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

BedZED - Sustainable Homes

The Beddington Zero Energy Development, or BedZED for short, is the UK’s largest carbon neutral development. It provides 82 residential homes with a mixture of tenures and sizes. The project also includes buildings for commercial use, an exhibition centre, a children's nursery and a show flat so that visitors may see what it is like to live at BedZED.

Buildings are constructed from thermally massive materials that store heat during warm conditions and release heat at cooler times. In addition, all buildings are enclosed in a 300mm insulation jacket.
BedZED houses are arranged in south facing terraces to maximise heat gain from the sun, known as passive solar gain. Each terrace is backed by north facing offices, where minimal solar gain reduces the tendency to overheat and the need for energy hungry air conditioning.

Where possible, BedZED was built from natural, recycled or reclaimed materials. All the wood used has been approved by the Forest Stewardship Council or comparable organisations.
BedZED homes and offices are fitted with low energy lighting and energy efficient appliances to reduce electricity requirements. Visible meters are mounted in homes and offices so the occupiers can keep tabs on their electricity consumption.

BedZED receives power from a small-scale combined heat and power plant (CHP). In conventional energy generation, the heat that is produced as a by-product of generating electricity is lost. With CHP technology, this heat can be harnessed and put to use. At BedZED, the heat from the CHP provides hot water, which is distributed around the site via a district heating system of super-insulated pipes. The CHP plant is powered by off-cuts from tree surgery waste that would otherwise go to landfill. Should residents or workers require a heating boost, each home or office has a domestic hot water tank that doubles as a radiator.

Making the roof areas green with sedum plants helps increase the site’s ecological value and its carbon absorbing ability, as well as giving the occupants private gardens. Next to the green roofs are the photovoltaic panels to generate electricity.

Transport energy accounts for a large proportion of the energy consumption of any development. A green transport plan promotes walking, cycling and use of public transport. A car pool for residents has been established. BedZED has good public transport links, including two railway stations, two bus routes and a tramlink. On-site charging points for electric cars and a free public electric vehicle charging point is already available in Sutton town centre. BedZED's 10-year target is to produce enough electricity from photovoltaic panels (which convert sunlight into energy) to power 40 electric vehicles. It is hoped that a mixture of private cars and vehicles available through the car club will minimise fossil fuel use as the community settles. For owners of electric vehicles energy and parking will be free of charge.

To find out more search Google for “BedZed” or visit http://www.zedfactory.com/projects_mixeduse_bedzed.html

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

Decentralised Energy: Woking Council Case Study

Woking Borough Council has pioneered a network of over 60 local generators, including cogeneration and trigeneration plant, photovoltaic arrays and a hydrogen fuel cell station, to power, heat and cool municipal buildings and social housing. Many town centre businesses are also connected to this local energy supply. The Woking energy model produces dramatic savings in energy use and greenhouse gas emissions. With further help from energy efficiency measures, the council has reduced CO2 emissions associated with the operations of its own estate, including social housing, by a staggering 77% over just 15 years. Some sophisticated engineering solutions have been deployed, including large thermal stores in the town centre car park and at the leisure centre at Woking Park. The balancing of the system is performed entirely by computer, and the control system can be readily accessed by remote engineers or council officers.

The generators are connected to users via private electricity wires owned and operated by Thameswey Energy Ltd – a company set up and partly owned by Thameswey Ltd, a municipal energy and environmental services company itself wholly owned by Woking Borough Council. These private wires have points of connection to the local distribution networks (in turn connected to the national grid), but in 2003 the council’s electricity infrastructure was 99.85% self-sufficient. In the event of a grid power cut the system can switch to island generation mode, meaning businesses and householders connected to the private wires continue to be supplied with electricity with only a short interruption while the system disconnects from the dead grid and restarts using a small black start generator (a generator which can start up with no external power input).



Woking was able to raise capital for energy infrastructure development initially through energy efficiency savings. A fund mechanism was established in a benchmark year for energy expenditure, against which savings accruing from energy efficiency measures were recycled, year on year, into further energy-saving initiatives. The substantial financial savings allowed the council to invest millions in energy supply innovation. Moreover, Thameswey Energy Ltd has attracted investment from Danish pension companies who recognise the steady low-risk return the initiative offers – energy systems like Woking’s are a common component of investment portfolios for pension and insurance companies across Europe.

Developing a private network enabled Thameswey Energy Ltd to avoid charges usually associated with the use of the grid. By circumventing these costs, it has been able to fund wires and generation to deliver low emission electricity in competition with conventional suppliers. For domestic customers in social housing, Thameswey provides electricity below the rate of other electricity suppliers as part of Woking Borough Council’s fuel poverty programme. The council estimates that it supplies heat and power to potentially fuel-poor households for 6–7% of the state pension – well below the 10% threshold of all household income spent on heating that the Government uses to  define fuel poverty.

While the Woking model is widely celebrated in energy circles, its significance for UK energy policy has yet to be fully appreciated. It shows that renewable technologies and cogeneration are highly complementary and lend themselves flexibly to a piecemeal engineering approach as finances allow. The key lesson from Woking is that, liberated from the constraints of centralised rules and infrastructure, cogeneration and renewables can assert their own competitive potential.

See www.greenpeace.org.uk/DecentralisingPower_summary or www.woking.gov.uk for more details.