Most people know, I hope, that the heaviest user of energy in our homes is heating and air conditioning.
I thought you might be interested in how we keep down our use of energy in this sphere. As the A/C part of the "problem" is at hand I will start there.
We have set the time to start using our A/C as June 1st. So we don't start using our A/C until at least June 1st. If the weather co-operates it could be later. It is usually no problem to do this, rarely is it really hot before then and we find by opening windows - with the screens on - and wearing light clothing we have no problem, we might eat salads instead of a hot meal and pull curtains across if the sun is shining in and heating up the house. Eventually, in any year it will get to a point where the A/C is pretty much a necessity. (Here I must tell you of one year back in the late 70's or early 80's when we were here at The Lake in our little redwood cabin on July 4th with our friends John and Norma Hergenroeder and it was so cold that we lit up the wood stove!) That is a true story. So it is not always so hot in the summer!
Anyway the heat eventually arrives and we turn on the A/C and set it at . . . . drum roll here . . . . 80 degrees! Yep 80. Most people will no doubt find this completely unacceptable, but it is just fine with us. If we have guests coming we will turn it down to 78. It might be of interest to know that your electric use drops by 7% for every degree that you set the thermostat up. (Or down in the winter.) So if you normally set your A/C at 65 you will be using about 100% more electric than me! In other words if my bill is $10 a day for A/C yours would be $20 a day. Quite a savings. Some people do have their A/C set at 65 - I've seen it with my own eyes. Most set it at 68, some "frugal" people at 70. Another interesting little fact is that if it gets hotter people will turn their A/C down to a LOWER setting! "Ooh it is 90 degrees today turn the A/C down"! If you have it set at 70 because that is where you like it, it will be 70 in your house if it is 75 outside or 90 or 100, it is not necessary to turn it down even lower. In fact even before we came up with 80 as "our setting" and were using 72 or whatever, if it got really hot I would turn the temperature setting UP. Hey if it is 95 outside, 80 or even 85 is going to feel nice. If you set the thermostat say 10 degrees lower than outside it is always going to feel comfortable, certainly more comfortable than outside, because the A/C removes the humidity which is what makes heat so uncomfortable. And don't forget the 7% rule. If it is hotter, your cost goes UP by 7% for every degree warmer that it is. So if you turn your A/C colder by 5 degrees you are adding 35% to your electric cooling bill PLUS whatever is added by the hotter temperature of the day. To sum that up - if the temp outside is 85 and it goes up 90 - and we are both set at 75, you turn your thermostat down to 70. I turn mine up to 80. Your bill goes up by 70%, mine stays the same! No increase. (I was 10 degrees away from the outside temp - 75 to 85. I am now still 10 degrees away - 80 to 90. But you were 10 degrees away - 75 to 85, but are now 20 degrees away - 70 to 90. So the additional 10 degree difference in your setting is 10, or 10 times 7% equals 70% higher cost.
In the winter we try to wait as long as possible before turning on the heat. (Another little story here, some friends on Gibson Island had the same "game" and one year boasted that they managed to put off turning on the heat "Almost until Christmas."!) When we do turn it on it is usually to 68 degrees. We keep it this "hot" because Julia has arthritis problems and feels the cold. 68 degrees is too cold for most people, but we temper that by wearing warm clothes, long pants and a sweater. Julia will put a blanket over her legs while sitting watching TV in the evenings. It is a lot cheaper to put on a sweater than to turn the heat up. At 72 you are spending 28% more than I am at 68. If you like 75 your bill is 49% more than mine!
As It happens we recently, last winter, installed a wood stove, so our house, especially the living room, where we spend most of our time, is very warm and cozy and the heat rarely comes on at all, we set it at 65 or 62 - it will only come on if the fire dies down and the temp drops below 65 or 62 degrees. This might happen at night, when we are cozy in our bed with a nice warm over sized Duvet on the bed.
Can you imagine the drop in oil use by the US if everyone did this? We would probably have to cut our oil imports by a huge percentage! What would that do to our balance of payments?