After almost 40 years when no new pump storage hydro (PSH) schemes were developed in the UK, there is now a gold rush by developers seeking new sites. The switch from fossil fuels to renewables, which tend to produce power more intermittently, means more long-duration energy storage is required. Portrayed in mainstream media as a novel solution to generation intermittency, this mature form of energy storage is now finding a new, global, lease of life.
Climate change is the greatest threat to our native biodiversity, including wild salmon, and we are fully supportive of the de-carbonisation of the national grid. However, while we are not against PSH per se, we strongly believe that such projects should be located where the environmental risks are lowest. Pump storage, until now, has had a free ride regarding its environmental impact, with politicians pictured on location and glossy videos extolling its virtues. A recent report by Scottish Renewables didn’t mention environmental concerns.
Pump storage hydro explained
So, what is pump storage hydro? The term water battery is sometimes used, as low demand and inexpensive electricity is used to pump water uphill into an upper reservoir, charging the battery, usually overnight. When demand for energy increases and the price rises, the valves are opened and the stored water flows back down the tunnel, through the reversible turbines, generating valuable electricity this time. Daily movements in the spot price for electricity can be extreme, from up to £2000/MWh to as little as £30-40/MWh. Even though it requires more energy to pump water uphill, substantial economic gains await.
This is an important point; pump storage – classed as ‘non-renewable hydro’ – consumes more energy than it generates. Storage is its key function. Perhaps this explains the lack of interest in this form of energy management in recent decades, storage simply wasn’t required when we had all that fossil fuel to burn.
Pump storage at Loch Ness
Why are we, a local Salmon Fishery Board, so concerned that we are campaigning against the proliferation of pump storage on Loch Ness? Firstly, Loch Ness, famous amongst other things, for holding the greatest volume of water in Scotland, is in demand for PSH schemes. Foyers PSH was commissioned in 1974, the Red John PSH scheme was granted planning permission in 2021, and in November 2023, the planning application for the proposed Loch Kemp scheme was submitted. After a long delay, the rights to develop Red John were sold to Statkraft, a Norwegian state-owned energy company at the end of 2023. Its deep pockets will ensure that this small and apparently expensive scheme will be built. The proposed Loch Kemp scheme has four times the storage capacity of Foyers or Red John. Of particular concern is the cumulative impact of these multiple schemes on the ecology of Loch Ness.
What are the environmental risks of pump storage? Our concerns relate to PSH’s impact on wild salmon smolts (juvenile salmon as they leave the natal rivers and migrate to sea) migration through lochs, (where there is currently a huge knowledge gap) and on the temperature and hydrology of Loch Ness. We are also concerned about the impact that significant, rapid water level changes (up to 73 cm daily, according to the Kemp planning documents) will have on shoreline ecology and River Ness flows; as well as the wider ecosystem impacts.
Atlantic salmon are fundamental part of the ecology of the Highlands
Atlantic salmon are in decline across their range, with the UK population recently classed as endangered by the IUCN. The salmon rod catch in the Ness system in 2023 was the lowest on record. This has more than just an impact on salmon anglers. Atlantic salmon, that iconic species, are a fundamental part of the ecology of the Highlands.
At Chanonry Point, a spectacular natural narrowing of the Moray Firth close to Inverness, is the scene of the greatest wildlife spectacle in the Highlands. On an incoming tide, bottlenose dolphins patrol the shallows at the point, ambushing and eating salmon as they return to the River Ness. In the summer, large crowds gather in anticipation of this unique spectacle with large dolphins feeding within metres of the shore. There can be few more obvious examples of an ecosystem in action than this link between river, loch and the sea.
Summer months in Loch Ness: not enough water to allow pump storage
Of course, this is Loch Ness, one of the top three tourist destinations in Scotland, so there are wider concerns aside from purely ecological. Our analysis shows that, during the summer months there is simply not enough water resource available in Loch Ness to allow three pump storage schemes, which pump huge volumes of water, to generate at full capacity.
There are many other sectors reliant on water levels in Loch Ness, including commercial cruise boat operators, recreational craft, Caledonian Canal traffic and rescue boats. There is a legally agreed minimum loch level between SSE (Foyers PSH) and Scottish Canals to ensure safe navigation. In May 2023, the loch fell to a record low level, below the navigational limit. Speculation regarding the role of PSH in this continues unabated. What we can be sure of is that if Loch Kemp gets planning approval Loch Ness will be at minimum levels much more often, almost daily during the summer, affecting all other users of the loch.
PSH sector still has work to do to understand its impact
Quite what the most famous inhabitant of the great loch will make of the cumulative impact on the natural, seasonally driven hydrology of the loch, or its famed stable temperature regime remains to be seen. In that regard we are all in the same boat, the research simply hasn’t been done. The PSH sector has a lot of work to do to understand its impact. Perhaps this is understandable given the lack of interest in this technology in recent decades.
We are actively campaigning against any further PSH schemes on Loch Ness, until further research is completed and the PSH sector can prove that its activities are as environmentally benign as claimed. Ness DSFB commissioned the Norwegian Institute for Nature Research (NINA) to produce a report on PSH’s impact on Loch Ness. This was received in August 2023 and now guides the board’s response to PSH. In the meantime, we are asking the Scottish Government to produce clear guidance to ensure that the sector only develops in the most appropriate and least damaging locations.
Please sign our petition and submit objections here.
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