When we bought this house, just northeast of San Antonio, TX, there were no blinds on the windows and no ceiling fans upstairs at all. Within a week of moving in, in September no less, we had installed miniblinds on all of the windows and ceiling fans in the playroom and three bedrooms upstairs. With our small improvements, it still got very, very warm upstairs in the summer. I decided that solar screens may be a good investment for the west side of our house that faces the direct, afternoon sun.
We installed no frills solar screens with white frames on the west facing windows on our house, basically the back side of the house. The cost averaged $50 per window.
The comfort of those rooms showed dramatic improvement. The thermostat was located in a room that did not get direct afternoon sun, so I had been cranking up the A/C to compensate for the heat of the rooms baking upstairs. With those rooms no longer heating up, we were able to keep the thermostat at 78 degrees in the summer and be comfortable throughout the house. I do not have any hard data on the savings on our electricity bill, however I can say that we are saving money. We are on a “budget” plan through our local electric company, CPS, where they average our bills throughout the year and then provide us with an average monthly bill. The credit at the end of the first year we had solar screens was 6 weeks worth of electricity, more than the cost of the solar screens, so we more than broke even. This year we had also had a credit, although it was only about $80.
We also keep the A/C fan on circulate in the winter to keep all the hot air from settling upstairs, and then leave the A/C fan on all the time during the summer to keep the air moving. Moving air is not cooler, but creates wind chill across your skin making you feel more comfortable. This keeps our home more comfortable than only having the air moved when the heater or compressor is running.
I have also found that heavier window coverings really help keep the heat in during the winter and keep the heat out during the summer. I just use simple, cheap bed sheets from WalMart to line sheer decorative curtains with two simple sewing seams. I do not hem the bed sheet liners, but instead I trim the sheets to size on two sides, and serge them. These sides to not really show when layered under the decorative curtains. These heavier curtains plus the solar screens have kept the upstairs bedrooms much, much cooler when the afternoon sun hits.