Sustainable energy projects – rewarding for students, schools, and community

David Dobbin: I went and studied technology at Massey University and from there went into heavy industry really, mainly in pulp and paper, as a technologist. After sixteen years in that industry, I went into energy efficiency and so that gave me a good background in solar water heating, photovoltaics, space heating, heat pumps, all of that stuff that leads to reducing energy demand, and cost, the cost of living, and so forth.

So I’ve been a convert now for quite some time, so when I came to Trident High School, that was a natural progression for me to think, “Technology, my background is energy and this is a really current topic out there in the environment, and I could build a year 13 programme that was current and exciting for me and I could share that passion with my kids”.

That caused us to really look at renewable energy and energy efficiency at the school. So in the first year, we focused on solar water heating and the kids researched all the types of solar water heating that is current, so current technologies including evacuated tube systems, flat panel systems, DIY systems that people build for themselves using plastics and coppers and a whole range of materials. In that year the kids focused on flat panels of different construction and took home for themselves a fully functional model that heated a litre of water passively from the sun which they measured efficiency, temperature gain over time, knowing the radiance that’s landing and so forth.

So they made these models and they raced them competitively and then from that, on the ones that were most successful, analysed exactly why they were successful, and then based on that advice, two full-scale systems that, one of which, is still on the roof today, four years later, feeding our solar water heating system and hot water cylinder in the corner over there that they installed.

The next year we got into photovoltaics. So we got into identifying what silicon cells were and imported some from Silicon Valley in the States. The kids had to look at an authentic need at home. For some of them of course, it was powering iPods, for some it was laptops, for some it was cars, for their car chargers, powering a caravan. So they looked at an authentic need that they really had and wanted, and they designed a solution using an array of photovoltaic cells of all differing sizes and number of cells.

Then we raced them competitively too, looking at their briefs they had developed and who was the closest to satisfying that brief in terms of volts, watts, current, temperature gain and all those sorts of things on the panel.

And this year was the most exciting of all. We’ve ended up with four renewable energy technologies that are real and they are installed and they are generating electricity and they stay at school, they become teaching resources. So those systems are in, to their specification and the next step for several of them would be then to refine them further which is part of the project teams this year, to evaluate the performance of these systems and then make recommendations on design refinements for the future. For example, with the microhydro system, having a flow control system with solenoid control. You can even see that a system like that, which has been manually opened, could be integrating with digital technologies, with Arduino programming that could control solenoid valves, that can open actuators and things like that. A lot of that will be decided by the project group, the team, the student group next year in terms of, these will be some options that I see, what options do they see, and we co-construct those project type.

Well I’ve picked up mostly Level 3 technology achievement standards. There’s a safety unit standard, but we’ve also integrated in there an environmental sustainability achievement standard which is about a personal action plan for improving sustainability. We also have, (which we’ve done for two years now) we’ve picked up a physics assessment that our head of physics assesses. It’s a problem to stop them working, not to start them working on these projects.

I think too, that it’s really authentic. Renewable energy is a "now" topic. It’s so prevalent in media that kids know the topic. They study it in science and social sciences and stuff. Here they actually implement, rebuild, test, evaluate those very technologies that are being talked about as being the solutions of the future.

Hamish: Our project for this year was based on the context, which we used to develop a brief, and the context that we had was to get the school’s energy consumption to drop by a certain percentage. And at this stage of the start of our project, it dropped by ...
Marco: Twenty-six percent. The school's overall usage has dropped, and power cost has dropped by 26%.

Hamish: Yep.

Marco: And that’s over three years.

Hamish: Yep. Three years so far.

Marco: And the goal is 40% over five years.

Hamish: And so based on that context, we were given a bunch of renewable energy technologies and with that there was the option of solar water heating, wind turbine, a micro-hydro system, and then lastly was the solar PV panels, which we both choose.

Our deadline was more or less the year eight day for our school. Our principal wanted us to have the solar panels up so that everyone could see them, so that was also incorporated into our consideration for where we would place the PV system because they had to be easily seen, easily noticeable, and also they had to maximise the sun that they could get. So that is why we put them on to the Special Ed Centre building.

Marco: Our goal was the year eight evening – was that we put it in two months before that, three months before that. We did have a lot of help though.

Hamish: Yep.

