One of the easiest things that can be done to reduce the environmental impact of your home is to use renewable energy. You could of course buy your own wind turbine or cover the roof with photovoltaics, but those are both quite expensive and may not be appropriate for all homes. However that doesn’t stop you using renewable energy.
You might not be able to make your own, but why not buy it from someone else? Just as you can shop around to buy cheaper electricity you can also shop around for greener electricity. A service like Simply Switch can quickly find you a greener electricity supplier, and depending on who you buy your power from now it won’t necessarily be any more expensive.