Schools ‘stoked’ with new boilers
They’re clean, they’re green and, thanks to an EECA pilot project, wood-fired boilers will soon be providing heat to 30 New Zealand schools.
The Renewable Heating for Schools project is helping selected schools to convert or replace existing coal-fired boilers with boilers that are fired by wood pellets or wood chips. The project is expected to cut CO2 emissions by 3,960 tonnes a year.
Schools taking the lead
Among the 30 schools involved is Mairehau High School in Christchurch, which began using its new wood pellet-fired boiler at the beginning of May.
Mairehau is one of several Christchurch schools affected by local clean air legislation which will eventually see the use of coal-fired boilers outlawed because of their high CO2 emissions.
With the help of a $50,000 EECA grant, the school recently converted its old coal-fired boiler to run on wood pellets. It also undertook other energy efficiency measures, including installing new insulated piping, and a computerised system to control heating throughout the school.
Because it was so extensive, the heating upgrade cost more than $400,000. However, according to James Shand, the school’s Finance and Administration Manager, it’s been worth the investment.
“It definitely makes a difference to how efficiently the system works,” he says. “The heat now comes in faster, and it’s more sustained so that the boiler now turns off at about 10 or 10.30 in the morning, instead of about an hour later as it used to.
“The new system has only been going for a few weeks, but we are monitoring its performance and believe it will save us power in the long run.”
There are other advantages too. Mr Shand says it’s good to know that Mairehau High School is doing its bit to help reduce air pollution in Christchurch.
“As a school we want to show leadership in environmental issues.”
Switching to wood pellets also means the boiler now produces 90 per cent less ash than it used to. Even better, the ash it does produce is completely organic.
“We no longer have to get rid of toxic waste from the coal boiler. Instead, we can take the waste straight from the boiler and put it onto the school vegetable garden.”
Pollution conscious
Ferg Harding, the Principal of Menzies College in Southland, is just as happy with his school’s new wood pellet-fired boiler. The new boiler replaced an ageing coal-fired boiler, and was installed with financial help from EECA’s Renewable Heating for Schools project.
“We’re all much more pollution conscious these days, and that’s why we decided to move into wood pellets,” says Mr Harding. “Our Board wanted to show leadership and responsibility in this area.”
So far six schools in the pilot project have either converted or replaced their coal boilers, with work expected to be completed at the remaining 24 schools by the end of July. The project provides grants of up to $50,000 to make the switch.
Worthwhile investment
EECA is monitoring and evaluating the transition. If the project is successful, EECA may look at extending it to include the other 800 schools across the country still using coal-fired boilers.
According to EECA’s Kirk Archibald, wood is a cheaper option for most schools than switching to other fuels such as LPG or diesel. And while wood pellets are a similar price to coal, he says that wood-fired boilers aren’t just better for the environment, they’re much easier to use than those fired by coal.
“They have lower maintenance costs, lower disposal costs and they require less operating time.”
