What to charge for solar installations?

I couldn't afford to go to Harvard (and temporarily ignoring the fact that they wouldn't have accepted me even if I had the money) but I know someone who went to Harvard Business School and he says "Charge as much as the market with bear"!

Jeff, I charge according to time and materials. The easier the installation and the fewer materials the cheaper it gets. I do it this way in order to help promote the technology, since I feel the only way this stuff is going to catch on is for people to see it in action and the only way customers will purchase a system is if they can afford it. I've had customers tell me that they had quotes of up to $15,000 for systems that I can install for $5-6000.   
 Most other companies have a flat rate and tend to install on roofs which can bring the cost way up. Others will sell you only the basic components at high cost. One example is Shu.... Solar. He sends me flyers trying to sell me two SHW panels, an 80 gal. tank with pump and gages and an expansion tank for over $6000 plus shipping. Then you have to purchase everything for the installation separately, pipe etc., somewhere else. This drives material cost way over what I do a complete installation for. Then add labor costs.
 So to answer your question, charge accordingly, keeping the customer and promotion of the technology in mind, keep it simple, and be honest.

Tom, this is the attempt I was trying to go for. I want a somewhat conservative rate, but would like to promote solar technology which is new in the area with low costs and big efficiency and payoff rates. Hasn't hit here in Philadelphia big yet but we have to start somewhere. Some guys a state over in New Jersey told me they were charging 1.75/watt in labor and all permit and extra material costs added. Doesn't sound like a horrible rate. I can assume solar hot water systems are considerably less. I was just looking to get some ballpark rates for these installations so I know whether to go higher or lower depending on the difficulty of the job. Your opinion helped. Thanks.