Using solar power to run an air conditioner is one of those head-slapping ideas that seems so incredibly obvious. After all, sunny hot places are where you need cold air, and that's also where a solar panel can really crank out some power.
The main problem is that air conditioners tend to be real electricity hogs, so you would need a huge number of panels to run the whole thing using the sun alone. But there's no rule that says we need to use an all-or-nothing approach.
Korea's LG has figured that out, and just announced a hybrid central-air unit that gets a small part of its power from a top-mounted photovoltaic solar cell. The panel delivers about 70 watts, which LG claims will take down your carbon footprint by about 450 pounds of emissions over 10 years. Not exactly the kind of savings that are going to save the planet, but I'm sure ConEdison here in NYC would be happy if the summer power grid demand could be lowered a few percent using this type of approach.