What company leads the nation in solar energy unit production?

No disrespect, but the capless solar tax credit extension already passed as part of the bailout bill.

To me, the most compelling case for solar (both water heating and electricity) is on individual homes, as when that is done, it displaces retail energy. If one makes a giant solar power plant, the energy must be sold wholesale, and transmitted to another place.

So to have a solar boom, individual homeowners must be swayed. There is a large initial investment, so solar might not do very well in a down economy. People will be more worried about their next meal than energy efficiency. Also, the initial cost of a solar array is like a car. And if you look at the impact that tight credit has had on car sales, there is another potential problem.

But after all this, if you're looking for long term investments, I think solar will do well. There are few barriers to entry on the installation business - I think it will be hundreds of small businesses that benefit, not one large one, any more than one company dominates roofing or electrical work nationally. AKNS is the one large installation company, but I personally would not invest in them, because of the lack of barriers to entry.

As far as photovoltaic panel makers, the largest ones are in Asia - Sharp, Kyocera, Suntech, Sanyo, Mitsubishi. There are also literally dozens of small fry, who will probably get killed or absorbed in the next year or two. In the USA, there's First Solar (FSLR) of course, which I think is overvalued, Sunpower (SPWRA), same opinion, and other places like Energy Conversion Devices and Evergreen, that I don't know much about.

Solar Power Design Manual : http://solar.eudko.com/?ZjP