I already the know the common sense answer for this. A decrease in temperature difference between the inside of the house and outside of the house means the heat loss is less. Multiply the reduced heat loss by the amount of time the temperature is lower gives a daily (or hourly or whatever) energy savings. I have seen a rule of thumb that for every 1 deg C you drop the thermostat, you get a 2% savings (of course this is over that period of time).
Being an electrical engineer (not a mechanical engineer), I want to know what the calculations are for finding this out. Or a link to a site that explains it would be fine. I have already done an internet search, and came up empty after 30 minutes. There are plenty of sites that have built in calculators, but none that I can find that give you the formulas, and the reasoning behind the formulas. It would be nice to be able to input the insulation R value in the mix, as well as the efficiency of the furnace. Thanks!
2007-03-19 11:04:41 · 3 answers · asked by photoman 1 in Science & Mathematics ➔ Engineering
Consider equivalent terms. The temperature difference inside to outside can be considered as a potential difference or voltage. Heat flow through the walls is current. Insulation R-value is resistance. Power and energy work the same way.
Work out the equations as an electrical system.
2007-03-20 08:54:52 · answer #1 · answered by Warren914 6 · 0⤊ 0⤋
In your search look up "Degree-Days". This is a classic system for estimating both heating and cooling cost for residences. The degree-days are a time weighted measure of the average ambient temperature at given locations and the temperature in the home. "ASHRAE Fundamentals" will most likely have a section on it and on about any other air conditioning and refrigeration basic calculation you may want. You may not find this on the internet, but you may find it in a library.
I do not know what you are trying to accomplish other than to satisfy your curiosity, as some of us do, but generally, you will get the biggest bang for your buck by first improving the insulation in the ceiling/attic and by reducing the solar load through windows during the cooling season.
Be very skeptical about energy claims made by salesmen selling expensive window replacements.
2007-03-19 11:55:42 · answer #2 · answered by Bomba 7 · 0⤊ 0⤋
Get your hands on a good "Heating and Air Conditioning" textbook and you will discover the answers to all of your questions.
Try Amazon.com
2007-03-19 18:29:02 · answer #3 · answered by gatorbait 7 · 0⤊ 0⤋