In an age obsessed with environmental sustainability, Tony Wrench and his partner Jane Faith would appear to be beyond reproach.

Their eco-home was made with local materials, its electricity supplied by solar and wind power and its heat kept in by a turf roof and straw insulation. They compost their sewage using a reed bed and make do without a fridge or washing machine.

But the couple have been told to demolish their beloved home - because it isn’t green enough.

The single-room roundhouse, based on a Celtic layout, is set in a protected part of the Pembrokeshire coast and has been refused planning permission because it “failed to make a positive environmental impact”. The couple, who grow their own food and make a modest living from music and woodcraft, feel they are being victimised despite doing more than most to reduce their carbon footprint.

The Hobbit House, as locals in Brithdir Mawr, near Newport, have dubbed it, is destined for demolition unless given a last-minute reprieve by the Welsh Assembly.

“You get the feeling that it does not matter what you do, they will always say ‘no’,” Mr Wrench said.

“We are doing everything we possibly can to reduce our carbon footprint. It is about as low as we can get and it demonstrates that an environmentally sustainable lifestyle is possible.”

He added: “This house is so beautiful to be in, and the garden so fruitful and bursting with life of all kinds, that I still cannot believe that in a world of such environmental spoilation and with spreading patches of such ugliness, there are still people paid to work on having this home demolished. What low impact proposal will ever withstand this level of nit-picking?” said Mr Wrench, a wood turner.

The Pembrokeshire Coast National Park Authority ruled that the dwelling would have a negative impact on dormice, bats and invertebrates. An ecologist’s report concluded that if permission were granted, the home would cause, “severe degradation of the National Park landscape”.

Mr Wrench, 61, plans to appeal against the decision, the latest step in a ten-year legal battle.

He spent £3,000 building the home a decade ago using local materials and insulating it with straw. A study confirmed that their carbon footprint was just a fraction of the national average, but the park authority says that is still not good enough.

Ifor Jones, the authority’s head of conservation, admitted that the rules were strict, but said that they applied to everyone. He said: “Yes, we do have high hurdles, but it is important that any development enhances the environment, rather than detracts from it. In this instance the location of the roundhouse and vegetable garden within an area of semi-natural vegetation, comprising woodland edge and unimproved wet grassland, is considered to have had negative impacts.”

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