By Jan TenBruggencate
Advertiser Columnist

Solar photovoltaics — systems that make electricity out of sunlight — still make up a negligible fraction of Hawai'i's power. But here and around the world, solar power is growing fast.

And new technologies promise to provide solar panels at one-third or less of today's costs. That could create a big demand in the industry, with solar power potentially available at costs comparable to or lower than utility-produced power.

Global shipments of solar panels reached 400 megawatts in 2001, double the number just a couple of years earlier. And that's despite not much price incentive. The U.S. Department of Energy figured the price of a photovoltaic module dropped 1 percent from 2000 to 2001, from $3.46 to $3.42 per watt.

But the industry is changing. Residential users became bigger buyers of solar systems than industry, for the first time in 2001.

And there are new technologies that promise to change the numbers dramatically.

Silicon crystals remain the most efficient producers of power, meaning they produce the most power in the smallest space. But they're expensive to manufacture.

Other technologies promise to be so much cheaper that they'll overwhelm silicon-based systems in all but the most space-critical applications.

Konarka Technologies of Lowell, Mass., is using a Swiss technique to develop lightweight plastic sheets coated with titanium dioxide crystals. The material produces power in sunlight and artificial light. The Army thinks enough of the technology that it has invested in it in hopes of developing a lightweight power source for soldiers in the field. The company figures to be on the market late next year with products costing about $2 per watt.

The Palo Alto, Calif., firm Nanosys is working with the Japanese firm Matsushita Electric Works on a technology that can produce photovoltaic cells on flexible materials at very low cost. However, right now they aren't very efficient and they don't last very long. The companies are conducting research to solve both problems, and suggest they could have cells available commercially in 2006 or 2007 at as little as $1 a watt.

Other sources suggest those numbers are more hopeful than realistic, but that dramatic reductions in costs could come by 2010.

Some folks argue that even at today's prices, with solar tax credits now in place, solar power makes economic sense, although there's still a substantial up-front cost. But in six or seven years, it might be possible to coat your roof or your driveway with a compound that will power your home at a price difficult to turn down.

Jan TenBruggencate is The Advertiser's Kauai bureau chief and its science and environment writer. You can call him at (808) 245-3074 or e-mail jant@honoluluadvertiser.com.