With the promise of yet more increas­es in the cost of energy looming, harnessing the power of nature is no longer the sole provision of the anorak brigade. The eco-friendly solutions to heating and lighting provided by modern 'green' houses can save a small fortune but – and there's always a 'but' – there are significant costs involved in installing some of these less conventional features.


Emma Jane Hoey's charming house – which she shares with husband John and their two children – sits on an elevated site in the Co Monaghan countryside and was completed two years ago. As well as wanting a green home, Emma Jane admits she has something of a Little House on the Prairie obsession and so went the whole hog – or in this case, the whole log – and came up with the idea of a wood cabin.


The cost of building came in just under €250,000, but with an additional cost of roughly €20,000 for solar panels and a wood-burning stove. On a project starting from scratch, it's simpler and more cost-effective to incorporate eco-friendly measures right from the start, rather than trying to 'green-up' an older property, although in this instance, Emma Jane had the solar panels installed post-build.


The family has been in the house just two years but already Emma Jane feels the minuscule energy bills more than compensate for the additional five-figure outlay. The total heating costs for last year came to €150 – and Emma Jane says that would have been even lower if she and John hadn't been too lazy to gather sticks and chop logs.


Electricity averages around €100 for every two-monthly bill, while a tank of gas for the cooker, which lasts the entire year, is around €25. "We just recently recycled our electric kettle and bought a whistling one for the stove instead as it's much more economical." Their total energy bills last year came in at well under €1,000.


Good Wood Solutions were the company of choice for the construction as they use solid logs throughout, unlike many others who substitute laminate on the interior walls, says Emma Jane.


The elevated location, although windy, is also key to the success of this project – the house takes full advantage of its southfacing orientation. Extensive glazing on the southern walls allows maximum solar gain directly into the open-plan kitchen, living room and rooms beyond. Bedrooms face east so the family wake up to sunshine.


"There are east-facing windows in the kitchen too and then, at around midday, the sun hits the front of the house and the natural warmth flows throughout. We didn't put windows on the north of the house and so all of the benefit of the sun is contained."


Construction took four months and the family moved in during spring 2006. Emma Jane's thorough approach to research on solar passive design and, just as importantly, getting a full understanding on how different features would work, was crucial to the project. The solar panels are what are referred to as a 'retro-fit' – they are installed on an existing structure not incorporated in a new build.


"When I was researching solar panels, for example, it took me quite a while to get a handle on how they actually worked. I approached a couple of companies initially and found they couldn't explain the system in operation clearly. I also didn't like the idea of fitting solar panels as the house was being constructed because of uncertainty as to how they would work in the overall scheme. But later on, I contacted Gavin Solar in Cavan, and he was able to demonstrate the system in a straightforward manner and we really liked the idea – although the design we chose wasn't actually covered by the grant offered at the time."


The panels in the house are solely powered by the sun, although many other designs have a degree of electrical connectivity. Having said that, all solar panels must have a circulation pump run by electricity, says Hoey, so there is still a degree of dependency on the ESB.


"We have bubbling hot water all through summer from the solar panels, while we don't have a central heating system at all. The wood-burning stove isn't lit until December. This year, we had to turn if off again in the second week in February – the rooms were just too hot."


The cost of the stove and the panels may sound pricey but Emma Jane says the outlay is recouped by the minimal energy bills – particularly as costs are set to soar again next winter.


She is also involv­ed in a forest planting scheme with her father who lives nearby, ensuring a plentiful supply of fuel for the stove. Not that she is wanting for the moment – those wood off-cuts and logs left over from the construction of the house are keeping the home fires burning nicely on the rare occasion they are needed.


Meanwhile, the vegetable plot is a current passion in the family's quest for the self-sufficient good life, but it seems even the greenest project sprouts its nuisances too: "The vegetables are great – but unfortunately the dandelions are thriving too!"