Sam Jaffe, writing for Slate, has published an article with some well thought out advice on the prospects of going solar at home. His bottom line: "So what do you do if you're a sunny-state homeowner with an urge to go solar and you're being offered an intoxicating subsidy? In the short-term, the most cost-effective choice is probably a solar water heater. Though decidedly low-tech, these systems are eligible for most state subsidy programs and promise to immediately shave 15 percent off most homeowners' energy bills. In a couple of years, when the price of polysilicon comes down and alternative technologies come to market, you can spring for a set of solar panels for your roof. In this case, the worm will go to the bird that waits". Worth reading the whole of Sam's article. Our next question is what to do with our money in the interim? Could invest in the stock of a firm making thin film photovoltaic? Or look for short term gains in the polysilicon business?