Marco: So we couldn’t have done this without the technical assistance of Mr Dobbin, Stuart from Ark Electrical, who was the electrician on the day.

Hamish: The main problem was because we wanted to connect to the Special Ed building and we also wanted to have the Special Ed building still connected to the grid in case for whatever reason there wasn't enough power generated. Because of that, we had to look at an application to connect to the lines.

Marco: From Horizon.

Hamish: From Horizon, which because our application was so detailed, it got approved overnight. So because we were working above, it was ...

Marco: Two metres.

Hamish: Two metres. Because we were working above that, which even though the roof didn’t look like it was much of a slope once we got up there, we found out it was. We had to have either harnessing or ...

Marco: A handrail.

Hamish: Handrail.

Marco: Some sort of edge protection.

Marco: So it goes like scaffolding along the guttering.

Hamish: Yep.

Marco: We’ve got that here.

Hamish: Yip, so what we did was we worked with local businesses and we managed to get Davie Painters because they were already working in the school. We worked along side the caretaker and he organised for Davie Painters to just leave their scaffolding up for us so that we could work on the roof and be safe about it.

Marco: We could put all the panels on, run all the cables, everything. Just not go into the switchboard and do that.

Hamish: Yep.

Marco: We just couldn't make the final click. What we needed ...

Hamish: Because that had to be by a certified electrician.

Marco: Out of the contexts for the course it was.

Hamish: Yep.

Marco: It's sustainability through practice and it has to be able to be monitorable. What we had to do was make a website.

Hamish: We had to look at seeing how efficient our system said it was and how efficient our system actually was.

Marco: What it does is it tells us exactly how much we producing, how much we’ve saved, how much it's making right now. It's a continuet, it updates every 10 minutes and it sends emails to the school weekly.

Hamish: Our teacher Mr Dobbin is just so passionate about, cause his house is completely sustainable almost. He has power bills we he gets paid because he sells back.
Marco: To the grid.
Hamish: His extra energy to the grid, so most of his power bills are income for him.
Marco: Because that's the way the world's going. It's going sustainable.

Jacky: So our special education centre has twenty six students, ranging in age from 13 to 21. The renewable energy project has been a great project for our centre to be involved in. We elected two energy champions at the start, so that they could be involved in the process and ask questions about the solar panels and the impact that it might have on our centre. They sat in on all the meetings that we had with Marco and Hamish. And some of the questions that our students had were cost – and would it help run our spa actually – was one of the first questions that they wanted to know, would that save on that cost. They also had questions like if the solar panels were hit by lightning, what effect would that have on the solar panels? They also wanted to know where the inverter would be within the building and were quite concerned that it was placed in a position that some of our more vulnerable students wouldn’t have access to it. They then were charged with presenting back to the rest of the students and staff at the centre.

Marco: Dealing with the children themselves directly would have been a hassle because they’ve got, they’ve got a lot of activities they have to do because they have a very special curriculum over there. So we had to like, consult the teachers ...

Hamish: Yeah, we had to organise meetings and consult with the main teachers and then, that's why Katie and Matthew were identified as the energy champions so that they could be the ones that were taken out and helped us, basically worked together, to produce the final handover.

Marco: For our monitoring ...

Hamish: Yep.

Marco: It's sustainability through practice and it has to be able to be monitorable.

Hamish: Yep.

Marco: So what we had to do was make a website.

Hamish: We had to look at seeing how efficient our system said it was and how efficient our system actually was.

Marco: What it does, is it tells us exactly how much we are producing, how much we’ve saved, how much it's making right now. It's continual, it updates every 10 minutes and it sends emails to the school weekly. We got them the app on the iPads because they each have an iPad in their cabinet. So we got that app on the iPads, and they learnt about it. And when we went over there yesterday to do our final presentation, which was the official handover to them, to the energy champions, they were showing their peers how to install the app, how to read it, what it did. Just being able to see the spikes, all the curves and the days and stuff, they're really excited about it and because like remember when we were saying like about how much power we made. They all were saying we'd made one Watt and like a hundred Watts or something and stuff. And they're just, they're flabbergasted when we tell them what they actually made.

Hamish: Yep.

Marco: We had a lot of consultations with their teachers about a learning resource for them.

Hamish: Because we had to make it as interactive and enjoyable for them as possible. After we went through how solar panels work, we managed to get a little science kit, which had a ...

