PUBLISHED: 09:11 10 March 2014 | UPDATED: 11:11 11 March 2014
We've all seen the headlines about fossil fuels running out, energy bills spiralling upwards and rocketing prices for oil and gas. And most of us know only too well how expensive it is to heat our own houses these days.
The National Trust, being both a charity and a conservation organisation, has double the reason to look at alternative ways to provide energy for the places it cares for. Getting off fossil fuels and on to sustainable energy has become much more than an ideal – it is an important way to save money.
Because of this, the charity is currently rolling out technologies fuelled by renewable resources, often using raw materials harvested from its own land. Special biomass boilers are to be installed at several of the trust’s large country houses, including Ickworth House near Bury St Edmunds in Suffolk, as part of a pilot national investment programme.
As a forerunner to this scheme, some smaller places are already embracing the technology, including Sheringham Park on the north Norfolk coast. Thinnings and other timber with little other value – harvested as part of routine management at the large estate in a process essential for the healthy maintenance of the woodland - are now used as fuel for the boiler.
Miranda Campbell, the National Trust’s environmental practices adviser says: “Burning wood has been used for heating for thousands of years. What’s changed is our approach and the way we do it. Woodchip, sourced from timber that has been generated as part of our normal woodland conservation activities and management, is our replacement fuel.
“The term biomass relates to a fuel that is developed from organic materials, a renewable and sustainable source of energy, which is used to create forms of power. When we burn the wood, the energy in its biomass is released as heat. So, if you use logs in your open fire or woodburner at home, you’re already using biomass.”
The heat generated by burning the woodchip is used to provide heating and hot water for the visitor centre and the surrounding buildings.
“The new boiler is already keeping a lot of buildings warm and supplied with hot water, including visitor reception, the café, toilets, holiday cottage and estate team offices and workshops,” says Miranda.
“This means the areas you experience as visitors are now completely off oil and electricity. By removing reliance on the volatile fossil fuel market, we’re also eliminating risk of oil pollution from spills or leaks and reducing our carbon emissions.”
Burning oil causes greater pollution than woodchip, there are greater implications for pollution in the refinery process and it also involves greater transportation and processing costs. The use of wood harvested from the estate cuts down this pollution and also presents a much more sustainable – not to mention cheaper – solution for the trust.
“We’re expecting to use around 35 tonnes of woodchip per year, a similar volume to one-and-a-half double-decker buses’ full,” added Miranda. “It starts off as timber of low grade commercial quality, extracted from the park and subsequently chipped by volunteers – the key is to dry the woodchip enough so that the boiler operates easily and efficiently. So we’re chipping about 60 tonnes of timber in a batch, allowing the wood to gradually dry to a point when it is ready.”
Using the biomass boiler is very simple. A very large container is loaded with chip, which is then automatically fed into the boiler. The woodchip is burned and the heat used to provide hot water. The hot water is then stored in a large accumulator tank (which holds around 1,750 litres of water) before being fed into a network of highly insulated pipes below ground leading to the various buildings.
Saving money and saving our heritage
Because the trust is investing in its own local natural resources, rather than relying on a large oil company with its associated mass drilling, extraction, processing and distribution infrastructure, there are cost savings in fuel bills, as well as benefits for the environment.
The trust also gets an income annually through the Government’s Renewable Heat Incentive, which pays the charity for the heat generated and used. That’s really good news, as it is money which can now be used for conservation work instead of paying fuel bills.