The eco-home of a Maserati-driving petrolhead

The snarling bonnet of a Maserati and the cute little rump of a Fiat Panda are the vehicles on display when I crunch onto the forecourt of Harry Metcalfe’s new home in one of the more remote parts of rural Oxfordshire. There are others, stored out of sight, such as the sprawling baroque extravagance of one of today’s super-supercars, a Pagani Zonda. But Metcalfe is no ordinary petrolhead. He is the founding editor of one of motoring journalism’s success stories, the ultra-glossy magazine Evo.

Several things make Metcalfe, 49, different from your average car nut. One is his background – farmer/landowner, rather than journalist or publisher. The other is his house. Metcalfe might burn fossil fuel at a prodigious rate when he and his Evo team are test-driving supercars, but back home he has designed his family a surprisingly low-energy lifestyle that has slashed his utility bills by two-thirds.

Metcalfe’s new house looks traditional, but is heated with a ground-source heat pump rather than oil, gas or electricity. And, as he still needs electricity for lighting and cooking, he makes a lot of his own with a large wind generator. He also harvests enough filtered rainwater for half his needs, storing it in an underground tank. “I am,” he says frankly, “trying to have my cake and eat it.”

Metcalfe, straightforward and likeable, certainly looks more the farmer than the speed freak or media type. The way he tells it, he set up Evo almost on a whim in 1998, being a car enthusiast and sensing a gap in the market as other titles in the field were closing down. Yet, for all his success as an agri-businessman and publisher, only recently has he acquired a place of his own.

Forever the property wheeler-dealer, buying and selling houses and land, he found himself with a large portfolio – but, paradoxically, still lived in a rented farmhouse. That changed in 2002, when, with a growing young family, he bought a 280-acre working farm near Burford, in the Cotswolds. It cost £2m and came with a number of buildings; among them, a short distance from the main farm complex, a small, traditional-looking house that turned out to have been built in 1939. It is this house that, six years and £1.1m later, has become Metcalfe’s new ultra-green manor.

I find the family – his wife, Patricia, and twin children, Charlie and Izzie, 12, plus two dogs – still settling into the new house. They moved in last November, having lived in a cottage up at the main farm, but there’s still some finishing-off to do. Fabric swatches lie about, earth-moving is taking place outside (Metcalfe likes driving a digger as much as any other vehicle), the new garden is not yet established, the long games room above the garage building outside is unfinished and there’s that general impression of furniture jostling for position. But the surrounding fields – populated, somewhat surreally, by the woolly alpacas that Metcalfe favours (“I like their Dr Dolittle look,” he remarks) – are well tended, and you get the impression that the new house will quickly bed down into the landscape.

Metcalfe may drive carbon-fibre vehicles capable of speeds above 200mph, but, domestically, despite having an unlisted house outside the local village conservation area, he chose to go down the traditional route rather than attempt radical modern architecture.

Peter Yiangou, a Cirencester-based traditionalist architect and country-house specialist, fitted the bill. And what he and the local craftsfolk have produced is so big that the original house becomes merely one wing of the new five-bedroom complex. Before, it was 2,000 sq ft: now it is nearly 5,000, plus another 3,000 for the garage and games block, designed to look like an agricultural outbuilding. This, apparently, was a smaller design option than some they considered. Even so, the moment came when the family chose to sell a holiday house in Italy to fund their ambitions back home.

Just as the 1939 house was a faithful continuation of the ancient Cotswolds style, so the new parts exactly mimic the old, right down to the way the individual stones (from a local quarry) are dressed. A regrettable earlier flat-roofed extension was demolished. The new leaded windows are double-glazed, the house is heavily insulated and there are bathrooms everywhere. But logs burn in the grate in the large stone-flagged hall downstairs, and, when you step in through the front door beneath its carved stone cowl, it is only the obvious newness of everything, and the modern kitchen, with its mandatory Aga, that show you are not still in the 18th century.

The cutting-edge technology comes in the house’s energy and water systems. “We’ve got to be really careful about how we use oil,” Metcalfe says. “Putting oil into an old boiler to heat a house is not a very efficient way to use a valuable resource. Cars are mobile, so they have to use a mobile energy source – and petrol is perfect – but houses are fixed. So I got interested in finding other sources of energy for the house. What amazed me was the efficiency of the ground-source heat pump.”

Metcalfe project-managed the building work himself. As a farmer, he considered growing his own biofuel, but rejected this as too inefficient. Ground-source heat pumps, he found, act much like refrigerators in reverse. Loops of flexible pipes buried in trenches in the ground outside collect the few degrees of near-constant warmth present in the soil. This free heat is passed through a heat exchanger and concentrated to provide background underfloor heating for the house.

Heat pumps can gather up to five times more energy than they spend pumping fluid around. Unfortunately, they don’t make water hot enough for baths and showers; Metcalfe has a high-efficiency immersion heater for that.

