Paul and I spent the last couple of days with NT Directors discussing how the approaches taken in NT Wales can be used across the National Trust in terms of our environmental management approach but also our stepped approach to renewables deployment.
The weather was superb and looking over the Menai Straits yesterday at the potential heat pump and then up Snowdon today to look at the hydro development site was a nice way to end the week. On the way back home took we took a detour and stopped to have a look at the work at Bwlch Mwlchan buildings on the shores of Llyn Gwynant. This is a complete overhaul of a set of agricultural buildings once used as a mountain activity centre but now about to enter a new phase. The NT is working with Plumpton Collage to develop an education residential centre for the college at the site. My involvement has been with the NT building surveyor to look at the energy, water and waste aspects. We had a grandiose plan to harvest heat from the lake with a heat pump but the site has a miniscule electricity supply and so we have gone for a mix and match approach. Firstly insulate to the max and then background heat with a small air source heat pump and top up with a multi fuel stove and some LPG for the cooking. This will be supplemented with some PV on the roof as well as a solar thermal system. Things are moving quickly here
The second piece of work today was a request to advise on timber yields and storage required for a farm the NT are restoring / improving / conserving in Pembrokeshire. The NT is installing a new Windhager gasifying log boiler to supply hot water and heat for the farmhouse. Part of this work is to look at how much of the land we need to dedicate for growing the fuel, how much storage and so on. So it’s not a case of install the biomass and then figure out where to get the timber. This is one of those virtuous circle ones. Lets grow what we need but first lower the load by efficiency measures at the farm. So it’s 1 tonne of timber at 25% moisture = 2.5m3 ish = 4000kwh (ish) For this farm-house we might need to store up to 40m3 of logs for two years of supply – which means we need a certain size of barn to house all of this timber and a certain amount of land for a sustainable yield to supply the log boiler. Joined up thinking is nice to see in practice!