The earlier post on whether solar gives the best bang per buck in greening our electricity ran into some opposition, as I expected. Let me consider some of the objections and issues.
As a recap, I put forward that if we are going to use our money and time to attain greener electricity, what matters is how many MWH we take off the "dirty" grid (particularly coal plant output.) I measured various ways to do that, both green generation and conservation (which do the exact same thing in terms of grid offset) and worked out their cost, the MWH they take off the grid and thus the cost per MWH. Solar PV fares poorly. Converting incandescent bulbs to fluorescent in your own home or even other people's homes fares best.
A big part of the blame lies on the fact that crystalline silicon is an expensive way to make solar cells. It is, however, quite common since many PV plants started with technology from semiconductor fabrication.
One frequent objection is that purchasing expensive solar panels today encourages the market for solar panels, and in particular better solar panels. Indeed, panel makers are generally selling all they can make. Many hope that this demand will encourage financing for the companies who will deliver panels at prices that make sense and compete with other green energy.
I call this being "evangelical green." Leading by example, and through encouraging markets. While I understand the logic, I am not sure I accept the argument.