TN 01. August 2022 Edition No. 1
Cwtch cabins, an off grid campsite enterprise, relies on generating all electricity and heat on site.
They use solar thermal, solar PV and biomass to heat the water for the showers and basins (yes, they have hot showers). Their cabins or shepherd huts come with their own solar PV set to charge phones and lanterns and has lighting fixed inside.
Their ethos of having a low impact on the environment and been completely sustainable, fits perfectly with a biomass boiler installation.
Their requirement to heat their own home as well as hot showers and domestic hot water for 40 people twice a day at the campsite meant that a HDG K33 pellet boiler was an ideal fit for the job. As it has an automated fuel delivery system, it can turn itself on and off automatically as the demand for hot water is needed.
The system was designed with a large 3000 litre thermal store along with the 33kW pellet boiler in the boiler house on the campsite, with a district heating circuit to the house, where a 1000 litre thermal buffer stores the heat needed for the house. The system also uses solar thermal panels connected to the large buffer collecting free hot water in the summer months. The main reason for the extra 1000 litre buffer in the house was that in winter, when the campsite is not in use, the boiler can be switched to just heat the small buffer in the house, bypassing the larger 3000 litre buffer completely. In the summer when the campsite is in use the house will draw its heat from the 3000 litre buffer and transfer it to its smaller buffer.
This ability to split the heating circuits between summer and winter means a massive saving in energy and fuel costs and also allows for easy expansion to cover the high demand for showers in the summer, all utilising the same heat source of the biomass boiler and solar thermal panels.