Power to Remote People
By GALLOWAY, Iain
Imagine never having to pay another power bill and being able to rely on “green” electricity for your energy needs. Jill Galloway went to the Totara Valley field dayon small alternative energy generation. ——————– The local farmers run their households, farm cottages, workshops, coolstores and woolsheds on alternative power provided by a wind turbine, mini hydro system, solar energy and a biodiesel-fueled generator.
Any spare electricity goes into the national grid. If there’s a shortfall the lights don’t go out, but the houses start paying for power like city folk.
Power bills are a combination of the power used from the national grid (debited) and the power put into the national grid, for which they receive a credit.
The Totara Valley sustainable energy project is Massey University’s baby, but it has help from the Crown Research Institute partner Industrial Research Ltd (IRL), which provides some of the technical expertise, equipment and metering. As well, sponsorship has come from various electricity companies, such as Main Power and Scanpower, that have a growing interest in the future business opportunities.
The director of Massey University’s Centre for Energy Research, Ralph Sims, says the future will be small, effective, affordable and renewable power generation.
“Today, big central power generators are what we depend on. In the future, they will be supplemented by thousands of small, distributed generation plants that will become more dominant.”
That puts systems such as the Totara Valley at the top of the list.
It is in a remote valley out of Kumeroa, east of Woodville in the Waewaepa hills and at the end of a rural power line. It consists of a mini-hydro turbine, a wind turbine, solar panels and biodiesel unit that all help provide power for four households.
“It depends on how much wind there is, or sun as to how much electricity the system provides,” Prof Sims says.
The wind turbine is two kilometres away from the houses up on a windy hill. To put lines in to carry electricity to the houses below would have been $26,000. Instead, the wind energy was used to convert water to hydrogen. The hydrogen is then piped down to a woolshed in the valley where it is converted back into electricity in a fuel cell.
It is a cheaper alternative, even with converters at both ends and the hydrogen pipe as it means up to six hours of energy can be stored in the alkathene gas line.
The yellow pipe that carries the hydrogen only cost $6000 to buy and bury. The storage factor is also very attractive. Otherwise it means electricity gets stored in batteries, and that’s an expensive deal.
James Hargreaves, a Massey lecturer, helped post-graduate students design and put in the wind and water turbines.
The water pipe has a fall of 165 metres and is 1.3 kilometres long. The pressure is about six times that which would come out of a house- hold tap. So the water turbine has to cope with that very high pressure. It’s not just flow, but the pressure head that makes a water turbine work efficiently.
Dr Hargreaves says this system really pushes technology boundaries. He jokes that it is something of a surprise and joy that it is still working at all.
There are aspects of the alternative energy system that make it a world first.
“There has been a lot of talk about turning wind power into hydrogen then using a fuel cell to make electricity. This is the first time anyone has combined that with all the other technologies here,” Prof Sims says.
It is small scale, but unique in that it is distributed generation in a rural community where the line company is involved as well.
“The electrons are going up and down the power line and Scanpower, the lines company, has control of the biodiesel generator and the hydro system, as well as the water heating and cool stores, and can turn them on and off when they want so that demand matches supply,” he says.
“It is a symbiotic relationship between the land owners who have the resource and the line company that can reduce power losses and on-sell the excess power.”
For all that, if Massey was starting the small generation system again, after four years of testing it would do some things differently.
“We’d look at energy efficiency first. Given the funding, we know we could cut the present demand in half. That’s the basic stuff, because it is expensive to produce electricity using wind or mini- hydro. So the first thing to do is to try to decrease the demand.”
.5Then there is the generation itself.
“We have a heat pump in one house to heat water that we haven’t monitored and the owners are very happy. Next door they have a solar water heater and they’re also very happy with that. We’d like to know more about which one works best.”
The wind turbine hydrogen would give far more value if it wasn’t converted back into electricity.
“That conversion means two- thirds of the energy value is lost. The gas could be used directly for heating water, cooking – those sorts of things, just as natural gas is today.”
It has been an interesting learning experience, that has been fully utilised by Massey. It has been home for many graduate students who have done their research at Totara Valley.
“All of sudden people are thinking about this technology and I guess we are a few years ahead in New Zealand.”
Prof Sims is on secondment to the International Energy Agency in Paris at the moment and it is watching the Totara Valley scheme with interest. It combines three of the IEA’s interests and international agreements; grid distribution, electricity networks and hydrogen. “With the IEA interest, there is the chance for other people to feed information into this and learn from it, too.”
It is also exciting for the farming community, which likes the idea of “green” electricity.
“Mrs Poulton, the most senior member of the community, says she’s been waiting for this for years. It’s just what the community needs she reckons,” Prof Sims says.
There is a potential in the future for New Zealand farmers to farm both livestock and for energy.
Large wind turbines sited on private farms in Manawatu and Tararua already provide income for the land owners.
Mike Poulton, who farms in the valley and is a user of Totara Valley electricity says it makes little difference to the way his house and woolshed are run. The mini-hydro system is on his farm. Like others in the valley, he likes having the small electricity generation in the area.
Mike Pattie is from the lines company Powerco. He tells the field day that under current legislation, 2013 is the time line companies can consider disconnecting uneconomic lines. They would largely be in the more remote rural areas.
It is not cut and dried yet though. The Government is undertaking a review of the legislation at the moment.
“There is still a big question mark over that. One of the main interest groups, Federated Farmers, has done a submission on it. Submissions are coming in at the moment.”
In many of the far-flung areas, the lines were built with subsidies and they have never been economic, Mr Pattie says.
Powerco is planning a similar project to the Totara Valley one running at the moment, as it looks at alternatives to maintaining uneconomic lines in remote areas.
“We’re trying to get a win-win for Powerco. We might come to an agreement with the Government and customers where we disconnect the lines, but set up an alternative power system, which supplies what they’ve got at the moment.”
Massey University’s and Industrial Research’s Totara Valley system shows small can be beautiful and it looks likely to be the way of the future.
It is something small, remote rural communities need to watch as the possibility of power line cuts could become a reality. Then there is also a chance that farmers might rely for their income on livestock, small hydro systems, solar and wind turbines – in equal amounts.
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(c) 2007 Evening Standard; Palmerston North, New Zealand. Provided by ProQuest Information and Learning. All rights Reserved.