Marco: Which one of the teachers over there had originally brought for the kids. But because it was a bit, techy we re-wired it – because the way it was, was quite difficult.

Hamish: The way it was, was you could only run everything if you ran it all off the battery, which would leave the solar panel side of it completely obsolete.

Marco: Useless. It's a representation to show them exactly what's going on. So you turn on a little switch, the solar power, the panel, powers the fan but nothing else so it powers certain things and then the battery, which is the grid, supplies all the rest of our needs.

Hamish: Yeah.

Marco: That's what it is, so … like when you're explaining that to them, there were like, you know, they understood a lot better.

Jacky: We’re always looking for meaningful opportunities to link with the main school and this has been a really authentic learning opportunity for our students and we now hope that they will take some of that learning home and look at ways that they can conserve energy in their home and in the community.

Briar: Our projects are micro-hydro so it’s a water-powered turbine and it creates electricity. We're using it as a teaching tool for our teacher because he is really into renewable energy and so each light bulb is going to use a different amount of power. And so we want to be able to showcase that.

Daniel: It all started off with Iain Charity donating his micro hydro up here. The high pressure mains line comes in through this pipe at the back and comes through a small orifice, a small hole. It shoots out a water jet, which shoots onto little cups [pelton wheel cups]. That spins the pelton wheel, which spins coils of copper. Outside there's a magnet that induces a current, that creates electricity that comes out to power our light bulbs and the vault meters.*

Briar: We can change the orifice size and we worked out the other day that the best orifice size was a six millimetre.

Daniel: With the six mil orifice, it is running at 1,620 revs per minute and at about 85 vaults. The object with that is to have an LED, with that top bulb over there, an LED [eco is the next one down], and then a halogen, and ...

Briar: ... and then an incandescent on the bottom. And so we're going from the top to the bottom. The reason why the LED is up the top is because that's the one that uses the least amount of electricity to run compared to the incandescent, which is down the bottom.

Daniel: We’re connecting these up to the switch so we can select the switch and show the brightness of each separate bulb.

Briar: And then if you've got a house that’s got multiple different types of light bulbs in it, you can turn them all on and show how much electricity that's going to use.

Daniel: There is a lot of water wastage with this.

Briar: That's why we wanted to put in a reservoir so that we could catch some of it and then reuse it for washing hands. First, we took it apart to look at what we were doing and what we were working with. Then we moved onto frame design after we figured out where we wanted to install it because we had to have special specifications. We had to have a certain amount of room to add new gauges and to support the micro-hydro.

Daniel: And then we had to go in the room that's behind here and look at all of the mains copper pipes to see if we could connect this up to the mains through the wall. We made plans on how we were going to set up the electrical box.

Briar: And do the plumbing.

Daniel: And made a schematic for the frame. It was mainly Mr. Dobbin asking him what to do and him giving ideas and then us researching. We talked to Mr. Dobbin about the components we had to get in the box and he suggested Scott Christie, which is the school's electrician. So he organised all of the vault meters and the switches and the east opp and gave us a price. We got all of the components through him. Don Meades came in. He's a retired electrician and he showed us all of the electrical methods to put in the wires from the micro-hydro into the box, how to bend all of the electrical conduit and how to connect the vault meters and that up.

Briar: We’ve worked really well together as a team, we kind of get along quite well.

Daniel: We don’t have that much knowledge of the electrical components and that, so we have been researching together and communicating.

Briar: Yeah and learning while we are trying to install it.

Daniel: I really like hands on stuff and this is the only subject I can really do that in.

Briar: Being in here is so amazing. It’s really a pleasure to be able to work all of this sort of stuff and learn different sorts of stuff that you wouldn't learn in a classroom.

Shannon: This is a solar water heater. It will be placed on top of the staff room and it will hopefully feed hot water to the men's bathroom, the basin, and into the staff room kitchen.

Jason: This is part of a five year plan to reduce our energy consumption. So, it is all renewable energy. I think the challenge for us was that the only thing that we already had was the tubes, so we had to make the manifold and all the framing and do all the design process for ourselves.

Jason: Obviously with a project like this there’s some pretty big compliance standards we have to follow, but we’re lucky being with the school we don’t have to apply for building consent. So we have the ability to put it on there without getting any recognition from the council. To change anything with the plumbing we have to use a certified plumber. We have to do safe practice when we’re going up on the roof.

