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Renewable energy at Tŷ Mawr Wybrnant

A stone farmhouse standing on a hillside above a low stone bridge.
Higher levels of rainfall are expected in the area around Tŷ Mawr Wybrnant in the future | © National Trust Images/Arnhel de Serra

Through collaboration with the Dwr Uisce Project – which includes researchers from Bangor University and Trinity College, Dublin – a renewable energy scheme has been installed at Tŷ Mawr Wybrnant in Conwy. The small ‘pico’ hydro-electric scheme will address damaging humidity levels, while at the same time helping with the National Trust’s aim to greatly reduce its consumption of fossil fuels.

Flooding at Tŷ Mawr Wybrnant

In spring 2019, Tŷ Mawr Wybrnant experienced its worst flood in living memory. The extra moisture in the air posed a threat to the unique collection of Bibles – including an original copy of the first Welsh Bible, printed in 1588 – on display at the 16th-century farmhouse, which meant more heating had to be used to reduce humidity levels. As a precaution, the core Bible collection was temporarily moved, with the 1588 Bible on display at Chirk Castle.

A sustainable energy scheme

The installation of a small ‘pico’ hydro-electric renewable energy scheme will help keep humidity levels to a minimum. In essence, water is actually helping to solve the problem it’s creating in the first place.

‘Climate predictions indicate likely increases in the severity and frequency of rainfall in the area. This small-scale technology is allowing us to adapt to future changes more sustainably.’

- Keith Jones, Climate Change Advisor for the National Trust

Visitors looking at a display case at Ty Mawr Wybrnant, birthplace of Bishop William Morgan in Conwy, Wales
Visitors looking at a display case at Ty Mawr Wybrnant | © National Trust Images / Arnhel de Serra

The Dwr Uisce Project

At Tŷ Mawr Wybrnant, we sought a more sustainable approach with help from the Dwr Uisce Project, which is supported through the Ireland-Wales Co-operation Programme 2014 (funded by the European Rural Development Fund) and includes researchers from Bangor University and Trinity College, Dublin. Having considered all the options for more efficient heating that is also sympathetic to a Grade II listed building, we opted for a 4.5kW hydro, known as a ‘pico’ hydro scheme, for its small size.

‘The hydro will only borrow a set percentage of the water from the stream once the water levels reach a certain point. This means we are generating the electricity when we most need it, when there’s more moisture in the air after rainfall. The energy is consumed directly on site, solely for the conservation of this priceless Bible collection.’

- Keith Jones, Climate Change Advisor for the National Trust

Turbine shed for pico hydro at Ty Mawr Wybrnant, Eryri
Turbine shed for pico hydro at Ty Mawr Wybrnant, Eryri | © National Trust Images

Environmental benefits

The long-term aim of the Dwr Uise Project, according to its lead Dr Aonghus McNabola, Associate Professor in Engineering at Trinity College, is to further develop the pico hydropower technology so it can be used more widely in the not-too-distant future and start benefiting the environment.

‘As well as the obvious financial savings, we expect a project like this to lead to greenhouse gas emission savings of just over 5.2 tons, per annum.’

- Dr Prysor Williams, team lead at Bangor University

Reducing our fossil-fuel use in Eryri (Snowdonia)

In a bid to halve our fossil-fuel consumption, we have installed several energy-efficient and renewable technologies across Eryri (Snowdonia) including biomass boilers, and heat pumps at farms, holiday cottages and offices. This is the eighth hydro-electric scheme we’ve installed in the area, the first of which was at Hafod y Llan and at 600kW was the largest.

Four visitors are walking outside beside a stone building at Ty Mawr Wybrnant, Conwy, with daisies and other wildflowers in the foreground.


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