Ashburton Intermediate principal Brent Gray with the school's diesel boiler. Photo: Jonathan Leask / Ashburton Guardian
Fossil fuel burners are on the way out, but school principals fear it means their electricity bills will be on the way up. And that means cutting costs elsewhere.
In the shift to cleaner energy use and reducing emissions, schools across the country are phasing out their old boiler heating systems and replacing them with modern electric heat pumps.
In Mid Canterbury, several still rely on boiler heating, but are making the transition.
Ashburton College currently uses a coal-fired boiler to provide its winter heating but that's all about to change as part of the college's $62 million rebuild, principal Ross Preece said.
"Our new centrally controlled system is electric powered with piping throughout the new campus.
"We are worried that our power usage will greatly increase once this comes on stream."
That's because as well as heating in winter, it will allow the college to cool classrooms in the summer months.
"Almost certainly we will have an increased use of electricity in future years where the school can be heated and cooled.
"Our new build does come with brand new insulation and double glazing throughout which will of course improve our energy efficiency."
The college currently spends around $200,000 on electricity and any increase will impact operating budgets, Preece said.
"You get a heat, light and water grant and ask for that to be reviewed but it's never enough.
"Apart from teachers' salaries which are centrally funded, everything else goes into the one pot.
Ashburton Intermediate’s diesel boiler will be decommissioned at the end of the year. Photo: Jonathan Leask / Ashburton Guardian
"If you are paying $200,000 for power and it goes up $10,000, that's $10,000 less you have for computers, toilet rolls, teacher aides.
"As a school, you have to decide your priorities and electricity is right up there."
What the cost difference will be is unknown at this stage but the costs of running both will come to a head over the next two years, he said.
The college's new 32-classroom Rangitata block is scheduled to be ready for the start of term one next year and then work will begin on the yet-to-be-named block two, also 32 classroom spaces, which is scheduled to be completed by the end of 2024.
The coal boiler is scheduled to be decommissioned in 2025.
"Until the second block is completed we will be forced to run dual heating systems.
"The Rangitata block is run by the new system but the remaining blocks will still need to be heated by the boiler."
Ashburton College is the only school in the district with a coal boiler and its transition to cleaner energy is aided by the Ministry of Education (MOE) funded rebuild, and funding from the Coal Boiler Replacement Programme.
Not everyone is as fortunate. Schools that are not subject to rebuilds or have other fossil fuel boilers do not receive any additional support from the ministry to accelerate a transition from fossil fuels to clean energy, Mount Hutt College principal Jack Saxon said.
Mt Hutt College still runs a diesel boiler to heat around 85 percent of the school.
"The school footprint we use the boiler for has been slowly decreasing over the last four years as we transition to air conditioning units across the school.
"Over the last two years, we have had student project groups shaping up a community drive to install solar panels in the school. This drive is scheduled to start in term three.
"The installation of solar would provide a foundation for a significant move to A/C units over the next five years."
The ministry is currently focused on the transition away from coal but is considering widening the scope, infrastructure and digital leader Scott Evans said.
"We're considering undertaking the replacement of a small number of diesel boilers at some schools nationally as a pilot to better understand the costs associated with replacing diesel boilers and inform future planning.
"As part of our commitment to address climate change, we are prioritising investment in areas where we can achieve the most significant carbon reductions, particularly those that remove fossil fuels and reduce energy use in schools."
Two other Mid Canterbury school sites have also made major steps to lower emissions through rebuilds.
Ashburton Intermediate's diesel boiler will be decommissioned at the end of the year, pending the demolition of its two-storey block which houses the boiler, principal Brent Gray said.
"From then on, the school will be heated via heat pump systems which are going in as part of our rebuild work."
Allenton School has completed a transition to heat pumps but its old boiler remains on site, principal Andrew Leverton said.
"It's been disconnected, but currently we have no plans to remove the boiler. This will come at a substantial cost, so for now, it's just sitting there."
Netherby principal Phil Wheeler has finalised plans to replace its existing diesel boiler funded out of the school operational grant.
Netherby needs a further eight heat pumps at a cost of about $30,000 to heat the school classrooms, breakout spaces, and staff room.
The alternative is replacing the diesel burner and tank for $7500 plus installation costs to heat the same area of the school using around 1200 litres of diesel a year, he said.
There would also be a cost to decommission and remove the existing diesel heater.
Ashburton College principal Ross Preece says they currently use a coal-fired boiler to provide its winter heating but that’s all about to change as part of the college’s $62m rebuild. Photo: Jonathan Leask / Ashburton Guardian
Wheeler was "at this point going with the heat pump option" because it offers much more heating and cooling flexibility.
He raised concerns about the actual emissions savings the clean energy transition would have based on how the energy is generated - replacing his fossil fuel boiler for electricity generated by the burning of gas, biomass, or coal elsewhere.
Wheeler has applied twice to a contestable fund for solar panels and has been unsuccessful both times, which is "disappointing given we are a north-facing school that captures so much sunshine".
The same can be said for the intermediate and college rebuilds.
The new blocks at Ashburton College were being wired for the possible addition of solar panels in the future but would be something they have to fund themselves, Preece said.
The installation of solar panels as part of school rebuilds makes sense as a concept - as schools operate in daylight hours so could be almost energy self-sufficient - but it is not a priority for the ministry.
Evans said the high renewable share of electricity generation in New Zealand means that solar panels are not necessarily the most efficient or effective way to achieve this for some schools.
"However, schools may choose to use funding provided to them to support capital upgrades to install solar panels."
Additional one-off capital funding has been made available to schools which they were able to use to install solar Evans said.
"The School Investment Package provided capital funding to every state school to spend on property upgrades and 31 solar projects were undertaken with this funding. "
Through the 2019 government budget, $5m was provided for a Sustainability Contestable Fund to support schools to reduce their environmental impact and improve their operational efficiency.
Through two contestable rounds, 41 solar panel projects were approved, Evans said.
Local Democracy Reporting is Public Interest Journalism funded through NZ On Air.