Ground Water Heat Pump

Underground resources ready to be tapped

Six years ago a small Maori trust in the central North Island faced a big decision. Either sit back as passive landlords and collect the rent on the land while a power company tapped its geothermal riches or take a risk and take an equity stake in what is the country's fastest growing electricity source.

Tauhara North No 2 Trust chose what it knew would be the tougher path - but one which it says is already paying dividends. The trust - held by about 800 owners who affiliate to Ngati Tahu - borrowed more than $100 million to take a 25 per cent stake in the $430 million Nga Awa Pura geothermal station, in partnership with state owned enterprise Mighty River Power.

"We were the land owners and knew the resource was there. It was a matter of understanding its true value and wanting to do something ourselves and participate in the venture instead of just leasing the land," said the trust's chief executive, Aroha Campbell.

The station was commissioned early this year and the investment is on track to deliver gross revenue of $20 million a year to the trust, she says.

"The key for the trust is providing a balance between our economic investment which ultimately we want to end up with jobs for our owners and beneficiaries - we want to maintain a balance."

The trust is set to take a further 10 per cent of Nga Awa Purua and has the option of taking an equity stake in an even bigger Mighty River project, Ngatamariki.

"We have been there and we understand what the risks are."

At Mokai a 113MW power station is 75 per cent owned by the Tuaropaki Trust, the rest owned by Mighty River.

Further development is under investigation.

Further north, on the shores of Lake Rotoiti, Maori land owners Taheke 8c Incorporated of Ngati Pikiao have partnered with Contact Energy and exploratory drilling has begun.

Maori have tapped the geothermal resources of the North Island for centuries, first for cooking and warmth, then tourism and now power. And right now energy from the earth is the most cost-effective way of generating it.

From the 1950s to the 1970s it was hydro - massive public works schemes were built on rivers and canals.

Huge dams were built for the ultimate in green energy. For the next two decades, cheap and plentiful Maui shone, providing peaking and then baseload generation for the next two decades before wind became viable around the turn of the century.

For the past 50 years geothermal was chugging in the background and largely under the radar.

Install a Geothermal Heat Pump During Your Green Home Remodel ...

If you strategy on green house remodeling, think about an substitute power supply such as geothermal. It appears counter-intuitive that a technologies which depends on circulating liquid through pipes in the ground could be used to both heat and cool a home, but that’s precisely what a geothermal heat pump (GHP) or ground-supply heat pump does.

What is a Geothermal heat pump? While big-scale geothermal installations employed by utilities rely on hot water under the ground, the geothermal heat pump heats and cools an person constructing using the continual temperature of the Earth (the leading 10 feet of the Earth’s crust are typically between 50 and 60 degrees Fahrenheit).

A normal GHP system consists of pipes buried close to the residence, a heat exchanger, and ductwork in the residence. During the winter, the ground is warm compared to the air temperature so this warmth goes by means of the heat exchanger into the property.

The up-front expense of geothermal as a residence renewable power source is steep. Even so most specialists agree that you can recoup this investment in 5-10 years through decrease energy expenses, generating it even a lot more desirable as a green house remodeling project.

Federal, state, and neighborhood tax incentives and other applications can support offset the price of the initial investment as effectively. With couple of moving components, a GHP system is also durable and requirements small maintenance. Several manufacturers warranty the pipes for 50 many years and the pump itself usually lasts 20 years.

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