Friday, 26 March 2010


The company responsible for maintaining the electricity transmission infrastructure in Scotland, SHETL, has unveiled its plans for linking the so-called interconnector to the island grid. This will involve a high-voltage (132 kilovolt) powerline from the Creed River substation to the Arnish Fabrication Yard, thence by subsea cable to a large electricity substation, to be built at Gravir in South Lochs. That is the point where electricity, generated by landbased renewable energy projects in Lewis (e.g. the Eishken Windfarm, the Shader Tidal Barrage and various community windfarms) will be transmitted to the mainland using the interconnector. This subsea cable will link from Little Loch Broom to Beauly (near Inverness), and onwards to Denny in Stirlingshire using the upgraded high-voltage link across the Highlands.

This is all subject to approval by the Scottish Government of the Interconnector and the Arnish to Gravir subsea cable. The project is cited as necessary to pipe all the power, generated by renewable projects, away to the mainland.

A few weeks ago, it was reported that a weather pattern was in place one day which created flat calm conditions across Scotland. All the windfarms in the country, from the Borders to the Northern Isles, only managed to generate enough power that day to boil 1,000 kettles. That would have left an awful lot of folk with cold cups of tea. And we're supposed to rely on that for all our power? Just as well a new tranche of renewable energy project was released this week, related to tidal and wave power in the Pentland Firth, between Orkney and Caithness.


  1. Hullo Arnish, yes the Big Calm was certainly a big stick in the eye of those who advocate reliance on massive wind-generated electricity. Another jolt was provided by the recent UK govt. report on the overall efficiency of wind power generation, which turns out to be pathertically low. I have long awaited a report of this kind, or even better, a report that would show the net energy balance taking into account the energy costs of making, erecting, servicing and removing wind turbines. While waiting for this, my gut feeling is that small-scale wind parks can probably provide an environmental benefit. However, here in Sweden the power companies have a price structure that doesn't make selling them surplus energy commercially interesting. The growth of wind farms in Sweden is entirely "fuelled" by govt. subsidies.
    Only when it will be possible to run a steel mill or a paper mill on green energy have we arrived in a new paradigm for the globe. That is why I expect tidal power to be a better option than wind power, because tides are predictable. Unfortunately when one looks at the global distribution of tidal ranges it turns out that most coasts have very moderate tidal ranges. The only heavily industrialised regions with large tidal ranges are NW Europe, parts of the Eastern seaboard of North America and parts of Japan. The cost of servicing underwater units is also likely to be high.
    What is the logic behind bringing power generated in the Outer Hebrides ashore at Beauly on the East coast?

  2. Last week when it was very windy I noticed that the Whitelee wind farm near here was stationary - the wind must have been too strong. Not even one cup of tea's worth of power that day.

  3. "And we’re supposed to rely on that for all our power?"

    No, that would be silly.

    To aid a transition from coal to clean energy however, yes.