Could Penrhyn become the greenest castle in Wales?

From June 2016 Penrhyn Castle will take the first steps in waving a final goodbye to oil fuelled mansions in Wales, by breaking ground on a new Biomass Energy Project.

The team have set to work on building a new boiler house and woodchip storage facility in preparation of replacing the old oil fuelled system with a new biomass renewable heating system to heat the vast castle rooms by September 2016.

Penrhyn is the last National Trust mansion to use oil fuel in its heating system; therefore this project will also see an end to oil powered systems of its kind anywhere in Wales.

It's not just posh plates and intricate plasterwork. We do sometimes need to get a bit industrial! Work begins on laying the pipes from the boiler up to the castle heating system.
Work begins to install the pipes from the boiler up to the castle heating system.

Elgan Roberts, Renewable Energy Project Manager, explains why this project is so important to the National Trust and Penrhyn Castle:

“Penrhyn Castle is a huge property, the largest in Wales and the third most expensive to keep in the whole of the National Trust so finding more efficient, environmentally sound and cost effective ways of heating is essential to safeguarding the property as we look to the future.

Financial benefits

“This project will not only have an obvious environmental impact, saving 80 tonnes of CO2 emissions per year and contributing to National Trust’s target of sourcing 50% of its energy from renewables by 2020, but it will directly benefit the property financially in terms of operational costs,

" Once the [Biomass] system goes live in September, the property will be able to redirect saved funds directly into its core conservation work; looking after this special place, forever, for everyone!"
- Elgan Roberts, Renewable Energy Project Manage

The boiler will use locally sourced woodchip and woodchip harvested from their own woodlands, in-line with their woodland management policy, to heat the Castle.

This will become part of a larger project  which has already seen the installation of half an acre of solar panels, nearly a thousand LED light bulbs, and 7000m2 of loft insulation in previous years.

As well as saving money and  reducing CO2 emissions; the project will also reduce the risks associated with oil storage by removing 4 large oil tanks currently housed within the property.

Work begins on preparing the site for Penrhyn Castle's new biomass boiler.
Work begins on the new site for Penrhyn Castle's biomass boiler.

Biomass boiler installation timeline:


  • Construct new boiler house and woodchip store in visitor car park
  • Dig trench and install heat main pipe up to castle


  • Install boiler and equipment in new building
  • Remove old oil boilers and install new pipe work in cellars


  • First delivery of woodchip
  • Commission and handover of new system


The project begins in June and the team hope to offer tours and talks on their project for visitors in the near future.