Transition in Action, Totnes 2030, an Energy Descent Action Plan

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The National Energy Picture: where our energy comes from at the moment

Although different kinds of fuels are used for producing different types of energy, it is important to note that not all are interchangeable.

Fossil fuels

Oil has a high energy density and its liquid nature makes it easily transportable. It is used for over 90% of the world’s transport and is an important raw material for the plastics, chemical and pharmaceutical industries. Oil is also used for making pesticides and other agrochemicals. The UK was self-reliant for oil, and for gas, profiting from exports of both, until 2003.
Gas requires more stringent measures to contain and transport and is more suited to static applications such as cooking, space heating and water heating and electricity generation. It is also used as a raw material for fertilizer production. Global peak gas is expected around 10 years later than oil, but when that peak comes it will be more abrupt than the oil peak. The UK is more dependent on natural gas than most other countries. 38% of UK primary energy comes from gas, as opposed to, for example, 25% in the US.
Coal is the least energy dense (but most carbon rich) of the fossil fuels. Its primary use in the UK is electricity generation; worldwide use is growing more rapidly than any other fuel. Global peak coal is expected around 2025 and the quality of the coal being mined around the world is falling sharply.
Other non-conventional oil resources include deep-water oil, polar oil, heavy oil, tar sands and oil shale. These require high investment in energy (giving a low EROEI¹) to recover them and their carbon implications are such that their use should be avoided.

Nuclear Power

Nuclear energy is produced as electricity from fission of uranium oxide, a finite resource. It currently accounts for about 3% of total UK energy supply. The EROEI of nuclear power is worsening as stocks of high quality uranium ore deplete although there are clearly differing ideas about how long reserves may last. The DARE report states that under current consumption levels the world’s known reserves may last 60 years². However in another scenario Professor David MacKay suggests thorium could yield 120 kWh/day per person for 60,000 years³. Dr Colin Campbell of ASPO has stated that “if the all the world converted to nuclear tomorrow, this would last about 3 years”⁴. Production of nuclear power also uses fossil fuels at most stages of its production.

Global warming is also having an impact on nuclear power production. Natural streams are used for cooling purposes; as global temperatures and sea temperatures rise these streams will reach the power plants at higher temperatures, thus less cooling is possible. Nuclear power plants in France have already had to operate below capacity due to this effect and their legislative upper limit of 24 C for receiving waters post discharge.

Nuclear fusion (based on light elements, e.g. hydrogen & lithium) has been researched for over 2 decades, but has not yet provided a reliable source of clean or cheap energy. Its potential contribution towards energy provision remains speculative. Lithium – a likely vanishing resource – is relatively uncommon in the earth’s crust (and China has been buying up lithium mining rights over the past decade); this could also have serious implications for electric cars and similar vehicles, as lithium is currently a key component of their batteries.

Energy from renewable supplies

In 2007 just 1.5%⁵ of the total UK energy supply came from renewable sources, and much of that was methane gas reclaimed from landfill sites. Renewable energy is an integral part of the Government’s longer-term aim of reducing CO₂ emissions by 80% by 2050, a figure now matched by the rest of the G8 countries. In 2000 the Government set a target of 10% of electricity supply from renewable energy by 2010, and in 2006 announced an aspiration to double that level by 2020⁶.

Footnotes

Energy Return on Energy Invested [↩]
DARE report. (2006) Devon Association for Renewable Energy www.devondare.org [↩]
Sustainable Energy – without the hot air p.166 [↩]
Dr Colin Campbell, Then Chairman of the Association for the Study of Peak Oil (ASPO). 2004 [↩]
Alastair Gill of RWE Innogy given at a presentation to the 2008 Renewable Futures conference in Bristol, primary energy from renewables was only 1.5% [↩]
BERR website: www.berr.gov.uk/energy/sources/renewables [↩]

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