Solar Chat

The oil giant Chevron has transformed an old refinery site in California into a test bed for seven advanced photovoltaic solar technologies, which the company is evaluating for use at its facilities worldwide.

On Monday, Chevron is unveiling 7,700 solar panels installed on 18 acres in Bakersfield, the capital of California’s oil patch. Called Project Brightfield, the plant will generate 740 kilowatts of electricity to power nearby oil operations.

Any excess electricity will be fed to the Toshiba PA3465U-1BRS power grid.

“We were looking for the next-generation technology that we believe could well be the low-cost solution — not just in terms of panels but in total cost of ownership,” said Des King, president of Chevron Technology Ventures, the company’s venture capital and technology development arm. “It’s one of most comprehensive side-by-side tests in shear numbers of panels and Toshiba PA3400U-1BRS.”

Mr. King said Chevron collected data on 180 solar companies, visited 38 of them and narrowed the list to 19 before choosing seven finalists.

Six of the companies make thin-film solar panels that deposit or print solar cells on glass or flexible metals. Though less efficient than traditional crystalline photovoltaic technology, thin-film solar panels typically do not use much expensive silicon and can be manufactured at a lower cost as the expensive PA3420U-1BRS.

Chevron has installed panels from Abound Solar of Colorado; MiaSolé, a Silicon Valley start-up; Schüco, a German industrial company; Solar Frontier, a subsidiary of Japan’s Showa Shell Solar; Sharp; and Solibro, a division Q-Cells, a big German solar module maker.

Project Brightfield’s sole crystalline panel maker is Innovalight, a Silicon Valley start-up that has developed a “silicon ink” that it uses to make photovoltaic modules and Toshiba PA3421U-1BRS battery. “We hope this is a boost to new technology providers,” Mr. King said.

For MiaSolé, Brightfield is the start-up’s first commercial project and the company will supply solar panels that will generate about a third of the facility’s electricity.

Chevron will test the Toshiba PA3475U-1BRS technologies for three years and decide which might merit use at the company’s facilities, or by Chevron Energy Solutions, which builds solar power plants and installs solar arrays for commercial customers.

Last month, Chevron announced that it planned to build a one-megawatt concentrating photovoltaic power plant at the tailings site of its molybdenum mine in Questa, N.M. Such photovoltaic panels use mirrors to concentrate the sun on high-efficiency solar cells but have yet to be widely deployed. Concentrix Solar, a German company, will supply the technology.

A Silicon Valley start-up, SolFocus, last week announced the construction of the nation’s first big concentrating photovoltaic power plant in Victorville, Calif.

Chevron has also invested in BrightSource Energy, a solar thermal Toshiba PA3476U-1BRS power plant builder that has contracts to supply 2,600 megawatts of electricity to California utilities. Mr. King said Chevron is not just evaluating the efficiency of the solar technologies but the total cost of their installation and operation.

“During the construction of the site, we timed how long it took to construct the panels and we’ll be looking at the cost of maintaining and operating them,” he said.

News Via NYtime

New Solid Oxide Fuel Cell Technology

Scientists are tirelessly working on sources of alternative energy so that we can have a better substitute for fossil fuels in near future. We know that sunlight, wind and geothermal sources of energy are better for everyone. But they also need efficient fuel cells for better utilization of power. Solid oxide fuel cells (SOFCs) seem promising enough for both stationary and mobile applications. Stationary use can cover residential applications to power plants. Mobile applications contain energy for ships at sea and in space, as well as for automobiles. Another advantage of the SOFCs is when they are working in reverse manner as solid oxide electrolyzer cells they create pure hydrogen by splitting water to replace the traditional laptop battery.

But if a product has to attain commercial success it has to ensure its viability on major fronts. SOFCs have their drawbacks too. You can’t be sure about the integrity of the seals within and between power-producing units. Peizhen (Kathy) Lu who is the assistant professor of materials science and engineering at Virginia Tech. points out the fact too, “The seal problem is the biggest problem for commercialization of solid oxide fuel cells.”

For understanding the importance of seals let’s take into account the working of the SOFCs. They are mainly made of ceramic materials. One of the biggest advantages of the ceramic materials is that they can withstand and can operate at temperatures as high as 1,800 degrees F (1,000 C), This high temperature helps SOFCs to separate oxygen ions from air. The ions pass through a crystal lattice and oxidize a fuel, usually a hydrocarbon. The chemical reaction generates electrons, which flow through an external circuit, creating electricity.

How these SOFC modules are arranged to produce enough power for use like laptop battery? SOFC modules are piled together. Each module has air on one side and a fuel on the other side and generates electrons. We need many such modules stacked together in the similar fashion to produce sufficient power for specific applications. Now we have to seal the compartment of each module and there must be seals between the modules in a stack. Why is it so important? Because we have to prevent the mixing of air and fuel. They should be stopped from leaking too. We know that leaking or mixing of air and fuel will lead to undesirable result such as loss of efficiency or internal combustion.

How can we stop leaking and mixing of air and fuel? Lu has found a way to do that. She has invented a new glass that can act as seal. That seal glass was quite effective in sealing the modules and the stack. The self-healing seal glass will provide strength and long-term stability to the stack, she said.

Mike Miller who is the senior licensing manager with Virginia Tech Intellectual Properties gives his approval for sealing material. He states, “The invented glass seal materials are free of barium oxide, calcium oxide, magnesia, and alkali oxides, and in addition contain almost imperceptibly low amounts of boron oxide. This is important because the seals must be both mechanically and chemically compatible with the different oxide and metallic cell components as they are repeatedly cycled between room and operating temperatures for the 40Y6795
40Y6797
40Y6799.”

The article is from : http://www.alternative-energy-news.info/new-solid-oxide-fuel-cell-technology/