How much does it cost to keep your house cool during summer?
JOHN NICHOLSON/FAIRFAX NZ
If you’ve had a big power bill lately, you can probably blame the weather.
Contact Energy said Canterbury’s scorching temperatures in December increased power usage by 28 per cent on the previous year.
Nationwide, consumption was 1.3 per cent higher than in 2016.
The dry weather also resulted in thermal generated electricity nearly doubling from November.
So how can you cool your house without heating up your power bill?
The Energy Efficiency and Conservation Authority (EECA) technical adviser Christian Hoerning said the most energy efficient way to limit the cost of your power consumption while cooling your house was to use a combination of methods.
Start off with free options.
He said running your heat pump on cooling mode to beat the heat could cost you up to five times more than using it on fan mode.
Hoerning said cooling your house using a heat pump could cost anywhere between $60 to $120 per month, but switching to fan mode would only cost a fraction of that.
Heat pumps on fan mode cost about 5 cents an hour, but cooling mode costs at least 25c, almost the same as on heat mode.
A pedestal fans cost the same to run as a heat pumps on fan mode, Hoerning said.
“The smartest way is to use your cheap and free options first. That’s opening windows and doors to ventilate the room, closing blinds and curtains wherever the sun is coming through. As it gets warmer then use your fans and heat pumps,” Hoerning said.
Consumer NZ’s technical writer George Block advised steering clear of portable air conditioners as they ended up costing more in the long term, were loud and required windows to be open to let the duct out.
Block said if heat pumps had a dehumidifying setting, then using that setting to cool down would also use less electricity than cooling mode.
Hoerning said setting the thermostat to 22C was another cost-efficient way to use cooling mode, rather than setting it to the lowest temperature.
He said turning the temperature right down would use up more electricity by overcooling.