The Eco-House

Here is the excerpts of something which has the potential to trigger the revolution of the millenium…

The whole idea and all kudos must go to Mr. Michael Rea and Duncan Price. A zero carbon house has been built on Britain’s most northerly island of Unst, which will bring obvious benefits to the environment.  The carbon neutral home lowers the carbon footprint by producing its own energy and storing it to heat the home.

Background of the project

“Our zero carbon house is being built on the island of Unst, Britain’s most northerly island in the UK.  We have owned the site on which we are building since 1983. The original building was the Unst headquarters for Alexander Sandison Ltd (still trading on the island to this day) which included a shop, a chandlery, a sail making/repair and net repair service and two ovens for baking bread.  Prior to this it was also home to the Old Batavia hotel”, says Michael. Sadly, in 1992, the island was hit by hurricane force winds and the building was so badly damaged that we were ordered to take it down completely, leaving us with just a Brownfield site. This occurence hastened a new beginning.  We decided to build a new and completely different house on the site and set out off to Canada and Scandinavia, as well as areas of the UK, for ideas.  After much research, we opted for an off-the-shelf house from Scotframe – a company based in Inverurie, Scotland, whose houses were found to be the most efficient and easy to heat.  In 2001, we met Dr Jeff Kenna, Chief Executive of Energy for Sustainable Development, now an AIM-listed company and one of the largest sustainable energy consultancies with offices throughout the world.

When Dr Kenna learned of our plans to build on the most northerly isle of Shetland, he suggested that we should build an eco-house.  This idea struck a chord and we started researching the technology that would be required for such a project.  By this time we had moved back to Unst so our research was done remotely by telephone and email.

Together with Dr Kenna, we put together a proposal to the Carbon Trust for funding but this was turned down at the time for being “too innovative”.  It was at this point that we decided to fund the project by seeking private sponsorship.

Since then, companies have been coming forward to help, either financially or by providing discounted services, to get the house up and running.  We are eternally grateful for all of our sponsors’ support – the project could not have happened without them.

Benefits of the project

The carbon neutral home lowers the carbon footprint in many ways.  First and foremost, it produces its own energy, storing it via a flow battery/fuel cells.  In addition, an electric vehicle will be used for transportation and, as we are generating our own energy in order for the vehicle to recharge, the need for fossil fuels is removed.

Food will be grown in high-tech greenhouses using a hydroponic growing medium and LEDs which use only a small amount of energy to manipulate the plants and extend the growing period. Later this year, 2008, they will be using a thermal imaging camera to check the thermal properties of the house for leakage etc.  As well as the obvious benefits to the environment, it is hoped that the Zero Carbon House project will benefit the island of Unst by helping to raise the profile of a fragile island community.  The house is attracting tourists and a great deal of media attention already including a write-up on Google, one of the world’s largest search engines.

Aim of the Project

To pilot an approach to carbon-neutral living that can be replicated across the UK and elsewhere.

Major Objectives

1.  To construct a highly efficient, low embodied energy house on Unst, Shetland.

2.  To install a low carbon energy system compromising two micro wind turbines, an electric car, an air to water heat pump, watery battery heat store, power store and control system.

3.  To monitor performance of the energy system in real time, using students on placements staying in the house to experience zero carbon living, and expert consultants.

Characteristics

· Technical risk is minimized by use of familiar robust technologies from well respected Scottish, UK and international manufacturers and suppliers.

· Integration of an air-to-water heat pump, hot water battery and underfloor heating with an innovative domestic hot water system.

· Financial exposure of any one party minimized by holistic demonstration of the system on a small scale that can attract a range of financial partners to learn together.

Projected Outcomes

· Pilot of integrated approach to low carbon living that can be replicated across the UK and elsewhere.

· Demonstration of micro generation technologies to power house, transport and food production.

· Development of market for micro generation in Highlands and Islands by demonstrating a system that can be implemented on remote grids and “unplugged” if required.

Project developments

Building plans began with the standard off the shelf timber frame provided by Scotframe. The whole of the UK, including Shetland, is viewed as a maritime environment.  Lightweight structures operate much more efficiently in this kind of environment, taking less time to heat.  The design of the structure had to take into account the severe weather conditions of Unst.  The Scotframe structure is very substantial – not a stick frame structure – and the wall plate is anchored to the underbuild at 400mm centres using stainless steel bolts which should allow the building to endure the extremely strong winds that can often occur in this area. The house was shipped to Unst on two articulated loads.  These loads included the complete house, minus the roof e.g. frame, insulation, doors, windows, plasterboard and flooring. A water battery has also been developed, which is a 4200 litre GRP tank with 200mm of Celotex insulation.  This is the buffer tank for the air-to-water heat pump and the underfloor heating system.  Within the top of this tank is a large titanium coil.

Greenhouses and hydroponics

A high-tech insulated greenhouse, approximately 94 square metres, will be erected on land opposite the zero carbon house.

An external sculpted soil wall will protect the greenhouse against the weather extremes.  Food will be grown throughout the year using the hydroponics growing system – no soil or peat is used for this process, just nutrients and water.

LED lighting will enable five crops a year to be maintained.  Using an electric vehicle for the distribution of this food crop means that no fossil fuels are used for transport purposes.  All waste material will be composted and used for external raised-bed food culture. Rainwater from the roof and spring water run-off is being harvested.  This will be put through a reverse osmosis plant to remove heavy metals and then used for the hydroponics project.