Powering an air conditioner using the sun might sound like an ideal way to lower electricity bills, but a new report has found some solar powered air conditioners cost more to run.
The Department of Environment and Energy tested two types of solar-powered
air conditioning systems in 2016. One category failed testing and was
subsequently removed from sale in Australia.
The two categories tested include solar thermal and solar photovoltaic air
conditioners. Unlike solar photovoltaic (PV) air conditioners, which
convert sunlight captured by a solar array into electricity, thermal
systems use the sun's heat to turn an electric generator.
All three of the solar thermal air conditioners failed to pass the
department's testing. None passed the Greenhouse and Energy Minimum Standards (GEMS)
standard for heating and cooling and, worse yet, all three operated
between 4% and 21% less efficiently with the solar power technology
The report slammed solar thermal boosting as "a marketing gimmick that
offers no improvement in the performance or amenity of the air
"As a result," it continued, "these models can no longer be supplied in the
In 2012 CHOICE tested a solar thermal air conditioner and found that it wasn't any more efficient or better performing.
The photovoltaic air conditioner, by comparison, passed all of the government department's tests,
delivering "significant improvements in efficiency".
But it had its own drawbacks. Using solar energy proved advantageous until
the air conditioner operated at 75% of its solar array's capacity, where it
became 'unstable' and would switch between solar and mains power.
A lot of stored electricity is wasted by PV air conditioners, the report
found. A solar air conditioner will only use the energy it captures when
it's in operation during the daytime. Energy captured would be wasted
otherwise as it can't be used to power different household appliances.
There are two easy things people can do if they want to run a household
more efficiently, says Chris Barnes, head of household at CHOICE.
"Most households will be better off in the long run by buying an efficient
air conditioner with a high star rating.
"But if you want to reduce your electricity consumption further, look at
installing a solar PV array."