A large heat-pump system such as Metcalfe’s, including all the trench digging, comes at a cost: £20,744 in his case, less a grant of £1,200. It generates 28 kilowatts of heat, enough for several small houses. “It’s a brilliant system, but it’s disruptive,” he warns. “Putting it in destroys your garden.” Not everyone has the land to do what he did: capitalise on all the earth-moving to create an 18th-century-style raised lawn, or ha-ha, around the house.

He has a separate air-source heat pump in a shed for his outdoor pool, which makes sense – you use pools in the summer, when the air is hot, so why not put some of that heat in the water? It cost about £850 more than the big oil-fired boiler he would otherwise have installed, but costs a third as much to run.

As for the underground rainwater tank, that is a 6,500-litre polyethylene model that automatically tops itself up from the mains if it gets too low. The family use it for lavatories, dishwashers, garden irrigation and replenishing the pool. It may seem an extravagance at an installed cost of £4,250, but it saves £450 a year in metered water bills.

Then there’s the only bit of all this technology you can actually see – the wind generator, a medium-sized one that cost £18,000 fully installed, less a grant of £5,000. It is about the same size as the wind pumps that used to be a familiar sight in the countryside, but this was the one aspect of the house that the local planners got edgy about, insisting on approval from everyone from the Civil Aviation Authority (the RAF Brize Norton air base is not far away) to the British Horse Society (in case it made the nags bolt). This took ages.

The planners, meanwhile, did not seem bothered about the enormous new house at all – maybe because it’s designed to look old. They did insist on authentic iron gutters and the correct mortar.

So, there is Metcalfe, in a big house, using a lot of energy – even his cars are pampered with their own underfloor heating – but with a clearer conscience than most. He is by no means an off-the-grid, zero-energy person, and he could do more – such as recycling “grey water” from baths to use on the garden, or covering his barns with electricity-generating photovoltaic panels. But he has done a lot, and, as he says: “The net result of combining turbine technology with the latest heat pumps is that annual running costs are a third of what they would have been had oil been used.”

If he’d heated everything by oil instead, he calculates, that would have involved burning 14,000 litres a year at a current cost of £7,280 – it’s a very big house. “People get obsessed with the payback period – how long will it be before it covers its costs?” he says. “That doesn’t bother me. I just think that, in 10 years’ time, a really efficient house, free of oil, will be worth more than one that slurps up oil.” My own rough calculation is that it would take about 12 years for Metcalfe to cover the investment costs of this alternative-energy technology at current prices – though a much shorter period if conventional-energy prices continue to spiral upwards.

While the ground-source heat pump is superefficient and constant, the air-source pump is effective only in summer and early autumn. And the wind turbine is, of course, dependent on the weather. Even so, it contributed 19% of Metcalfe’s electricity in the month before Christmas. He knows this because he has an outhouse full of dials and gauges that tell him.

Moreover, he gets a big discount from his electricity supplier because his wind-turbine output counts towards their green-energy targets. All in all, Metcalfe doesn’t look remotely like someone who has backed the wrong horse. Besides, he’s doing it as a matter of principle: save precious oil for supercars, don’t waste it in boilers.

Of course, Metcalfe and all the other well-heeled country types could save even more energy by moving into a snug city apartment, giving up their cars, and going everywhere by public transport. But he’s doing a serious road test of something that is going to become familiar: microgeneration. If he can do this now, the rest of us will be doing a smaller version of it when costs fall in a few years’ time. And if petrol gets really scarce, Metcalfe says that most of the time, he doesn’t even need to drive his Zonda. He just likes to stand and look at it.

Eco-livingthe Metcalfe way

1 Ground-source heat pump from Viessmann (www.viessmann.co.uk).
Cost: £20,744 (minus a grant of £1,200).
For: conjures free warmth out of the ground for water heating; works year-round.
Against: involves lots of messy trench-digging.

2 Air-source heat pump for outdoor swimming pool from Calorex (www.calorex.com).
Cost: £4,780 (£850 more than conventional heating).
For: great in summer, when you’re using the pool.
Against: no use if you fancy a winter dip.

3 Wind turbine, 6kW model from Proven Energy (www.provenenergy. co.uk).
Cost: £18,000, fully installed (minus a £5,000 grant).
For: you get green-energy rebates, as well as lower bills.
Against: best in exposed locations and wide-open spaces. Some planners dislike them.

4 Rainwater harvesting system by Freerain (www.freerain.co.uk).
Cost: £4,250.
For: can save you half your metered water bills.
Against: costly to get that big tank buried.

5 Double insulation. No matter what the power source, better insulation saves energy. Metcalfe used both conventional thick glass-fibre insulation and advanced reflective thin-quilt “multifoil” insulation (such Gauges in the pump room keep track of green-energy output as Triso-Super 10, www.tri-isosuper 10.co.uk).
Cost: multifoil is about 10% dearer than glass fibre.
For: everything.
Against: multifoils require skilled installation.

Consider also: roof-mounted solar water-heaters; roof-mounted photovoltaic panels, to generate electricity; grey-water recycling, for use on the garden.