Thursday, January 3, 2008

Industrial Solar Cells and Scientific American

Scientific American has an article out on Solar cell technology this month. I actually found it a bit disappointing. Very much about engineering solutions with the tools at hand and all the problems with distributed power production and transmission over distance that has haunted the electrical industry from its inception.

A lot is made of solar cell arrays and the idea of huge array farms. A good bit of information is that new technology is now raising the efficiency bar to over 10% for field operations from a prior level of around 7%. A lot is also made of using mirrors to heat a working fluid to drive turbines. This is all good classic thinking that was stillborn last time around by the sheer weight of capital costs and obvious transmission losses from the deserts to the customers.

It is still good stuff and will appeal to the large budget boys. It may even make money.

One aspect of all solar systems that I have never seen anyone allude to is the problem of wind blown silica dust abrasion in the deserts. This is not a problem in any less hostile environments but will be a monster in the best locales. Any thing that can strip the finish of a car in a year will wreak even glass in the same time frame.

I would like to see an article that addresses that issue. I would hate to think that all those new shiny solar farms will be turning into a promoter's nightmare in a year or two. Perhaps my years of listening to dream spinners has made me a little too sceptical.

Right now, we can be very selective in our positioning of farms. That will end pretty quickly when it is decided to build out thousands of acres. I only hope that the taxpayer does not get handed the bill.

Recently, Hydro Quebec mothballed a brand new gas plant because their market projections failed to materialize. What were they thinking? They should know their potential market to a percentage point. Which means that studies were commissioned until someone gave them what someone wanted to hear. And now his successors are eating it. And this from a company that has the best power resource that you can imagine.

The main thrust of the article is to show, however implemented, that solar energy is there for the taking and that is can displace all our static energy needs and perhaps a lot of our transportation needs. The engineering fixes described are not very convincing as yet, but this does focus attention on the fact that we have an alternative for a price that is amply sufficient.

If we are using solar shingles in the next decade with an efficiency of 15% at acceptable cost, then that is likely more than good enough. And everyone of us can help make that happen.

1 comment:

Jkirk3279 said...

"One aspect of all solar systems that I have never seen anyone allude to is the problem of wind blown silica dust abrasion in the deserts. This is not a problem in any less hostile environments but will be a monster in the best locales."

Call up Kramer Junction. They're been in business for twenty years and they must know something about it.

I'll tell you what I learned, by accident.

I had tried to chemically strip the paint off some sheet metal and it wasn't going well.

So at that point I decided to go borrow the neighbor's commercial sized sand blaster.

And it didn't work. The paint HAD softened when I tried the stripper.

So when I turned up the sand blaster, the sand just bounced off the soft paint.

If I hadn't tried the chemical process first, the sand would have scoured the paint off, by shattering the hard coat of paint into loose flakes.

But the soft outer layer of paint acted like a sheet of rubber, yielding with the force of the sand's impact and then releasing the sand to scatter on the ground.

I had unknowingly invented a way to protect glass from sand abrasion.

So, the answer is: make your Concentrating Solar Array with nice, bright silver paint.

And apply a sacrificial layer of soft, clear silicone on top of the reflective paint.

The sand will stick in some areas, but putting in an automated cleaning system -- air blasts? -- shouldn't be difficult.