A solar revolution?

Amidst the depressing news of war, global warming, nuclear proliferation, and the possible literary execution of Harry Potter, there is a glimmer of hope. No, not Rush Limbaugh’s arrest for possession of unauthorized Viagra. I’m talking about the possible transformation of the solar industry, and by necessity, the electric utility industry.

A friend in San Francisco forwarded me an article about the solar startup Nanosolar. The company has developed a method of making photovoltaic (PV) cells by printing them roll-to-roll, like a newspaper. To understand the significance of this, here’s a little primer on the technology.

The modern photovoltaic cell was invented at Bell Labs back in the mid fifties. The technology has stayed basically the same ever since. The manufacturer grows a single crystal of highly purified silicon and slices it into thin wafers. The wafers get “doped,” or infused with slight impurities. The junction between the layers in a wafer, when exposed to sunlight, act as an electron pump, moving the electrons out through a grid of wires applied to the surface. Voila, electricity from the sun. Manufacturers have improved the process, growing thin wafers instead of slicing them, growing multicrystalline wafers, and even applying a microthin layer of doped silicon to rolls of stainless steel sheet metal. It’s still purified silicon, and it still requires lots of energy, high heat, a vacuum chamber, and a precisely controlled environment. That is what makes the things so expensive, between $4 and $6 per watt retail.

The researchers at Nanosolar have used a newer chemistry, Copper Indium Gallium Diselenide, which doesn’t need any purified silicon. Their new process doesn’t need all that high heat and vacuum. It is a thin film process, so it doesn’t use much copper, indium, gallium, or selenium, either. They can print out PV cells by the yard on thin foil. They claim to be able to make PV modules for a fifth the cost of present technology. Their heavy hitting worldwide investors enhance the believability factor.

So what does this mean for you? It means that the cost of a PV system could drop by 40% That’s a better discount than any of the PV rebate programs out there. A good average price for a utility tied PV system is around $8 a watt. A 2,000 watt system would set you back $16k. Around New England you might get around 2,550 kilowatt-hours a year, or 7 kWh a day from this. A 20 year system life would work out to 51,000 kWh total. Divide that back through and you get an average lifetime electricity cost of $0.31 per kWh. Not thrilling. But, knock the Nanosolar 40% off and you get $0.19 per kWh. Add the new 30% federal tax credit and you are buying your solar electricity at $0.13 a kWh. Friends of mine pay more than that right now, and ten years hence we will all be as nostalgic about that price as we are for $1.50 a gallon at the pump. In short, it will be stupid not to install as much PV as you need to meet your personal demand.

A PV boom like this will have a number of effects. First, it will be license-the-technology-or-die for all the silicon-based PV companies out there. Second, it will halt a lot of investment in new conventional power plants and electrical transmission infrastructure. Hey, if people are making it at home…. Third, it will require some rethinking of the way power companies and regulators run our regional electrical grids. The present paradigm is huge centralized plants that produce power on demand 24-7, with scheduled yearly breaks for maintenance. In a Nanosolar America, a larger and larger percentage of the electricity going into the regional power pools will come from individual customers and vary according to daylight hours and local weather. Handling this will take some regulatory changes and technical innovation. Also, the increased demand for PV modules will increase the production of the electronics that connect them to the utility. Suppliers will multiply, production will ramp up, and costs will drop for that technology as well. This is the break that renewable energy advocates have been waiting for.

Cheap PV panels on millions of roofs would mean a significant reduction in greenhouse gas emissions, acid rain, and atmospheric mercury. It could end mountaintop removal coal mining in the Appalachians. The nuclear industry would look even more like a dumb idea. We’d need fewer of those huge power lines marching across the countryside. Finally, it would move us closer to that inevitable transition from non-renewable to renewable energy.

Smile – the future looks sunny.