The Zero Carbon House Project

As we move towards a potential fuel crisis, with rising gas, petrol and electricity prices, the world needs to do all it can to take advantage of renewable energy sources. Many people have doubted, however, whether such an approach could realistically be applied to a domestic premises. A house on Unst, Britain’s northernmost island, may now quell those doubts.
In 2001, Michael and Dorothy Rea, a retired couple from Wiltshire, England, decided to design and build a house which would be completely self-sufficient: an ‘off the grid’ house which would eschew the need to consume gas and electricity and instead produce its own energy.

With the help of Dr. Jeff Kenna, Chief Executive of Energy for Sustainable Development, and a host of generous sponsors, the Rea’s vision of a carbon neutral house is coming to fruition.

Utilising solar panels and wind turbines, the house, known as Batavia, is capable of producing its own energy which is then stored in fuel cells and used around the house. These cells also charge the Rea’s electric car, a refitted Toyota Yaris, which can travel almost 200 miles on a single charge and reach speeds of over 45mph without using fossil fuels.

A 94 square metre hydroponic greenhouse will provide the food to satisfy the Rea’s vegetarian diet, with low energy LEDs (which also provide light throughout the house) ensuring an extended growth period. No soil or peat is required. Instead, five crops a year are maintained by minerals and rainwater harvested from the roof. The electric car allows this food crop to be distributed without the need for fossil fuels.

Heating is provided by an air-to-water heat pump. The device, which requires very little site work, extracts heat from the surrounding air via a series of heat exchangers which operate a reverse refrigeration process. Accompanying this is a heat recovery system. This passes all the air in the house through a filter which recovers 90% of the heat and reintroduces it throughout the house. The remaining 10% of the heat is directly recovered by the air-to-water pump via insulated ducts plugged into the pump’s inlet.

The house itself is a simple, wooden kit house from Scotframe, a company based in Inverurie, Scotland.

zero carbon house

It is worth noting that none of this technology is particularly novel: wind turbines, solar panels, the air-to-water heat pump and the house materials have all been standard fare on the market for some time. What is novel, however, is the amalgamation of these technologies into a single, carbon neutral, house. The feat is particularly impressive considering Unst’s harsh climate where winds reaching 100mph have previously claimed lives. It is undoubtedly a testament to the relative ease of building a self-sufficient, environmentally friendly house and will hopefully stand as an example to promote carbon neutral, off-grid housing. As Dorothy Rea put it, “if we can do this here, anyone can do it anywhere.”

You can find more information about the Zero Carbon House Project at http://www.zerocarbonhouse.com.