Solar panels could cut schools' power bills by $20m a year

New Zealand's schools could soon sport rooftop solar panels to help tackle climate change - and cut up to $20 million a year off their power bills.

The Labour and Green Parties have said in their governing agreement this week that "solar panels on schools will be investigated" as part of moving electricity to 100 per cent renewable, non-carbon-burning sources by 2035.

Panama Rd School in Mt Wellington, is using charitable funding to install 30 solar panels on its roof this weekend, and will use the $2000 a year it will save off its power bill to buy devices and other learning tools to prepare its decile 1 children for their future.

"We'll put it back into our students' learning," said principal Jane Dold.

Sustainable Electricity Association chairman Brendan Winitana said the country's 2500 schools could cut their power bills by $20 million a year if they all installed solar energy.

"Schools are the perfect place to install solar because they consume all of their energy during the day and can, therefore, maximise the financial benefits," he said.

"If every school in New Zealand were to install a 25 kWp [kilowatt peak] system then the cost would be about $150 million and this is the scale that the Government should be investigating because it makes financial sense.

"A solar system installed on a school in New Zealand would be paid back within seven years, after which time the savings made on the electricity bill could be diverted into better learning opportunities for students."

Panama Rd School is one of 367 schools which are known by the Ministry of Education to be still using coal-fired boilers to heat water for radiators in its classrooms.

Another 363 schools are known to use gas-fired boilers.

Dold said the solar panels would be used to reduce the power bill for lighting and appliances, but the school could not yet afford a new heating system to replace the coal.

Her top priority for any money saved will be replacing computers, some of which are "well past their use-by date".

"We were donated 30 iPads by another primary school in East Auckland who were upgrading their devices," she said.

Another 10 were donated by the 20/20 Trust when the school joined the Computers in Homes scheme, which provides free second-hand computers to parents in low-decile schools if they attend a course to learn how to use them.

Computers in Homes funding ended in June, but this week's Labour/NZ First coalition deal has pledged to restore it.

The school is also part of a new "Family Connect" pilot scheme funded by the Tertiary Education Commission for adults with low educational qualifications.

"We have a computer suite open to the community," Dold said.

"We have the Digital Technologies curriculum coming in next year and we are trying to build our capability."

The school has raised the $19,600 cost of the solar panels from the Maungakiekie-Tāmaki Local Board ($7500), the Mt Wellington Charitable Trust ($5000) and Mercury Energy, the school's electricity supplier.

Ministry of Education infrastructure head Kim Shannon said the ministry knew of more than 130 schools that had already installed solar panels or were installing them. But she said the costs and benefits would vary.

"Costs would depend on the energy prices that the school has agreed to and changes in these over time, the size, type, and placement of the solar array installed, the weather and its effects on placement, and the actions/costs a school may have agreed to cover such as washing the solar panels annually."