2008年2月12日火曜日


The production of renewable energy in Scotland is an issue that has come to the fore in technical, economic, and political terms during the opening years of the 21st century.

Biofuels
Biomass
Geothermal power
Hydro power
Solar power
Tidal power
Wave power
Wind power Realisation of the potential

Main article: Wind power in Scotland Wind power
Further information: Wave power
Various systems are under development at present aimed at harnessing the enormous potential available for wave power off Scotland's coasts. Ocean Power Delivery are an Edinburgh-based company whose Pelamis system has been tested off Orkney and Portugal. These devices are 150 metres (492 ft) long, 3.5 metres (11.5 ft) diameter floating tubes which capture the mechanical action of the waves. Future wave farm projects could involve an arrangement of interlinked 750 kW machines connected to shore by a subsea transmission cable.

Wave power
Further information: Tidal power
Unlike wind and wave, tidal power is an inherently predictable source. However the technology is in its infancy and numerous devices are in the prototype stages. Today we know that a tall tubular tower with three blades attached to it is the typical profile of a wind turbine, but twenty-five years ago there were a wide variety of different systems being tested.

Tidal power
Further information: Hydro power
Scotland has 85% of the UK's hydro-electric energy resource,

Hydro-electric power
Further information: Biofuels

Biofuels
Various biodiesel schemes exist at present, and as with most renewables, interest is growing in the subject. Westray Development Trust operate a biodiesel vehicle fueled by the residual vegetable oils from the Orkney archipelago fish and chip outlets.

Anaerobic digestion and landfill gas
Further information: Biomass
Wood fuel almost certainly exceeds hydroelectric and wind as the largest source of renewable energy at present. Scotland's forests, which currently make up 60% of the UK resource base,

Solid biomass
The Energy Savings Trust estimate that micro-generation could provide 30–40% of the UK's electricity demand by 2050

Micro systems
Further information: Solar power
Despite Scotland's relatively low level of sunshine hours, solar panels can work effectively as they are capable of producing hot water even in cloudy weather. which in the Scottish context is the approximate equivalent of 0.07 GW or less of installed capacity.

Solar energy
Further information: Geothermal power
Geothermal energy is obtained by tapping the heat of the earth itself. Most systems in Scotland provide heating through a ground source heat pump which brings energy to the surface via shallow pipe works. An example is the Glenalmond Street project in Shettleston, which uses a combination of solar and geothermal energy to heat 16 houses. Water in a coal mine 100 metres (328 ft) below ground level is heated by geothermal energy and maintained at a temperature of about 12 °C (54 °F) throughout the year. The warmed water is raised and passed through a heat pump, boosting the temperature to 55 °C (131 °F), and is then distributed to the houses providing heating to radiators.

Geothermal energy
It is clear that if carbon emissions are to be reduced, a combination of increased production from renewables and decreased consumption of energy in general and fossil fuels in particular will be required. A variety of other options exist, most of which may affect development of renewable technologies even if they are not means of producing energy from renewable sources themselves.

Other means of reducing carbon emissions
Various other ideas for renewable energy in the early stages of development, such as ocean thermal energy conversion, deep lake water cooling, and blue energy, have received little attention in Scotland, presumably because the potential is so significant for less speculative technologies.

Other renewable options
Carbon offsetting involves individuals or organisations compensating for their use of fossil fuels by making payments to projects that aim to neutralise the effect of these carbon emissions. Although the idea has become fashionable, the theory has received serious criticism of late. The weaknesses of the approach include uncertainty as to whether the planting might have occurred anyway and who, in the future, will ensure permanence. However, there is likely to be a greater level of credibility inherent in a nearby and visible scheme than in a far-distant one.

Carbon offsetting
The following technologies are means of reducing the effect of carbon emissions and form an important aspect of the energy debate in Scotland and are included here for completeness. Their effect is likely to influence the future direction of commercial renewable energy, but they are not renewable forms of energy production themselves.
Carbon sequestration: Also known as carbon capture and storage, this technology involves the storage of carbon dioxide (CO2) that is a by-product of industrial processes through its injection into oil fields. It is not a form of renewable energy production, but it may be a way to significantly reduce the effect of fossil fuels whilst renewables are commercialised. It may also be an intermediate step towards a 'hydrogen economy' (see below), which could either enable further renewable development or conceivably out-compete it. The technology has been successfully pioneered in Norway

Challenges and opportunities offered by non-renewables
Although hydrogen offers significant potential as an alternative to hydrocarbons as a carrier of energy, neither hydrogen itself nor the associated fuel cell technologies are sources of energy in themselves. Nevertheless, the combination of renewable technologies and hydrogen is of considerable interest to those seeking alternatives to fossil fuels.

Hydrogen
A significant feature of Scotland's renewable potential is that the resources are largely distant from the main centres of population. This is by no means coincidental. The power of wind, wave and tide on the north and west coasts and for hydro in the mountains makes for dramatic scenery, but sometimes harsh living conditions. W. H. Murray described the Hebrides as "the Isles on the Edge of the Sea where men are welcome—if they are hard in body and in spirit tenacious."

Local vs national concerns
Growing national concerns regarding 'Peak Oil' and climate change have driven the subject of renewable energy high up the political agenda. Various public bodies and public-private partnerships have been created to develop the potential. The Scottish Renewables Forum is an important intermediary organisation for the industry, hosting the annual Green Energy Awards. The Highlands and Islands Community Energy Company (HICEC) provides advice, grant funding and finance for renewable energy projects developed by community groups in the north and west of Scotland. Areg is a public-private partnership created to identify and promote renewable energy opportunities for businesses in the north-east.

Renewable energy in Scotland Promotion of renewables
New data appears on a regular basis and milestones in 2007 include the following.
In February the commissioning of the Braes of Doune wind farm took the UK renewables installed capacity up to 2GW.

Recent events
Table notes
a. The above figures assume 12% by 2020.
Blank entries mean no data is available. In the cases of the current capacity of biomass, biodiesel and geothermal these will have been very small.

See also

Monbiot, George (2006) Heat: How to Stop the Planet Burning. London. Allen Lane.
RSPB Scotland, WWF Scotland and FOE Scotland (February 2006) The Power of Scotland: Cutting Carbon with Scotland's Renewable Energy. RSPB et al.
Scottish Executive (2005) Choosing Our Future: Scotland's Sustainable Development Strategy. Edinburgh.
Scottish Renewables Forum. Market and Planning Reports (various).
The Role of Nuclear Power in a Low Carbon Economy. (2006) Sustainable Development Commission. London.
Royal Society of Edinburgh (June 2006) Inquiry into Energy Issues for Scotland. Final Report. Edinburgh. RSE.

1 件のコメント:

sdenterprise さんのコメント...

The key to all of this is the mix, local renewable energy sources where the technology is community owned or coop owned is one of the best models to move forward...

If the local community benefit from locally farmed energy sources providing a large percentage of their energy needs within the community, then there would be little or no need for mass production and transporttion accross sections of countryside.

There are many opportunities in Scotland and the rest of the UK for renewable energy sources, we just have to take a chance and make the changes...