trying to understand my electric bill?

Question

ok, Im looking to buy a generator to run my house during power outages, my bill said I was using an average of 12.68 KWH/ day, I know thats killowat hours, but how many watts dose that mean Im using at a constant??

Answer 1

Forget what your bill says.
To make things simple, let's say your average usage was 12KWHR/day, this would be an average of 0.5kwhr/per hour or an average load of 0.5kw continuously. 0.5KW is 500 watts, this is the average load over the entire month.

There would be times that you were using only a few watts (when everything is turned off except for small amounts of power used by the VCR and TV sets in standby, cell phone charger, clocks etc etc etc) and times when you might be using a few thousand watts (lights and TV on, furnace blower running, microwave oven, clothes washer etc etc).

The information from the electric company will not help you in choosing a generator unless their meter included a "peak demand" feature (which residential meters do not).

What you need to do is determine how much it will take to run the necessities. Things like the furnace or air conditioner, refrigerator, a water pump if you have a well, and other things that you will want to run when the power is out. The bare minimum for most people will be a 4kw generator. I have a 7kw and it suits me ok except that I cant heat my home with it since I have an electric heat-pump system, everything else runs fine. You also need to have some "overhead" to allow for starting motors, generators will usually be rated with a continuous and peak rating. The refrigerator probably draws about 3 amps when it is running but needs about 30 amps for 1 second to get the compressor running. If the generator wont stand that (along with whatever else may have been running at the time), the voltage will drop too low, the motors will stall and kick out. Better too big than too small.

If you turn on all the things that you would need running at the same time, you can measure how much power you are using at any particular instant in time by measuring how long it takes for the wheel in the kwhr meter to make one revolution. This is how you do it:
On the kwhr meter there will be a plate with the KH value of the meter, maybe something like 7.2 which tells how many watt-hours it takes to make a revolution. Multiply this by 3600 (to convert from hours to seconds) and then divide this by the number of seconds it takes for the wheel to make one revolution, the answer will be the number of watts you are consuming at this moment in time. When sizing the generator, allow for a significant amount of overhead to allow for motor starting.

To legally connect this to your electrical service, you need a transfer switch. There are two common types; one diverts your entire electrical service from the utility company to the generator and the other type wires into your breaker panel and lets you switch some of the circuits over to the generator (important things that you need, not everything). Neither is a cheap proposition.

Answer 2

Start by switching all of you light bulbs to compact fluorescent. Most electric companies offer these for free or at a low cost. Turn down the temp on your water heater and buy an insulating jacket for it. By all means use the toaster oven instead of the range oven. Microwave whenever possible. Invest in a drying rack and dry clothing on it. I dry clothing on the auto cycle to damp dry and finish most items on the rack. It is a bit more work but saves money. In the summer use a clothesline. Put clothes in dryer for 10-15 min to de-wrinkle and finish on the line. If you will be away from the computer for more than 2 hours, shut it off. Unplug small appliances when not in use. If you do not already have drapes, there is another investment that can cut down on heating costs. Many people have the temp on their freezer and fridge set much lower than necessary as well. Start adjusting the furnace thermostat down 1 degree every 3 days until you have it turned down 5 degrees. Wear layers and deal with it! Invest in a humidifier, the moisture in the air makes you much more comfortable at lower temps. If you shave your legs in the shower, use a bowl and turn off the water as you shave. If you make a cake, stir it by hand. Dont use the food processor to chop small amounts. Invest in a couple of lamps instead of lighting the whole room. You can use smaller wattage bulbs in many areas without noticing a huge difference, especially in areas like the bedroom. Don't leave outdoor lights on unless expecting someone. Add a couple of blankets to the bed and turn down the heat at night and if you are gone most of the day. It warm right back up and you do not use more energy getting it back up, that is a myth. You can save in a lot of little ways that really add up, especially this time of year.

Answer 3

You will need to calculate the peak load for appliances you wish to operate from backup power. The electric bill will not give you the information you require.
Read through my home generator page for ideas on what you need, safety ideas, as well as connection requirements.
http://members.rennlist.org/warren/generator.html

Answer 4

You should ask your electric co. about this. If you install a generator they must be notified . It's the law