Anna Shepard, Eco Worrier

When I told my family we were going to spend the weekend in a brand-new zero-carbon house, there were stirrings of enthusiasm. That was before we looked up where it was.

Greenwatt Way is in the Slough suburbs, just off the M4. The complex — made up of ten prototype homes, and funded by energy provider Southern Electric — is directly under the Heathrow flight path, nestled between a Murco petrol station and an electricity depot. Not quite living the green dream after all.

On the way there, my boyfriend complained bitterly about the location, while our two-and-a-half-year-old son, Owen, repeatedly asked what would be “special” about our new house.

According to the Government, homes like these will soon be the norm. It has pledged that all houses built from 2016 will be zero carbon, hoping to reduce CO2 generated by domestic homes, which accounts for 27 per cent of overall CO2 emissions. But this is not just a green solution. The nuclear crisis in Japan, combined with the instability in the Middle East over recent months, throws into sharp relief the importance of supporting renewable technologies. Now, more than ever before, Greenwatt Way seems like the way forward.

As a green writer and eco enthusiast, I’ve visited lots of low-carbon houses, but this is the first time I’ve spent a night in one. I’m curious to find out what it’s like to live here; do all those tiny green tweaks and energy-saving appliances get in the way of daily life?

Except for the electric Mini that is charging outside our front door, our three-bedroom house looks like any other modest new-build. Inside, it’s modern but not in a chrome, minimalist kind of way. We love the open-plan kitchen and dining room. While I cook, Owen can watch cartoons on the eco-friendly flatscreen.

Upstairs, it’s comfortable and simply decorated with a spacious double bedroom with a shower room attached, another bedroom with bunk beds, and the smallest being used as a study. There’s also a family bathroom. There are few obvious signs of green virtue, except we notice that the building feels more solid than most new houses.

My biggest relief is that it doesn’t smell. The last zero-carbon house I stepped inside was so stupendously airtight that it gave off an unpleasant pong. Here, there’s a clever ventilation system that gets rid of stale air once its heat has been extracted to warm up incoming air.

Owen spends the first afternoon racing up and down the stairs, declaring that the bath makes monster noises. This turns out to be a pump that sucks up water when you run the taps, storing it in a tank to use later for flushing the loos. Some of the other houses use rainwater, collected in a vast underground tank in the garden, to flush the loos. And there’s a button to press if you dye your hair, as the chemicals disturb the system.

Our neighbours are mostly employees of Slough council and Southern Electric who have opted to live here for a year, renting the one, two or three-bedroom homes for a bargain price (£570 a month for a three-bedroom) in return for monthly feedback.

“Very little is understood about what these kind of houses are like to live in,” explains Wendy Pringle, zero-carbon homes development manager at SSE (the parent company of Southern Electric). “It’s an important part of the project to get normal people, particularly families, living in them, to find out what they think.”

We’re impressed by how warm it is. There is no central heating, only one tiny radiator that is barely switched on, but the house responds magically to body heat. One of its main features is a virtually airtight structure with enhanced insulation and triple-glazed windows. The walls are so thick, we can’t even hack into our neighbours’ wi-fi account (with permission, of course).

This means it retains warmth brilliantly. Turn on the oven, hob or the low-energy TV and you soon notice the difference. Compared with our draughty Victorian terrace in London, which is generally freezing except when you hang the expense and blast the central heating, our eco-home maintains a steady temperature day and night. We become increasingly obsessed, running over to check that the radiator is still off, then checking the thermostat, which is generally around 21C. It’s the eco-marvel of our stay.

Since there’s no gas, electricity is crucial. It comes from PV (photovoltaic) cells, an efficient breed of solar panel, but you can’t store it up, so if you’re out during the day, when it generates power, it will send the extra energy back to the grid. During the evening you may need to draw on the grid, but it will be offset by your contributions during the day. “Residents get used to trying to do things slightly differently … doing your vacuuming and washing before it gets dark, for instance,” says Pringle.

If our weekend home goes beyond current definitions of zero carbon, that’s because no one can decide what they are. Over the past few years there has been endless squabbling about how strict to be; whether to include energy costs involved in construction, and whether a truly zero-carbon house must have emitted no carbon by the end of its lifespan.

Last week the Zero Carbon Hub, set up to co-ordinate green housing policy, announced its recommendations. A “zero”-carbon home — a level 6, the highest in the Government’s Code for Sustainable Homes — must have an energy-efficient structure but it is allowed to have a small carbon footprint (2 tonnes per year, compared with 8 tonnes produced by an average modern house). However, it must mitigate its emissions in some way, for example with off-site renewable technology. This clause is still being worked out (despite a pre-election promise from the Minister for Housing, Grant Shapps, that he would define zero carbon once and for all within weeks of winning the election).

Although the weather is foul all weekend, we’re determined to enjoy the secure communal garden. As well as a private area for each house (shed, compost and recycling bins, water butt), there is a bike store and raised beds for vegetable growing. Our neighbours all speak up for the outdoor space: from the sofa in the open-plan living room and kitchen, you can keep an eye on children as they tear around outside.

The only complaint that trickles our way is about the noisy ventilation system. On our first night we notice a gentle hum. It’s a bit like going to sleep with a bathroom extractor fan left on. In the attic, pipes are sucking out damp air while warming up the fresh stuff. The noise doesn’t bother us; we sleep like logs and we’re grateful in the morning, when we fry bacon and eggs, that the greasy smells quickly disappear. It is just one of many gadgets that make the house feel alive. Unlike most inert buildings, there is a constant whirring of one sort or another.

Yet I’m surprised how discreet and unimposing most of the green technology is. It comes across as being efficient and clever rather than green. The induction hob heats only the saucepan, not the area around it. Smart meters gently remind us how much electricity we’re using, flashing red, amber or green. Meanwhile, the washing machine uses renewable energy from the energy centre to heat the water.

When we leave the house for a few hours, we remove a card near the front door and all the lights and electrical equipment power down, except the fridge and freezer.

A big question is price. These homes need to be affordable but no one can tell me how much they cost to build or how much they would sell for. The closest I get is learning that one of the builders said he could build a zero-carbon home for roughly £135,000. These prototypes have cost more because they are designed to showcase different technologies.

In the energy centre, an offsite control room that houses different renewable technologies that provide hot water and heating for the ten homes, there are five different methods being trialled. These include a wood-chip biomass boiler and a hydrogen fuel cell; you would normally require only one.

Everything here is set up for living more closely within a community. From the shared car and garden to the energy centre, there is little chance of escaping your neighbours, although some residents seem to be trying their best to live as privately as possible.

Southern Electric has another motive. The two-year research project will also reveal how electricity companies might operate in a zero-carbon future. Quite rightly, providers are wondering about their role. What needs will they fulfil when solar panels and snazzy heat pumps do all the work?

That’s not to say that this is a cynical scheme to ensure electricity providers are kept in pocket. The project is one of the first to produce a detailed study of what it’s like to live in a zero-carbon house, plus there will be published research on energy management, conducted by a researcher from Reading University who is living in one of the houses with his family.

The best thing is that pioneering technology has been incorporated into modest, affordable housing. These are not elitist eco-palaces, nor do they offer Swampy-style living with compost loos. If as much care is given to all the zero-carbon homes rolled out after 2016, I’ll be the first in the queue. So long as it’s not near Slough.

This article first appeared in The Times on 21st March 2011