Snowdonia Pumped Hydro, which intends to build a 600 MWh pumped electricity storage facility at Glyn Rhonwy near Llanberis under planning approval granted in late 2013, is applying to increase the output of the facility from 49.9 MW to 99.9 MW.
The proposed change in output would be achieved by increasing the capacity of the underground turbines and associated equipment. In every other respect the revised facility would remain identical to that already approved.
The decision to apply for the change has been reached following talks with the UK government's Department of Energy and Climate Change, and construction company partners. Britain's energy needs have evolved since the scheme was designed and the government has included storage within the 2014 Electricity Market Reform Act with the aim of helping to ensure that Britain does not suffer blackouts.
The higher output will enable the Glyn Rhonwy facility to play a greater role in the new market, making it more useful in balancing supply and demand as the percentage of renewables supplying power to the UK's electricity grid continues to increase. The facility is expected to achieve carbon payback in around six months. Construction work is due to begin at the site next year.
"The capacity of the facility would remain 600 MWh, the overall footprint of the site would stay the same, the reservoirs and dams would remain the same, the pipe that connects the two reservoirs would be the same size and remain buried, and the plant house on the Glyn Rhonwy industrial park would also remain the same size" commented SPH managing director Dave Holmes. "To achieve the increase in output we would simply install larger turbines and associated equipment underground. It's therefore hugely frustrating for us, and for all the stakeholders consulted as part of the original planning process, that we have to go around the block again.
"However, we're doing it because with the change in the UK's energy landscape as a result of the creation of the Capacity Market the gains from the uplift in output both for the scheme, and for the local community, are overwhelmingly positive."
Raising the output of the facility to 99.9MW would be expected to generate rates payments to Gwynedd Council of approximately £600 000 a year. In addition, QBC has pledged to establish an independent trust to manage community contributions from the facility, including an initial grant of £325 000 and annual payments of £15 000.