Keeping warm, however, was a different story. Three quarters of the community drew gas for their boilers from a Calor Gas tank kept on site, which had to be topped up regularly by tanker delivery. The pipes for the system were old and dangerously leaky, meters needed replacing and every year the price of off-grid gas would spiral upwards. During the winter some of the community were paying up to £200 a month for gas, despite living in well-insulated homes. For Marion Briggs, one of Hoathly Hill’s residents, seeing the back of the Calor Gas system became a personal ambition.
The idea of using renewable energy as an alternative had been a community dream for several years, but it wasn’t until Briggs met renewable energy expert Stuart Boyle, who was house-hunting in the area, that the ideas began to take shape.
Boyle encouraged the community to seek funding for a feasibility study, which would look at what sources of energy the site might be able to use. Money came from EDF Energy and the Forestry Commission, both of which showed immediate interest in the project. The results of the study indicated that the community was a good candidate for a wood-fired district heating system, in which a central wood-fired boiler burns forestry waste and pumps the hot water through an insulated pipe to each home in turn.
Even at this early stage, a network of different people had begun to develop. Working on behalf of the community, Boyle had begun talking to Mike Cade, a consultant engineer with experience of installing heating systems. Cade was keen to be involved, even though he knew the project was ambitious. His advice on how each of Hoathly Hill’s 27 houses could be connected to the boiler would prove invaluable.
The involvement of Forestry Commission officers Patrick McKernan and Matthew Woodcock gave the community an opportunity to meet its future fuel supplier face to face. Where once there had been an impersonal contract with Calor Gas and the monthly arrival of a gas tanker, there was now the listening ear of Jamie Kirkman, owner of nearby Balcombe Sawmill and a man with a waste problem.
‘Before I met the Hoathly Hill residents I was looking at a very big pile of wood waste thinking, “What the hell am I going to do with that?”’ he remembers. ‘I used to nearly cry when I’d watch a lorry carry £200 of wood waste out of the mill to the nearest landfill.’ By selling Hoathly Hill 250 tonnes of wood waste every year from his sustainable forestry operation, Kirkman realised he could solve part of his growing waste problem and develop a valuable by-product. The residents of Hoathly Hill realised they would have the benefit of knowing where their fuel came from, as well as having a guaranteed, reliable supply.
Marion Briggs went back to the community armed with the feasibility study and the knowledge that the wood fuel supply would be both sustainable and local. Although she had secured £160,000 in grants, she still needed the residents to agree to put up some £240,000 of their own money towards installing the new system.
‘Some people wanted convincing,’ she remembers. ‘They wanted to know why we weren’t doing Combined Heat and Power or ground-source heat pumps, but once we explained our thinking, nearly everyone was in agreement. There was a real drive in the community to move towards renewable energy.’
The network started to grow. A loan with a favourable rate was set up with Triodos Bank to allow households without immediate funds to pay their share towards the boiler. An architect who had worked with the community before and was familiar with the Steiner principles of anthroposophical design (architecture as a response to natural forms) was brought in to design the boiler house. The main contractors, Douch Partners, were well known to the community and sympathetic with the unusual demands – both technical and architectural – of the project. Drawn by news of the scheme, wood fuel pioneers began to arrive at the community to offer advice. Even the local council pricked up its ears.
All told, from start to finish, 90 or so people were involved in installing the boiler. For many, it was their first experience of such a project, but is unlikely to be their last. Boyle and Cade now both have booming businesses installing renewable energy heating systems, and sawmill owner Jamie Kirkman is even thinking of having his own boiler installed.
Not everything went smoothly, however. Initially, the community faced a volley of protest from nearby residents over the proposed site for the boiler. Concerns over noise, smoke and obstruction halted the planning application – but this was an important step in itself.
‘It forced us back to the drawing board and made us more aware of the project as a whole,’ Briggs explains. ‘We had to research the system further just to answer the planning department’s questions.’
In the end, a special low-profile building was designed, which had to accommodate the boiler itself, two 4,000litre water tanks and a storage area for wood chips. No expense was spared on the project’s environmental credentials. A computer was installed to monitor the boiler’s flue gases continuously, keeping emissions of particulates and nitrous oxides to an absolute minimum. And the ash? Mixed with compost and used on the community’s gardens, and shortly to be employed as a glaze in the nearby pottery and sculpture workshop.
The most challenging part of the project was laying 1.4 kilometres of insulated heat pipe from the boiler to each of the community buildings and houses. Every patch of gravel, grass and concrete had to be perfectly restored and no house left without heat for more than a day.
What could have a been plumbing disaster was instead embraced by the community and contractors alike. A children’s story told in the playschool of a ‘black worm’ coming to Hoathly Hill led to a christening for the pipe itself. ‘Black Boris’, as the conduit came to be known, was happily recognised by children across the site, and its arrival eagerly anticipated in every home. The first flow of hot water from the system brought a surprising response, Briggs recalls. ‘Compared to the gas system we had before, our relationship to heat has changed fundamentally,’ she says. ‘People would walk into their homes and swear the “quality” of the heat was somehow different to what they had experienced before. They couldn’t quite put a finger on it, but the difference was there.’
The residents’ experience reflected how completely they had come to identify with the project. Heat to them now has a face, an origin and a meaning; they can see where and how it is generated, and many will personally know those involved with every step of its production. As smoke begins to twist from the boiler’s chimney at its inaugural opening, assembled guests are full of questions. Could it work elsewhere? Is it sustainable? Do we have enough wood chips? Are companies interested in installing biomass boilers?
Each of the members of Hoathly Hill’s now-extensive network has an answer. Engineer Mike Cade explains that once you point out to large housing companies that installing a central boiler will allow them to sell energy to residents for life, they suddenly become interested. Matthew Woodcock estimates that a single acre of woods could provide an average home with a year’s worth of fuel, and points out that the South East alone boasts 270,000 acres of managed woodland. He stresses that the UK’s woodlands need to be managed for them to remain biodiverse and healthy. Mill-owner Jamie Kirkman reckons he could supply three or four more boilers if the demand existed.
With their wood heating system humming quietly away in the background, the Hoathly Hill residents are already pressing ahead with plans for on-site wind turbines and biodiesel generators: ‘Our aim is to be as sustainable as possible,’ Marion Briggs says frankly.
Closing their doors to the winter chill, they settle down to a season of half-price fuel bills and the faint, pleasant smell of wood-smoke drifting overhead.
Mark Anslow is the Ecologist’s senior reporter.
This article first appeared in the Ecologist April 2009