MW hydropower plant that produces power in the $0.04 per kWh range.
Strauss said that when the facility is complete it would export 100 percent of its black pellets to Europe where low-carbon fuels are in great demand. “As long as the wood starts from a certified sustainably harvested forest, that’s a definite requirement, then you consider it a low-carbon fuel,” he said. “It’s actually zero carbon in combustion.” European utilities get huge carbon mitigation benefits from using this fuel, he said.
On the other side of the country, Seattle-based TSI, which designs and builds equipment for the engineered wood and biomass industries, is also making strides in black pellet manufacturing. Strauss said TSI has had a system in place for a few years but it is now “performing at an economic edge.”
The black pellets cost more than coal but “when you add the carbon penalty to burning pure coal and you offset that with the non-carbon penalty of burning black pellets, it’s actually a good deal for them [utilities in Europe]; they lower their cost of generation,” said Strauss.
Strauss said that even though torrefaction technology has been around for a long time the costs have been too high to make the technology viable. But he believes we are crossing that threshold where “now the cost is equal to the value or maybe better in some cases.”
“In a year from now or so, I would suspect that it’s going to be a game-changer in terms of the whole pellet export business,” he said.