WHEN the Germany-based group Germans for Scottish Independence set the date for their independence march in Berlin last weekend, they seemed to have overlooked that the German elections were only three weeks away.

In fact, they chose the day before a key debate between Angela Merkel and her challenger, the former EU parliament president Martin Schulz, which was broadcast nationwide by the four biggest TV channels.

Not ideal for raising awareness of a cause which the German public might find a bit distant in the circumstances.

Since I am in Germany at the moment, I checked the main news media as well as the local Berlin headlines for any coverage of the Yes march but found nothing.

Maybe Germans for Scottish Independence need to try harder next time to live up to the reputation so often associated with the German national character: being organised.

Regina Erich

THE Tories intend to use the Statute of Proclamations to enable them to by-pass Parliament and bulldoze through measures relating to Brexit.

I would be grateful if anyone can explain to me how this can be imposed on Scotland since Henry VIII was never King of Scots. How can legislation which pre-dates both the Union of the Crowns in 1603 and the Union of the Parliaments in 1707 be used to impose laws on Scotland?

Sandra Durning

REGARDING the plan for a tennis and golf centre at Park of Keir, near Dunblane, Judy Murray is keen that her sons have a lasting legacy.

I think the greatest legacy the family could leave would be to fund the reopening of hundreds of public tennis courts which local councils cannot afford to maintain or to staff. Only by doing this will tennis begin to be available to ordinary young people, with a spin-off of reducing boredom and the associated poor behaviour which young people can involve themselves in.

For our Scottish Government to support this planning application does to address inequality in Scotland. This vanity project is a poor idea and in the wrong location.

Aileen Park

ROY Pedersen wrote an excellent letter about marine renewables (The National, September 4). We really do have the opportunity for an industrial, economic, social and environmental renaissance in Scotland. All we need is the will and vision to make it happen.

Jon Southerington

Deerness, Orkney

I SHARE your correspondent Roy Pedersen’s enthusiasm for tidal stream generation as its predictability makes it stand out from other forms of renewable generation. I would, however, like to make two points.

Firstly, generated power varies as the cube of the stream velocity. While Mr Pedersen is correct that deploying turbines in different locations will give a degree of smoothing of total power output on any one day, a significant omission is consideration of the roughly 14-day tidal cycle between springs and neaps which affects all locations.

The spring velocity is typically twice the neap velocity, so, while predictable, tidal cannot be described as a constant power source.

Secondly, even if electrolysis is 100 per cent efficient (it isn’t), burning the resulting hydrogen in a spark ignition internal combustion engine would deliver about 25 per cent efficiency.

Using generated electricity to instead charge battery-powered vehicles would give a cycle efficiency of 80 per cent or better.

David Simpson
Address supplied

THANK you for publishing my letter in yesterday’s National. Just one small, but important, point – it is “tidal stream” not “wave” power that could be the key to making the case for indy.

Tidal stream power, if drawn from multiple locations, is constant and predictable; wave power, like wind is intermittent and unpredictable. I hope you don’t mind me drawing this to your attention.

Roy Pedersen