Air conditioning and saving energy?

Question

I have my thermostat set at 80 which sux as it is. I find it a miserable temperature but want to save some energy but

I really dont see how keeping it at 80 is any better than 75 once the temperature is maintained. Cooling it to 75 from 80 is the same amount of energy to cool from 85 to 80. 5 degree difference either way right? Correct me if im wrong.

But the real question is that I wake up in the morning..with thermostat set to 80 and it is 75 outside. Is it better to turn off the air conditioner till it is hot again or to leave it be. Yesterday it was 75 in the morning so it turned it off. It was 89 or so in here before i decided to turn it back on. Then it ran for a few hours straight catchin up. What is the right thing to do? It seems that utilizing the cool air outside will save money but running the air so much to catch up seems counterproductive as well.

Thanks.

Answer 1

When you're home and using it set the thermostat and leave it. It's designed to maintain the temperature much more efficiently than you can manually.  It turns it on for a few minutes when the temp goes over the temp you set it for so it maintain a temp and never have to overwork. Letting it climb up to 89 to bring it back down 10 degrees does use more power than if it was set at 80 all along. You'll also be much more comfortable if it's constantly 80 than you are having it rise and fall all day long.

Answer 2

If you don't mind random humidity levels, you can avoid the air conditioner almost completely by opening the two windows at night.  Place a window fan in one window to blow air in (where you are sleeping) and one to blow out on a window in a room where you don't mind it a little warm.  Leave all doors between these rooms open...  Set an alarm to get up early to remove the fans and close the windows just as the sun rise begins.  I find that overnight even on the hottest days, I need a warm blanket.

If you will be running air conditioner, it's best to keep it running with windows closed where you are comfortable because BOTH humidity AND temperature is tied to human comfort levels.  I'm sure that 89 is nice (when it's dry) and 75 is nice when there is a little humidity...  See the difficulty here?

As far as energy use, 5 degrees lower when outside air is 10 degrees higher will probably use more energy because most people do not have perfect insulation... if we did, we might also run out of air...  Forgetting to reset the machine costs money too.  If you develop a habit of using outside air to cool overnight, you won't forget.

Answer 3

Purchase an electronic thermostat to have the ac/heat come on just before you wake up, off when you leave for work or school, back on for time you're at home in the evening. You could probably set it to 77 or 78 for a few hours at a time and still save energy and money.

Answer 4

One politician in D.C. want home and car air conditioning out lawed

Answer 5

Set the temperature at a level that is comfortable, and leave it there.  That is what A/C is for...comfort.  It also keeps humidity down.

Use the furnace fan or overhead fans, if you have them, to move the air around.  It will feel cooler.

Answer 6

I live in Florida and I keep windows open and a bedroom fan on in the evening, all night, and during the morning hours.

About 11 or 12ish, it starts to get really warm and I turn on the AC to a reasonable temperature until after dinner.

Answer 7

It depends on your set up, but good building design has an enormous impact.

Look at the difference between an american town appartment - and an old spanish one.

The American one may have a flat roof, thin metal siding with little insulation, be built in an area which is boxed-in, and have expanses of concrete, white walls, and black tarmac.

Compare this to an old Spanish town - Long streets from valley to hillside promote air movement. Pitched tile roofs absorb heat  - but this rises by convection away from the house. Because of the airy attic space - which is in shade, little heat actually gets to the upstairs rooms. The walls are massive. Between day and night the outside temperature change is huge - but indoors, may only vary by 5 degrees due to the high thermal mass. Building surfaces do not reflect infra-red.

Flooring is permeable - allowing groundwater to evaporate - thus cooling the floors by evaporation. Archways and courtyards provide cool shade - and the air for the house is drawn up from these cool areas by stack effect - up stairwells - and out of shuttered windows.

So, to reduce your power consumption, Increase thermal mass in the house - so it will stay cooler for longer. Shade outside windows, and draw your air  over a cool shaded area.

You could achieve this by simply erectind a wooden pergoda - covering it with a dark canvas, and having a deep pool of water - with a fountain playing over sandstone rocks. This will lower the temperature in this area. Add a few plants or thick screens - and duct your cool air from this area into the house.

If you want to get technical, you could build a "cool store" This is where you stick cages of round pebbles in your basement - surounded by wooden boards to make an airtight box. A fan is used at night to draw cold air through the stones and into the house, then turned off as the sun comes up. When the cooling demand is greatest - around 1pm - the fan is put on again - drawing warm air over the stones - this cools it before coming into the house.   As it gets cooler outside, the fan will still be blowing a comfortably warm air well into the night - before starting over again each night.

The fan can even be solar powered for most of the day,and using stored power at night - so is totaly free to run.

If space is limited - fit security grills to at least 2 windows that allow you to leave them open without fear of intruders.

Answer 8

I keep my thermostat at 80, but I have to say that I have the advantage of being home most of the day. I live in CA and it has been in the 90's even over 100 and I have only run my a/c 1 day this week. I open some of my windows over night since it gets down to the 60's and open all my windows to get a great cross ventilation in the morning.

Since most people have to go to work, opening the windows for an hour while you are getting ready for work would help bring the temperature down before you leave. Making sure all the window coverings are closed can help the heat stay out.

I've found that even with a room in the 80's a fan can help it feel much cooler. To answer your question, it doesn't save energy if your a/c has to run at high capacity for hours to bring your house to a comfortable temperature. The best way to see what it is costing you is check your meter, continue doing what you are doing for a week, check your meter again and try the other way for a week. See which week you use less electricity.

Answer 9

sit outside in the shade if you are really concerned!

Air conditioning is just another part of consumer society and it's only this belief that you need it that keeps it there.

I would suggest having it as minimal as you can and using other methods, (waterfalls, white walls, minimal heating products around you.. think P.C.)

However the answer you prob want is start it early in the morning when its cooler so that it has to work less to get optimum temperature and have it stop as soon as you can manage in the afternoon.