12 Sep 2013

21 Tongan high schools to get solar power panels

4:59 pm on 12 September 2013

Rotary New Zealand is visiting Tonga to come up with a design plan for 21 high schools to get solar power panels installed over the next five years.

In 2009, New Zealand aid with Rotary NZ and EcoCare Pacific Trust funded a pilot project in which five high schools had panels installed, so that computers could be used in classrooms.

A Rotary volunteer, Greg Husband, says the pilot project was a such a success that solar panels will now be installed in high schools throughout Tonga.

But he told Mary Baines working out how to install solar panels at each school is not without its challenges.

GREG HUSBAND: The schools, for some reason, are often multi-metered, which means the power comes in from several sources with a meter at each source. And because of the way we have to feed solar generation back into the school reticulation system, unless the meters are all amalgamated in some form we end up sometimes not having a roof that's close enough to a meter source that allows us to connect to it - a main meter source. This system they have of just taking power from the nearest pole round the perimeter of the school and feeding it into the system through a meter is very difficult as far as the installation of solar is concerned. We're going to end up up dividing the schools into components, perhaps ones that are relatively simple to do, so that we can find our way with the contractors that we'll use here. Maybe some are logistically difficult because of position or some aspects of their location would come second. Then those that are in the too hard basket because of this multi-meter situation or anything else, would maybe be a third component. But I'm sure they can all get done. The government is probably not that introduced in replacing infrastructure to support a solar system. They'd rather just have the school authorities do any work that's required there and they'll just be installing the panels themselves and the connections to the grid.

MARY BAINES: And this will be rolled out over the next three to five years?

GH: Yes. It has to be approved first. I don't think there's any problem there. The New Zealand government is pretty with what's happened so far. And as long as we don't find any anomalies that will blow out costs too much beyond the amount that's been approved today, we think it should go ahead.

MB: And as part of your trip you're visiting some of the schools. What are you looking for?

GH: We just look at the nature of the buildings, the orientations of the roof, the pitches of the roof, because it's a wee bit critical to how the panels are fitted, and the power usage, really, 'cause it varies from school to school. Some schools have got 100 pupils and some have got 700 or 800, so there's probably, even though with the pilot programme they just fitted 8-kilowatt systems to each school, I think in this case we'll suggest they size the system to suit the role or suit the power requirements or something like that which we haven't confirmed yet. We're not sure how we'll model it, but we'll work that out over the next month or so.

MB: What kind of feedback have you had from the schools?

GH: We don't really know the feedback, except for the feedback that we've heard from other sources, including Tonga Power. Tonga Power were a wee bit guarded because they were originally willing to have the power exported back into their grid and pay 50 cents, approximately half the price, in other words what they would normally charge, except for the diesel cost. But they're now saying that they don't wish to do that. They'll just take the power back for nothing. We would like a system in place where we'd have the panels maintained. It would make sense for Tonga Power to do that. And we can perhaps put some extra (Indistinct) there so they get a bit of free power and we get a bit of free maintenance, but that all has to be discussed with Tonga Power. They've got to look after their own investment here and they're a bit concerned also that if they've not got solar power in, they might end up running their own system here at less than 50%, which it won't handle, so they've always got that in the back of their minds, that solar power might be a great thing from a carbon footprint point of view. But it does create problems for them.