A New Concentration for U.S. Commercial-scale Solar Power

 

by Jesse Broehl, Editor, RenewableEnergyAccess.com

September 30, 2005 The IAUS's CSP project will begin with a hundred 30-foot modules, like the one pictured here, which all work together to generate power from the sun to drive special turbines. Photo: IAUS

The new 30 percent federal investment tax credit (effective next year) will take the financial sting out of large investments in solar that might otherwise be a riskier venture without it. And the companies making these new commercial-scale investments are charting a new course for solar energy in the U.S.

Traditional solar photovoltaic (PV) technologies, while well suited for residential homes and businesses, are simply not the most efficient way to address commercial solar-generated power. Although you might hear differently from any company sending solar PV panels to Germany where the government incentives are generous, the costly silicon raw material required for PV modules is too precious and in too constrained a supply to be used in large quantities for commercial power plants of multi-MW capacities.

IAUS, like Stirling Energy Systems and Solargenix (see links below to related stories) is pursuing the goal of large-scale solar-generated commercial power through different means.

According to Chris Taylor, a staff engineer for IAUS, the company's CSP power plant will have two fundamental characteristics that distinguish it from regular solar PV technology and other solar approaches. First, it will use a series of a hundred 30 foot-wide modules, each with a honeycomb cluster of fresnel lenses -- effectively stacked pockets of polymer-based magnifying glasses that capture the sun's energy to super-heat water to 1800 degrees F.

In a second stage, the super-heated water is kept pressurized at 3000 PSI to prevent it from turning into steam. This water is then piped into a one of IAUS' patented bladeless turbines -- almost like a fuel in a rocket engine -- where it is released through a narrow nozzle that "flashes" the water into steam that powers an electrical turbine.

Taylor says the company has developed an inexpensive way to manufacture the polymer-based fresnel lenses and, when coupled with their unique rocket-like turbines, the project is likely to eventually expand beyond the initial 1 MW destined for outside Barstow, California.

And it's not just Taylor who feels optimistic about the approach. Power Purchase Agreements (PPAs), a crucial element to a power project's success, are already in the works with utilities in Nevada and Southern California, Taylor told RenewableEnergyAccess.com. He could not say at this time which utilities the company was establishing PPAs with.

IAUS expects to complete construction of the solar power plant during the first quarter 2006. We'll be sure to keep you updated on this and other unique CSP commercial solar applications as they progress.