A new way to overcome the challenges of building renewables on significant and extreme weather-prone places has been successfully trialled on a hydroelectric scheme by the National Trust.

The conservation charity has switched-on a hydro turbine at Hafod y Porth in Snowdonia – the Trust’s first hydro turbine to be pre-fabricated off site before being transferred and assembled on location.

The switch-on marked the successful completion of the third project in the £3.5million pilot phase of the charity’s ambitious Renewable Energy Investment (REI) Programme, launched last year in conjunction with the renewable electricity supplier Good Energy.

In another first for the charity, the team developing the Hafod y Porth hydro are working with researchers from the Hydro-BPT project at Bangor University to calculate the carbon footprint of the installation and expect it to balance its energy investment in less than a year of being in operation.

“We do get a lot of unpredictably wet weather in Snowdonia," said Keith Jones, National Trust Environmental Practices Advisor. "This can be great when the hydro is in, but it’s not ideal for construction – a couple of flash floods can wash away days of hard work. By pre-fabricating components off site we’re removing a lot of these risks, reducing our carbon footprint and driving down our overall costs."

Building the hydro components off site also gave the team a greater level of control over the installation of the weir which has been sensitively crafted into the historic landscape near to Dinas Emrys, a scheduled ancient monument and legendary birthplace of Wales’ national emblem, the Red Dragon.

The hydro scheme which has a capacity of just under 100kW cost £550,000 and has an anticipated payback of around six years. All electricity generated will be sold via the Grid to Good Energy.

Other pilot projects in the Trust’s REI programme that have now been completed are an award winning 300kW marine source heat pump – the biggest in Britain – at Plas Newydd on Anglesey and a 199kW biomass boiler at Croft Castle in Herefordshire. The remaining two schemes, a 100kW hydro turbine at Sticklebarn Tavern in Great Langdale and a 199kW biomass boiler at Ickworth in Suffolk, will be launched early next year.

If the pilot phase is successful, the Trust is expected to spend ten times that amount on 43 renewable energy projects, which will help the charity to meet its targets to halve fossil fuel use and generate 50 per cent of its energy from renewable sources by 2020. It will also save the charity around £4million each year, to fund more conservation projects. A decision on the full REI programme is likely to be made in Spring 2015.

Image: The National Trust’s Hafod y Porth hydro project (Keith Jones)