Today's Power Trip, Heat Pump & Solar Electric
Visited a double wide manufactured home today. This is a home with about 1500 sq ft, 5 people, one dog, electric furnace with a heat pump and solar electric panels on a tracker in the yard. Heating ducts were tested for leakage and showed about 200 cfm total leakage.
Their power bill for February, 2010, was $220. The bill for the previous month, January, was $160. The homeowner was concerned about the high power bills and concerned about the month of February being higher than January. To me, any electric power bill over $100 is a high power bill. Their power usage does seem high especially when you consider that they have a heat pump ( 14 SEER ) and they have solar electric panels contributing power to the cause.
For this house, the main power using appliance may be the hot water heater. Considering the fact that three of the people in the house are teenagers, it probably is a safe bet.
I was feeling like the heat pump and solar array had not helped this house save power and save money until I checked the power bill and compared the current usage with the usage a year ago – a year earlier, the power bill was $330.
Couple things need to be checked and accounted for. 1. The power bill needs to be read in kilowatt hours instead of dollars and cents. To really get a handle on power usage, concentrate on the kilowatt hours used instead of the dollars owed. 2. It’s winter right now and the solar array will produce more during the sunny skies of summer. 3. The total heating duct leakage is 200 cfm – it would be nice to know what the leakage is to the outside of the home. Further testing is needed. Duct leakage would be good if the cfm leakage to the outside was 100 cfm or less. 4. The heat pump and furnace system should be checked to make sure the heat pump is doing the work and the furnace is not using the heating strips. 5. With teenagers and hot water usage, the flow at the shower nozzle and the flow at the sink faucets should be calibrated. Flow greater than 1.6 gallons a minute is not needed. 6. The refrigerator, clothes washer, and clothes dryer need to be considered for energy factor rating. Plus, the dryer needs to have it’s vent checked and cleaned and the refrigerator needs to have it’s back side cleaned.
I plan to visit this home again and take a closer look at a power bill. I love those little line graphs that compare monthly power usage. I will report back on this home, I can’t wait for summer sun and see what the solar tracker will do.