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Cost of electricity: $.10-.20/kwh, grid.
Grid Tie Solar kit(NOT INSTALLED!): $8,239.97
Assumptions: Cost of Capital 5%, Capacity Factor: 30%, lifespan 40

*Crunches Numbers*... Welp, wasn't expecting this. Last time it didn't work out...

Okay, at $.10/kwh utility rate - I came up with it producing an estimated $604.44 worth of electricity a year. If it's expected to last 40 years, the annual cost should only be $480.21. At that rate, it should pay for itself in 23.5 years(assuming no repairs needed). Not the greatest of investments, but sound for places like business. The duration imposes a large amount of risk, in my mind.

It makes sense at the cheaper rate? What about if you're stuck with expensive electricity, at $.20 a kwh? Well, now it's displacing $1,208.88 worth of electricity, still only 'costs' you $480/year for the loan payment/opportunity cost, and pays for itself in 8.5 years.

Now, this is just a kit, what if you have to pay money to have it propery installed? Let's say, $1/watt. That raises the cost to $10,540, raises the annual cost for the system to $614, but only saves you $604. No longer worth it. Payoff rises to 11.7 years for the expensive electricity option, so still worth it. Now if only I didn't live in an area where I'd be lucky to get .2 with the system... 22 year payoff = tough decision. Still, at this price point I'd expect to see them popping up all over down south.

Disclaimer: This is a off the cuff estimate. Please do the calcs for your specific situation before spending $10-20k on alternative power.

The high cost of polysilicon has been an obstacle to cheap solar cells for years - mostly because polysilicon is commonly produced by the "Siemens process", which is a batch process where silane gas is converted to pure silicon from the heat of tungsten filaments, on which it deposits. Once the filiament is adequately encrusted with polysilicon, the deposits are scraped off and used.

There have been a number of attempts at a continuous process to produce polysilicon. I worked at one, J.C. Schumacher, over 25 years ago. The process never has been scaled up to full commercial production; Dr. Schumacher is still looking for an investor to take him there.

There is at least one other company with a fluidized bed continuous process to make polysilicon.

One approach that I thought that had a good chance of hitting the big time is the spheral solar process that Texas Instruments developed, and sold off in 1995. This process did not require pure silicon to produced chemically. It took 99% pure metallurgical grade silicon beads, heat treated them so that the impurites moved to the surface, then ground off the surface with the impurities to make silicon crystal balls pure enough for solar use.

Any of these processes might be viable if the right market conditions exist. And any of these processes use a heck of a lot less energy than the traditional Siemens process.

I recall reading a another article about mems-based micropower supplies. But in that case, they were designed to turn stray vibrations from the environment into power. The mems-based nuclear battery designs sound awfully similar. I suspect that it would be possible to make a mems device capable of absorbing power from both vibration and particle emission, thereby increasing output and useful lifetime.

Likewise, the diode-type nuclear battery could double as a photovoltaic cell if it was made in the right type. Consider planting a radioisotope seed in the center of the photovoltaic beads that spheral solar's panels use. All particles would be absorbed by the silicon and there would be no need for additional sheilding. Manufacture would be easier than with a conventional flat cell.

In both cases, the devices would derive a good portion of their power from non-nuclear sources, nuclear power alone would provide a constant if reduced stream of power, and as the isotopes wear out the devices continue to function when source power is available. It may have its uses.

Just when Spheral Solar is finally working out the manufacturing angle. Their tech has the advantages of crystal cells but is flexible.

Just when Spheral Solar is finally working out the manufacturing angle. Their tech has the advantages of crystal cells but is flexible.

See this company: http://www.spheralsolar.com/ their technology makes very cheap, very efficient, very flexible solar-cells... they are building a massive manufacturing facitliy as-we-type, they do small(er) runs currently in their original test/research facility.

this is one to watch.

of the demo House

And here is a picture of the material in production

Score:4, Informative???? The first link points to siding which has nothing to do with solar power, or Spheral Solar Power, Inc.. The second link points to a picture of a denim apparel factory in China.

If you want to learn more about the product, go to the company's web site.

Accoding to their website:

A significant breakthrough in renewable energy, Spheral Solar Power cells produce electricity at considerably lower cost than conventional solar technology, and on a cost-par with fossil-fuel based electricity in many regions of the world.

Slashdot has a way of posting news, but no backup information sometimes. Or maybe I am the only one who actually reads the articles.... Here is an overview of the technology. Here is a link to the company making this product, speral solar power. Not much in great detail about the strength of these products, other than "very strong" or "stronger than regular solar cells".

Slashdot has a way of posting news, but no backup information sometimes. Or maybe I am the only one who actually reads the articles.... Here is an overview of the technology. Here is a link to the company making this product, speral solar power. Not much in great detail about the strength of these products, other than "very strong" or "stronger than regular solar cells".