For a "green home," do I really need a high-efficiency furnace, appliances and new windows?
It’s better to go low-tech according to Lane Burt, a building-energy expert with the Natural Resource Defense Council. Hire a pro to find all the leaks in your home and plug them up. This should cost much less than a new heating system, so you won’t be heating the outside of your home. The best energy efficiency measure you can take is insulating and air sealing your home, according to McKinsey & Company.
A March 2014 report by the American Council for an Energy Efficient Economy looked at efficiency programs in 20 states from 2009 to 2012 and found an average cost of only 2.8 cents per kilowatt-hour – about one-half to one-third the cost of alternative new electricity resource options.