Nice points, Louis.
To speak to your question about solar panels and windmills:
I'm not sure about the industrial solar panels, but I know we just bought some for a solar car project we do with our students, and a panel about 2 square feet in size costs about $80 and produces enough energy to make some of the students' cars move at painfully low speeds (I don't know the actual wattage per typical day they generate, but I could find out once school starts). So it would take awhile before you'd get your $80 back, but at today's energy prices you'd probably recoup your investment before the thing died. You just wouldn't get much energy from it at a time - so you'd need a lot of batteries as well, and a traditional energy source to augment it. It would make a dent in your utility bill but certainly not pay for heating or cooling your home.
Like solar panels, windmills are quite costly and have to run a long time maintenance-free to justify the investment. An example: A few years ago a local EPA office decided to install a windmill, for which they were subsidized by a grant. The newspaper journalist reporting this asked them two critical questions: How much would it cost and how much would it lower their electric bill? The answers were that it cost $50,000 and would return $2000 per year. No wonder no one was lining up to buy a non-subsidized version - the thing would have to run 25 years maintenance-free just to pay for itself.
Geothermal pumps are another environmentally friendly technology that is (in my mind) much better than both solar and wind technologies. For one, there is absolutely no adverse environmental impact, and it also addresses the most costly energy sinks of all - heating and cooling. In a new home construction such a system (at around $15,000 for a 1,500 sq-ft home) would probably make good sense even at today's energy prices. I suspect this will become a pretty standard upgrade on new homes in coming years.
Now, government subsidy, while nice for getting technologies off the ground, gets us nowhere in the long run. Eventually any technology has to become self-sustaining economically. But here's the good part: As fossil fuel prices rise, the savings comes faster and faster. If the return on your $50,000 windmill is $2000 in 2005, then it might be $4000 in 2010. But if you wait until 2010 to build it, the cost of building it (using fossil-fuel energy and from oil-based raw materials) jumps to $100,000. So Louis is right - we are wise to invest in these technologies earlier rather than later. Same goes for any technology that lasts a long time after the initial investment (which is why I like geothermal so much - the plastic pipes last a long time).
That said, from an American perspective, any technology that replaces our need for oil is much better than a technology that replaces coal (which is, unfortunately, what all three of the above technologies do). We've got lots of coal in this country but almost no oil. That's why hydrogen cars are so attractive - cars run on oil, but hydrogen can be made by electrolyzing water, and electricity can be made from coal or any of the above technologies. If we rely on coal to make the hydrogen then we still haven't solved the CO2 problem (if CO2 is indeed the global warming culprit), but it's better than being enslaved to Iran.
-Shawn