I tell my clients that they live in the COST not in the PRICE. 
The COST includes things like taxes but something IN YOUR CONTROL are utility costs. It is a question every Buyer now asks. What are the utility cost for this home? How would you answer??
1- SEAL UP CRACKS- You lose a lot of heat around doors and windows. Leaks can also be found in your attic access, and even around electrical outlets.
2- ADD INSULATION TO THE ATTIC-The National Alliance to Save Energy reports that half of today’s homes are under insulated. There are many government programs to help pay for extra insulation to be added to the attic.
3- SEAL THE DUCTS-The EPA estimates that if you have a forced air heating/ AC system, up to 1/5 of the heat/coolant is lost due to leaks. Have a professional seal all leaks with a duct sealant.
4- INSTALL PROGRAMMABLE THERMOSTATS– They pay for themselves almost immediately.
5- REPLACE OLD WINDOWS– I will tell you that when I replace my triple track windows with thermopane windows, my energy bill was reduced by 30%.
6- REPLACE HOLLOW CORE DOORS– These allow a great loss of heat. Look at especially replacing the door from the garage into the house with a fire resistant, insulated metal or door. Old wooden garage doors are also energy thieves.
7- INSTALL HIGH EFFICIENCY SYSTEMS/APPLIANCES– As you need them make sure that your new boiler, hot water heater, refrigerator, etc. are all of the highest energy efficiency.
8- GET RID OF THE WINDOW AC UNITS- I was amazed how much I saved on my electric bill when I retrofitted my home with Mitsubishi AC/ heat units. The new ones are very efficient right down to zero degrees. I use mine for BOTH heat and AC right up until about Thanksgiving. Call Dean Demague at High Performance Energy Solutions to counsel you on this. 203 297-2529
9- EXPLORE ALTERNATIVE ELECTRIC SUPPLIERS– I save about $15/mo. on my electric bill by using Ambit Energy as my supplier. For those of you who have been sucked in to teaser rates. With Janet Harner (203 778-9155) you have a local account rep. who will manage and reset your account periodically.