We are the UK’s first luxury sustainable holiday location.” That’s the BIG CLAIM of Natural Retreats, a young company with bright green plans for the future. It currently has nine cabins set in 54 pristine acres bordering the Yorkshire Dales. Each is a high-tech, high-spec dwelling that sleeps up to six from as little as £125 per night. It will add more over the coming months, and aims to roll out the model to other national parks. Loch Lomond and Snowdonia are next on the list.

It’s the sort of pitch that would do well on Dragons’ Den. It’s top-end, it’s trendy and, of course, it has that all-new, all-important phrase for investors... it’s environmentally friendly.

But what’s it like for guests? I took over Cabin Three for a couple of days last week to find out, and I brought my eco-obsessed family with me.

On the train up (because you can’t drive to Britain’s first sustainable luxury holiday location, can you?), we imagined the green thrills that lay in store: solar-powered TV, wind-powered washing machine, mouse-propelled air-con and the latest in sewage recycling. How nice to think that our organically reared poo would contribute to the building materials for the next nine cabins. Or some such.

Then we arrived, and immediately became suspicious. As Ian, the affable site manager, welcomed us warmly, my eyes lit up at the sight of a 3,000in LCD TV, only to be snuffed out again by a disapproving shake of Eco-Harriet’s head. Because the TV was on, playing soft classical music. And the lights were on, too: lots of them, in the bedrooms and bathrooms, despite it being the middle of the day. Even big, planet-eating hotel chains are working out that leaving lots of things on is a nono.

Ian explained that the electricity was not produced on site, but came from renewable sources. What, no solar panels? No: they weren’t given planning permission, so the roofs are made of grass instead. The cabins are supplied by spring water from the surrounding hills, but there’s no clever system to reuse grey water. And my poo won’t be making wattlish bricks – it just goes into a cesspit. What a waste.

Our cabin is unquestionably luxurious, in a sort of Ideal-Homes-Exhibition-in-a-Scandinavian-forest way: the side with the view of a pond, some woods and the distant, glorious dales is all glass – which, in estate-agent parlance, brings the outside in. And the glass is very clever: it lets in only a third of the heat during the day, so everyone doesn’t bake like a dog in a car at the supermarket. But it keeps it in for the night, so you rarely need to use heating. Even in Yorkshire.

It is the best-equipped self-catering property I’ve stayed at in a long time: nice dishwasher (sparking an “Are dishwashers eco?” debate), bespoke marble kitchen island, full sets of matching, crack-free crockery, a microwave (tsk, tsk), a lovely log stove and a DVD player. Frankly, it’s a lot more than you’d expect from a log cabin. It’s the yuppie version, the Russian-oligarch version, with sheepskin cushions, leather sofas, mood lighting and cool, white, minimalist walls. But then, they haven’t just called themselves a luxury cabin park, have they? They’re using the words “first” and “sustainable”, as well.

Ian’s gone, and Eco-Harriet’s picking through the welcome hamper. It comes from the local grocer, but the orange juice is Tropicana, the apples are from New Zealand and only the tea bags appear to be organic. When I point out that the butter’s from Yorkshire, she just mutters that it’s not good enough. Ten minutes later, Ian returns with a highchair for Eco-Freddie and says – unprompted – that the hamper will be entirely organic from next week. He clearly has our cabin bugged, but this is good news.

What isn’t is the lack of attention to sustainable detail. They promise to keep the outside lighting low-impact at night, so the badgers, rabbits, moorhens and wild deer can frolic in peace. Marvellous. So there’s a torch... but why couldn’t it have been a wind-up one? Or at least one with rechargeable batteries (rather than Asda disposable ones)? They have recycling bins for bottles, cans and paper, but there’s no compost for the guests’ vegetable waste. Ian drives a chunky 4WD pickup, which is a little more acceptable out here than it is in Chelsea, but not much – you’d think they’d have developed some sort of electric-car system.

A lot of the furniture, crockery and cutlery is from Ikea. Shouldn’t “Britain’s first luxury sustainable location” have furniture made out of recycled tyres and newspapers, crafted by local artisans?

We set off for a walk, and everything feels a bit better, because the location is just great. Our cabin is on the lower level, but the ones higher up are more secluded, more tucked away in the forest. And out through the valley on Ian’s favourite walk – a spectacular loop on and off the coast-to-coast path – all is well with the world. I could think of little more appealing than an airy designer cabin as a base for exploring the wild beauty of Britain’s national parks. But Natural Retreats needs to go a lot further to earn that BIG CLAIM. It has to be relentlessly ecofriendly.

Back home in my (unsustainable but I’m not saying it isn’t) house, I put this to one of the company directors. Having the TV on was “absolutely inexcusable”; they’re investigating the possibility of a water turbine; the 4WD contract was inherited, and the next one will be greener; local artisans will help to furnish new cabins; they will do composting now it’s been suggested; and there won’t be any more apples from New Zealand. Not ever.

It’s got off to a slow start on the sustainable front, but if you want a luxurious affordable break in the Yorkshire Dales, and you don’t mind a bit of green-wash with your cornflakes, this is the place for you. Or you could just rent a nice stone cottage in the hills like everybody else.

Matt Rudd travelled to Darlington as a guest of GNER (0845 722 5225, www.gner.co.uk), which has return fares from London from £22. Taxis to the retreat cost about £20 each way (call 01748 825112). Or just hang the environment and drive. You can book your cabin on 0161 242 2970 or at www.naturalretreats.com

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