Biomass District Heating | Portmeirion

Portmeirion Village

Portmeirion is one of Wales’ premier visitor attractions. It is an Italianate Village of great architectural significance, which welcomes around 225,000 visitors per year. It is also famous for being the setting for television show “The Prisoner”.


Portmeirion Ltd wanted to explore the opportunities for heating the whole village from a centralised biomass energy centre, but with no adverse affect to the delicate building fabric, architectural value and aesthetic quality of the buildings and grounds comprising the village.


Sustainable Energy was appointed to provide full detailed design, contractor selection, act as Principal Designer and Project Manager for implementation of the project. Sustainable Energy developed a detailed design for the biomass energy centre, the 1.75 km district heating network and the integration work required in each building in order to allow connection to the biomass heating network; this included specification of Heat Interface Units in a number of properties. Sustainable Energy then assisted the Portmeirion management team to procure the necessary equipment and services, and provided support throughout installation and commissioning of the biomass heat network and managed the RHI application process.


Portmeirion Ltd employed local companies, while Sustainable Energy acted in a supporting role, providing design and technical support to the contractors and site presence to oversee and ensure best practice was achieved. The Sustainable Energy solution comprises a centralised energy centre with 2 x 500 kW biomass woodchip boilers, and 35,000 litres of thermal storage. Two oil boilers are configured to supply back up and auxiliary heating. The energy centre distributes heat to two networks zones; one supplying the main Village comprising 26 buildings including the hotel; whilst a second network zone supplies the Castle and surrounding buildings.

The heat network consists of approximately 1.75 km of underground pre-insulated heating pipe. The network runs from the Castle at the north of the site, which is 50 m above sea level, to the hotel at the south of the site which is at sea level. Thus, it was critical to the success of this project to apply intelligent design of the distribution system and controls, to ensure efficient heat distribution throughout Portmeirion’s biomass heating network.