Outside the Box Solar | Green Energy News

July 14, 2002 – Vol.7 No.16

OUTSIDE THE BOX SOLAR.

If claims by ATS Automation Tooling Systems hold true, a new solar technology introduced by them could lead to significantly less expensive and far more versatile solar power.

The new technology, known as Spheral Solar (tm) Technology (SST) (the new ATS subsidiary for the new technology is Spheral Solar Power) utilizes small silicon spheres embedded in two layers of aluminum. The aluminum acts as both substrate to hold the spheres and as an electrical conductor. Bonded in the electrically conducting foil, one layer within the silicon sphere contacts one layer of aluminum for one side of the needed electrical circuit. The other silicon layer contacts with the second layer of aluminum to complete the circuit. Electric current to flows when photons in sunlight pass through the translucent spheres and knock electrons off the conductive metal substrate.

So what’s so appealing about the technology?

-- Conventional thin-film silicon solar uses a considerable amount of silicon to make solar cells. (Most of this silicon comes from scrap from the computer semi-conductor industry.) According to Spheral Power, this amount ranges from 18-24 tons of silicon per megawatt of solar electric cells produced. At the current stage of development the Spheral technology would use only 9 tons per megawatt, but this could drop to 2 tons with more development.

Spheral Power thinks it can cut the cost of solar power in half with SST.

-- Because the size of the spheres is small (the company doesn’t say how small) and spheres being embedded in a flexible and formable aluminum layer, sheets of the product can be formed over any shape - including curved roofing materials, domes, and perhaps car roofs to create integrated solar chargers. (For a long, slow charge for electric vehicles, or more likely to power accessories.)

-- The company also claims the technology is very light - though it doesn’t elaborate. Low weight could reduce roof loads on buildings.

-- The company also doesn’t say how efficient SST is, but does say that in testing, efficiency is about the same as conventional multicrystalline cells - about 15 percent, plus or minus a few points depending on the product.

The spherical shape should aid in efficiency. Rays from the sun will always strike a portion of each sphere directly as the sun moves in an arc across the sky.

-- SST doesn’t use any toxic metals.

Even if the efficiency doesn’t meet company expectations, but cost reduction does, SST should still prove a viable technology. Efficiency means less as the cost of the technology or the product goes down. (Like fossil fuel powered cars, few care how efficient they are when fuel is cheap.)

The Canadian company is in the early phases of building a 120,000 square foot facility to house an automated production line (An ATS specialty!) for SST. First commercial production should begin in about a year and eventually the factory should be able to produce 20 megawatts per year, enough power for 6000 homes or so. The Canadian Government through its Technology Partnerships Canada (TPC)/ Climate Change Action Fund (CCAF) has provided CDN $29.5 million ($19 million) in funding earmarked to hasten production.

ATS bought the SST technology from the well respected Texas Instruments a few years ago. Visit Spheral Solar Power at http://www.spheralsolar.com/ , TPC at http://tpc.ic.gc.ca/ .