There was one in every parish, or, all I want for Christmas is a Siemens SWT-6.0

Posted on: December 2nd, 2011 by Andrew Syvret No Comments

St Ouen's Mill and Church from Les Blanches Banques…

In time honoured tradition, as is often the Jersey way, this post was conceived on the back of an envelope, on Friday. It is offered purely as an encouragement to think about the future of renewable energy in our region.


Earlier this week German industrial giant Siemens AG formally launched a new direct drive 6 megawatt wind turbine. Designed specifically for installation in challenging offshore locations, Siemens “expect the SWT-6.0 turbine to become the new standard for offshore wind power projects around the globe”. An informative article describing these massive 'engines' can be found on Sustainable Guernsey.

To put 6 megawatts in perspective, the back of our envelope tells us:

Jersey peak winter electricity demand = 158MW

Typical minimum summer demand = 36MW

On the basis of a reasonable 10MW potential installed generating capacity per km² of seabed, a notional 160MW facility would require the development of roughly 16km² or 0.8% of Jersey's +2000km² Crown owned territorial sea, using 27 Siemens SWT-6.0's, for example.


To look at this area in another way, consider the fact that Jersey currently has the following Ramsar Wetlands of International Importance:

SE Coast of Jersey (2001) ~ 3202 hectares
Les Écréhous & Les Dirouilles (2005) ~ 5459 hectares
Les Minquiers (2005) ~ 9575 hectares
Les Pierres de Lecq (Paternosters) (2005) ~ 512 hectares
TOTAL ~ 18748 hectares = 187.5 km²

16km² represents 8.5% of the 187.5 km² currently 'protected' under the Ramsar Convention. One 6MW turbine could supply sufficient energy to service a pilot electric vehicle scheme or some similar green initiative, for example. The construction of a single new 'windmill' would provide a welcome boost to the local economy. If we might face Normandy windfarms in the foreseeable future whether we like them or not, we may as well see our own community owned generating capacity when we gaze out to sea, non?


Beyond our waters, to scale our 158 megawatt peak demand, on 29 November 2011 the European Wind Energy Association published a report Wind In Our Sails, detailing the outlook for European windpower. Some 141 gigawatts (GW) of offshore wind energy capacity is built, under construction, consented, or planned in Europe: enough to power 130 million average EU households. 1GW=1000MW.

The experimental hydrolienne or marine current turbine recently installed near Paimpol in Brittany, presently the largest in the world and the subject of a previous post, has a generating capacity of 0.5MW. Jersey's turbulent shallow seas are in fact far from ideal for this technology and current velocities are considered 'marginal'. Engineering will improve, but one must be realistic about prospects.


There is of course no one (1) future green energy solution. Some days there is simply no wind, tidal flows are not constant. Solar can make a significant contribution. Reliable French connections will remain essential and may well afford us the opportunity to usefully sell electricity in times of surplus. It is believed there has been a mill here for six hundred years or more. The present structure was bought by the States of Jersey in October 1911 for £100, to be looked after by the Harbours Committee. The top section is German.

'Blue sky thinking' never did anyone any harm, did it? ;)  09:29:52 GMT…

À bétôt!