Shannon: But we will be able to fix it to the roofs and with the guidance of the teacher we should be able to do it.

Jason: Our biggest problem probably would be all the copper, it’s pretty hard to braze and bend copper to get it right. We spent a good time making the manifold. This is our failed version, the first time we tried I burnt a hole in there with the oxy-acetylene gas so, it’s new, it’s different to work with, but once we were used to it we got it done pretty quickly.

Jason: At the end of each of these tubes there is a socket that will fit into here. When these tubes heat up it heats up the socket and there is a pump at the end. There will be water in the tube. The socket heats up the water in the tube, there's a sensor and once the water gets to a certain temperature the pump will turn on and it will start pumping water down to the cylinder and fresh water back up. When all of the cold water gets up here it will start heating up again and then the cycle just continues.

Shannon: This is our first time creating a solar water heater. So Jason came up with the design of the slip on. I’ve never seen this before, so it's been good.

Jason: Pretty much what I designed is something you wouldn't see anywhere else, it’s two channels. What we've done is pushed our tubes through one channel, and then the other channel goes on top like that. So this is the outer channel and this is the inner channel. What they do is they slide together to make it a little bit water tight, just a bit easier to work with.

Jason: I’ve really enjoyed working on this project this year and it’s made me consider a future in renewable energy. I’m looking to do a course with SIT (Southern Institute of Technology), a renewable energy course, which will hopefully set me up for further studies in renewable energy.

Shannon: It’s been fun working with another person. It’s not your own project. So you work with another person and you get to make better ideas. You might come up with something but the other person might be able to improve it. So you can just continue to make that process and continue to get a good design like we have come out with. My first choice would be becoming an aircraft technician which I developed an interest for through metal technology. I like to work with my hands a lot, and the planning stage. I learnt that I don't want to be in an office, I don't want to be making the project and building and rebuilding.

Jason: The best part about it is that it is not all theory. I’m definitely a person that can't sit still for very long, it definitely helps being able to work practically on something rather than just think about it.

Jason: I think we are definitely leaving our mark on the school because not many people can say that they have designed and built a solar water heating system and been able to install it on the school. The fact that we are contributing to that goal to reduce our energy consumption is pretty special.

Dave Dobbin, Metal Technology Teacher

Lucas, Year 13 student

Dave: So Lucas where did you get the wind turbine from?

Lucas: We got it donated from Iain Charity.

Dave: What do you know about the wind turbine?

Lucas: We spun it up on a drill and we got it to 97–100 volts with 2 amps. We’re putting it on top of the old boiler shed on the chimney stacks.

Dave: OK and what height, what parameters do we know about that?

Lucas: 50 feet, so about 15 metres.

Dave: Right.

Lucas: Part of year 13 technology students, and we’re doing renewable energy this year and try and get most of the school costs down, and save energy, and just learn about trying to save energy for the future and once we leave school.

Dave: Have you got any idea what our goal is for the school, in terms of energy reduction over time?

Lucas: 40%

Dave: Yes, in a five year timeframe, that’s right. How will your wind turbine contribute to that?

Lucas: It’s going to be an off-grid system because we don’t have the models and stuff connected to the grid and so it’s just going to power floodlights in the shed. I picked this project because last year I was doing the PV panels so I never really want to do that one again and I don’t know, I just found the wind turbine interesting to do. Year 13 last year, we just made small solar panels just to power phones, or laptops, or whatever we chose. We just soldered them together and made the PV panels. (I) started the year in a group, so there were two of us doing the wind turbine and my partner left school to do an apprenticeship and so after about term two I’ve been working on it by myself, pretty much.

Dave: Can you walk us through what you’ve had to do with this turbine, right from the start? What’s been involved?

Lucas: From the start we had to pull it apart and see what it actually was because we didn’t know anything about them. We just replaced all the bearings, fixed it up, repainted it, tried to put it back together and just spun it up to see how much power it produces – so we had a few problems with trying to rebuild the wind turbine – so we had to replace the three brushes in it.

We found a website online, Carbon Technologies, and we got six brushes donated from them and spent a few lessons trying to cut them down and just sand them to the right shape. Also it had a few seized bearings which we had to try to take off, get the right sizes, get some new ones.

