This EcoGeek post addresses a pet topic of mine: if we are going to invest in renewable electricity generation technologies, we should start by coupling the energy-related benefits with other benefits, particularly at this point when renewables are not yet price-competitive.
Solar parking lot canopies are a great example of this idea. I hate parking in exposed lots or on the top of a parking deck, because then the car is overheated and uncomfortable when I return to it; moreover, I then turn it on and crank the air conditioning to attempt to get it comfortable as quickly as possible. Solar canopies can provide both electricity for the facility and shade and protection for the parked cars; they also reduce the “heat island” effect of dark asphalt parking surfaces.
And, as the post notes, as plug-in hybrid electric vehicles proliferate in the mass market, there’s another possible revenue stream: customers can charge their PHEVs from your solar panels … and they may be willing to pay more than your opportunity cost to do so.
These other benefits and possible revenue streams change the benefit-cost calculation on the solar investment, and should be taken into account.