North Sea Renewables Grid

Although critics of wind power suggest that wind is a variable energy source and can’t be relied upon to keep the lights on, this isn’t actually the case when wind power is distributed over a large area like the North Sea. Variations in production at one wind park can be partly balanced by that of another park several hundreds of kilometres away.

To demonstrate this concept, Greenpeace commissioned a report based on what would happen if real wind speeds over the North Sea were applied to more than 100 envisioned wind power projects with 10,000 turbines. If all projects from Belgium, Denmark, France, Germany, Great Britain, Netherlands and Norway were built there would be an installed capacity of 68.4Gw.

The top graph below shows how the power output of the propose London Array would fluctuate with changing wind speeds. When combined with all wind farms around the British east coast, the power production starts to level out as a dip in generation around London could be offset by heavy winds around Scotland. The final graph shows how wind production stabilises even more when combining all wind farm output from countries bordering the North Sea.

To capitalise on the balancing nature of distributed wind farms, a large North Sea grid spanning 3,850 miles would be required to connect all of the wind farms together. Such a grid would facilitate trade and increase security of supply by dispatching power from offshore wind farms to different countries depending on the highest demand. Moreover, an offshore grid allows the import of electricity from Norwegian hydro power plants to Britain and other countries. For some hydro plants, excess power (when the wind blows and sun shines) can even be used to pump water back into reservoirs, working like a huge water-battery. Biomass from European countries could also be fed into this grid.

A system of this nature with many thousands of wind turbines is more reliable, and energy production more secure because the impact of maintenance or defects will be negligible when compared to a large coal or nuclear plant going off line. Another advantage of a North Sea grid is that any future wave power, floating wind Turbines and tidal power stations could also be connected up to provide more power, stability and distribution of power between countries.

If this proposal were to be implemented then 70 million homes or 13% of the annual electricity consumption of the seven European countries could be met.

For the full report, see
http://www.greenpeace.de/fileadmin/gpd/user_upload/themen/energie/offshorewindgrid_final.pdf

Greenpeace Eco City

If a picture speaks a thousand words, a multimedia-packed, animation-filled interactive town must speak a million. Which is why Greenpeace have launched EfficienCity - to exlain exactly what decentralised energy is and how it works in practice (which can otherwise be a wordy business).

If you still believe the government and think we need nuclear power and coal to stop climate change, come and pay a visit to EfficienCity, which shows how pioneering, real world communities around the UK are using decentralised energy. As a result, they're enjoying lower greenhouse gas emissions, a more secure energy supply, cheaper electricity and heating bills and a whole new attitude towards energy.



See:
http://www.greenpeace.org.uk/files/efficiencity/index.html
http://www.greenpeace.org.uk/efficiencity/about

Tidal Lagoons

Swansea Bay in Wales is set to house the world's first tidal lagoon. Using the predictable movement of the tide the lagoon will produce clean, green and effortless energy. Peter Ullman, chairman of Tidal Electric, explains how energy circles in the sea could supply nearly a tenth of the UK's power needs. The United Kingdom has the second highest tidal range in the world.

How do tidal lagoons work?

The lagoon is an area of water cut off from the rest of the sea. When the tide drops you get a difference in water level inside and outside of the lagoon. The water is then released. It passes through turbines creating power. After the tide rises it generates more power during filling. So it works in both directions. Sounds like science-fiction... It's here now. Tidal lagoon technology doesn't have a huge learning curve to climb. And the turbines have been in use for over 130 years - there's about half a million of them in the world today.  

How clean are they?

There's no fuel of any sort involved. There are no temperature changes in the water and there's nothing emitted.

What's in it for local people?
It's likely to attract tourists - a major source of income. In addition it could protect coastlines where erosion is a serious problem. Tidal lagoons don't require any Government subsidy. Tidal lagoons could contribute significantly to the UK power mix and create a number of jobs.

Will marine life suffer?
No. The tidal lagoon doesn't block fish migration. It will create a habitat for fish and other marine life.

When will Swansea Bay be ready?
A realistic guess would be 3 years. The only thing holding it back is the process of getting permission. Local citizens, businesses and local politicians have all been very supportive

For more details see http://www.tidalelectric.com/