Last week we had two members from the council, John Mandemaker and Lisa Millican come out here and we had a meeting with them to talk about where it’s going and problems we could have with sound from neighbours across the road from the school. Just trying to sort that out so we can have a solution to either put it out there and if it did make too much noise we would just stop it from rotating. Or if it didn’t make too much noise that we’d just leave it there and keep it how it was. So we originally talked to the council to try and see if we needed a resource consent to put it up on the building. Currently just putting all the wires in the circuit together and building a stand or a pole for it to go on. Got all the design finished for making a stand, just putting spigot through the lathe to get it to the right size, then just welding it together and making it ready so we can install it.

Dave: What’s involved with installation?

Lucas: We’ve got to get a crane from Mahy Cranes to take it up and a certified rigger (for safety compliance).

Dave: And when’s that likely to happen?

Lucas: We’re trying to get it on the second week of the school holidays.

Phillip Gurney (Principal, Trident High School): We have two teachers who have a passion for their particular subjects and David Dobbin who is the renewable energy man in the school, he has spent an enormous amount of time in putting into place a variety of different energy projects in the school. The most recent ones, he’s worked with some students who are doing an installation of photovoltaics on our Special Education Centre.

They were able to get these twelve panels. They put them on the roof, they’ve installed them, they’ve been monitored and checked all along the way by professionals so they’ve learnt to work with – in an authentic environment – with these electricians. David has inspired them, he’s opened the doors for these young men to actually discover something absolutely wonderful.

It has provided us with a lot of fun and energy in the staff. Dave comes in on a monthly basis and puts slides up on a powerpoint and shows us how much energy we’ve saved. Over this year, we’ve saved huge amounts of money just in becoming more energy aware. People switching off laptops, switching off computers, not using excess energy. We have our heat pumps on a special timer and this is all Dave’s innovation, so he’s worked incredibly hard to reduce that.

So the renewable energy project is something that could run out of budget very quickly because it is an enormously expensive thing, unless it is very carefully managed. And that’s where Dave has also been very good. He has kept a very tight budget, he knows that if he wants to go over budget and when he’s going to go over budget, he needs to get clearance, so money is an important aspect of it. What he does do though, is that he does tap into a variety of funds and funding sources.

Edwina O’Brien (Trustee, Eastern Bay of Plenty Trust): We have the opportunity to do funding that benefits energy related courses. The renewable energy project has been a fantastic opportunity in our education programme to have people like teacher, Dave Dobbin come in and show us what they are capable of. And we’ve been given the opportunity of giving a small amount of money. It’s not a lot compared to what we do fund to other clubs and organisations and to have that amount of money go forward and benefit the students and the community and to see what they do, is just absolutely fantastic.

Iain Charity(Engineer, Renewable Energy Ltd): I have a company called Renewable Energy Ltd, specialising in heating and renewable energy technologies like solar PV, solar hot water, and biomass heating. The parts had been well used but were still in service but had no real commercial value, so it seemed like a good fit to give them to the school.

Renewable technologies are growing in New Zealand. There are multiple issues around climate change and the need to save energy and not everybody is convinced, so it’s wonderful to see students, that it is their futures that are going to be affected, and it’s great to see them engaged in learning about these technologies. Hopefully that filters through in their adult lives with the decisions they make and the careers that they choose.

Phillip Gurney: The whole health and safety aspect, which ranges from just looking after the teacher, the student, and then the actual OSH requirements need to be very carefully managed, and in those lines working with Dave – bearing in mind that he’s only been in teaching for about three, three and a half, four years now. Prior to that he was working in industry, so he brought that industry keenness and expectation into the classroom, which has also generated a great deal of expertise and management for health and safety, so he’s very aware of that. We are up with the play on that. Dave and I are busy working on getting OSH in as a precursor to them coming in. To come in and have a walk around with us and actually give us some advice in the event that we need them, so we can say, “Alright, this is what you said we needed to do, this is what we’re going to do”, so we kind of get in there early before there is a problem.

So it’s really important from my perspective, that we keep in touch with Dave, as the lead, with the students, and I’ve spent time with them, working and seeing where they’re going and what they’re doing. Then making sure with our building manager that we keep our property in the safest possible position that it can be.