How Much Does it Take to Overload the Average Solar System?
Many homeowners are accustomed to seeing their electric meter spinning forward, measuring the energy a home is consuming at any given moment. Scott Gordon is more used to seeing his meter spin backward, counting the watts being sold back to the electric company, and putting money into his pocket.
Gordon is Vice President of Residential Sales for HelioPower, Inc., an energy solution company that has installed over 2,000 solar and clean energy systems. Since Gordon installed a solar panel system on his own Laguna Niguel home in 2006, he has seen his meter spin backward to the tune of $10,000 in savings. With the help of colleague Bret Pursuit, Gordon recently illustrated the savings in the video “Solar Overload, How Many Appliances Does it Take to Spin the Meter Forward?”
The video (if you’re having any trouble watching it or just prefer text) begins with Gordon turning on every light – that’s 56 light bulbs – in his 2,200-square-foot home. Also operating were an attic fan and five ceiling fans, two refrigerators, two DVRs, one laptop and monitor, and one cell phone charger. Pursuit stood near the meter and reported the result: the meter was still spinning backward, sending energy back to the grid.
Turning on the microwave finally caused the meter to spin forward. Gordon pointed out that many consumers don’t realize which appliances – like microwaves – are costing them the most money. Gordon’s pump for the swimming pool at his home also caused the meter to spin forward. Pool pumps typically operate at 600 to 700 kilowatts an hour. Gordon’s electric clothes dryer was another energy-eater, but the energy-efficient washing machine was not.
Gordon then demonstrated a more typical daily energy usage. Since it was a sunny afternoon, leaving the pool pump running, Gordon turned off all the lights. According to the U.S. Energy Information Administration (EIA), lighting accounts for 14% of residential energy consumption. Gordon then turned on a television with a surround sound system. The meter immediately began to spin backward again. In fact, during the short demonstration, the system sent 1 kilowatt of power back into the grid.
Scott Gordon’s 4-kilowatt-sized solar panel system is fairly typical of residential solar systems. Each kilowatt of power can produce 150 to 250 kilowatt-hours of energy per month. According to the EIA, in 2009, the average electrical consumption for residential use was 908 kilowatt hours per month. Gordon says homes with solar power can expect to see meters spinning backward during the day.
Gordon also emphasized that consumers waiting for further advances in solar technology may be missing the boat, pointing out that his own solar panels are five years old, still operating efficiently, and have saved him $10,000 over a five-year period.
“Had I waited for the latest and greatest technology to come out, I would have left that $10,000 on the table,” Gordon said.
Brittany Mauriss is editor for CalFinder, a free service that connects you with licensed solar contractors and general remodeling contractors. Her passions are art, sustainable building, and helping people make beautiful homes.