The white building at the right of the picture is Loch Striven hydroelectric power station. It generates a maximum of 8 MW – not continuously, but for a few hours most days. It’s very quiet, and unobtrusive in the landscape – about the size and general appearance of a large house. The penstocks (pipes) carrying the water to it are more obtrusive, but not really very objectionable. They could have been buried, but would it be worth it?
A hydroelectric scheme like this could be fairly easily converted to a pumped storage scheme. You’d need a dual-purpose pump/turbine, and it would be housed in an excavated hole below low tide level. Using the existing grid connections, you could store 8 MW whenever supply from renewable sources exceeded demand by at least that much; and supply 8 MW continuously for over two weeks from full to empty. Alternatively, you could upgrade the grid connection, and instal larger pump/turbines; you could then store energy at a higher rate, and return it to the grid at a higher rate, but for a shorter period.
This particular location would need the turbines, pumps and penstocks to be designed for salt water, and Loch Tarsan would become brackish or even salty. It would be a change in the environment. Some species would suffer; others would gain. Would the change constitute an environmental disaster? I very much doubt it, by any objective standard.
The construction of the dams for Loch Tarsan were significant costs, and Loch Tarsan itself was a significant change in the environment. Whether that change constituted environmental damage I’m not sure. The environment there is not unattractive now.
©Clive K Semmens 2017