Trawsdir is a 5* family-run and maintained touring and caravan park located in Snowdonia National Park in an area of outstanding natural beauty overlooking both Cardigan Bay and the impressive Lleyn Peninsula. The owners of the park were looking for the ways of reducing overall running costs of the toilet / shower block as well as attracting visitors on the basis of being 'green', eco caravan and camping site.
During recent refurbishment work at the park, local renewable energy installers Arizon Energy, were asked to review options for renewable energy technology, determining the cost/benefit of a number of alternatives including solar thermal and solar PV.
Initial analysis by Arizon highlighted that the demand for hot water within the shower block was consuming a considerable proportion of the overall energy usage of the park, particularly in the peak summer months, and suggested installation of solar thermal panels to help meet this demand in an environmentally friendly way.
Arizon approached Kingspan Solar, part of Kingspan Environmental, to help design a system to provide a reliable source of year-round hot water for the block that could also cope with the heavy seasonal loading placed upon it during peak periods.
Kingspan Solar’s specialist design and engineering team designed a dual-purpose solar thermal system that not only heated the domestic potable water for the showers and basins within the block, but also, the excess energy it generated supplied additional hot water to an underfloor heating system to help dry the shower floors and prevent damp and mould developing.
The designers gathered pertinent information surrounding the installation, such as floor areas and the flow temperature required to feed both systems, as well as the amount of water used each day, and this was fed into Kingspan Solar software. The software calculates the metre2 of solar thermal collectors and their optimum placement on the shower block’s roof to maximise solar collection both during the morning and in the period of peak energy demand in the evening. Highly accurate annual daily water usage figures were obtained from metre readings at the park, which added extra precision to their calculations and confidence in the efficacy and efficiency of the system design.
In total, 10 Thermomax Heat Pipe solar thermal collectors were specified covering 28sqm, to be placed West/East on each side of the shower block – with the majority facing West with the tubes twisted towards south to capture the early afternoon /evening sun to deliver sufficient energy to cover the additional hot water loading later in the day. The Thermomax collectors with dual stream pumps fed heated Glycol to two x 500l Manco stainless steel cylinders and one x 500l Manco stainless steel buffer to the underfloor heating.
During the winter months, the solar thermal system has been designed to continue to feed warmed water into the underfloor heating as a defence against frozen and burst pipes and to continue to resist the build-up of mould.
A year on from the original installation it is clear that the system is out-performing every expectation. Results collated by Arizon have showed enormous energy savings, far outstripping the initial T*SOL predictions.
The system has generated 14,994kWh of heat which equates to annual commercial RHI income in excess of £1,300. Annual saving in LPG usage for hot water only, as a consequence of the installation, equates to more than £770; add to that the further savings from the solar heated underfloor heating system equating to £1882 pa and in total the system is boosting the income generated by the park by over £3,000 per annum!
Chris Shenton who co-owns the park with Rob Williams says: "The system that was installed has met and exceeded our and the installer's expectations.
“The savings in gas alone speak for themselves; having the added benefit of the RHI makes the payback of the system even sooner.
“With the cost of fossil fuels rising annually we are hoping to be saving well into the future, making us a greener site and reducing our carbon footprint.
“We would recommend that all sites like ourselves large or small benefit from renewable energy.”