NOT ENOUGH SAFE ENERGY: EARTH

1. ENERGY: RESOURCE DEPLETION AND ENVIRONMENTAL IMPACTS

The relationships between energy needs and sustainable population levels are complex. There are two main aspects to the question of energy: first, as a resource, and second as an environmental impact (pollution). In the past, the debate has centred on resource depletion and pollution and in the 1990s the pollution arguments were joined by fears about a particularly insidious form of pollution - greenhouse gas emissions - that would cause climate change.

So in considering a sustainable population size for Earth, in relation to energy, it is necessary to look at (1) the consumption and depletion of energy resources over a period (by a given population at a given standard of living and level of technology); and (2) at the environmental impact of this consumption, currently most importantly in terms of greenhouse gas emissions. In both cases, scenarios based on fossil-fuel and/or nuclear and/or renewable resources need to be examined. Renewables are cleaner in terms of emissions impacts, but are currently less effective than fossil fuels and can therefore sustain fewer numbers. Liquid fuels needed for motorised transport also need to be compared in terms of energy content. The energy content (measured in Megajoules per litre) of ethanol produced from biomass, for example, is about two-thirds that of petrol (gasoline). See OPT Research: Wind and biomass.

2. SUMMARY: EARTH

World population growth has already had a significant effect on energy demand, and continues to undermine efforts to substitute green energy supplies for fossil fuels. While world renewable energy supply grew by an average 2.3% a year from 1971 to 2004 [IEA Factsheet, 21 Feb 2006], world population growth continued to increase the number of energy consumers, by 1.6% a year. Rising per capita consumption by rising numbers of consumers has propelled demand for all forms of primary energy, including fossil fuels, and has been exacerbated by rapid globalisation and urbanisation as populations have migrated from less developed regions to more developed regions with high-energy consumption lifestyles.

When the World Energy Council produced its Survey of Energy Resources 2004, it concluded that "There is no shortage of global energy resources". Estimates were that the world had 40 years of oil supply available, 60 years of natural gas, and 200 years of coal. [2004 Survey presentation by Dr Alessandro Clerici, Chairman, Survey of Energy Sources Committee, WEC]. Of the main greenhouse-gas producing fossil fuels (oil, gas and coal) coal remains available in quantity but poses severe emissions problems. But there are conflicting estimates for production of the other two, oil and gas, with many industry experts predicting that it could peak before 2020, with discoveries less frequent, reserves being depleted rapidly, and world energy demand growing along with population growth. Of substitute fuels, nuclear power has produced high levels of radioactive waste and clean-up costs are rendering it uncompetitive with other sources.

Some renewable forms of energy are entering the mainstream - for example, wind - but at current technology are less effective in energy conversion terms than fossil fuels and/or occupy large areas of land or sea. There are still considerable technical and economic problems (after decades of research and development) with solar photovoltaics and hydrogen fuel cells; yields from solar energy may improve with the development of mass-mirror solar power stations, but the yields from biomass required for renewable liquid fuels such as methanol are low in terms of land use and net energy capture.

While world population is expected to grow by 2.6 billion to 9.1 billion by 2050 - currently increasing the number of energy consumers by some 75 million a year - there is no convincing evidence that clean, safe and affordable energy can be supplied in time to meet expected demand. World growth in renewable energy supply is forecast to grow from over 1,400 Mtoe in 2003 to almost 2,300 Mtoe in 2030, a rise of only 1.8% a year.

Meanwhile, the impact of fossil fuel use on the environment is worsening. In October 2004 the International Energy Agency (IEA) [World Energy Outlook 2004] concluded that "the world is not running out of oil just yet", but that carbon dioxide emissions are expected to be nearly 40% higher in 2010 than they were in 1990 - instead of 60% lower, as recommended by the Intergovernmental Panel on Climate Change and the Royal Commission on Environmental Pollution (see Climate change), or the 80-90% cut now called for by some climate change scientists. The IEA presented alternative energy scenarios showing how energy demand - predicted to rise 60% between 2004 and 2030 - could be cut. Economic growth has become less energy intensive in percentage terms, but actual consumption is rising and the number of consumers also continues to rise.

The debate about global energy has rightly focused on a need to reduce excessive consumption by developed countries while recognising that developing countries will consume more. The weakness of this position, however, is that if the number of consumers continues to increase even a modest universal quality of life, based on equitable and sustainable consumption, may never be reached. Had calls for global population stabilisation been heeded in the mid-20th century, when world population stood at 2.5 billion, rising demand for energy might not be creating a crisis now.

3. WORLD COAL, OIL AND GAS

Will coal take the title of 'black gold' from oil as oil runs out? Of the three main fossil fuels, only coal remains in abundant supply, with the USA owning the largest share of world reserves (27%), Russia next (17.3%) and China third with 12.6%. Unfortunately coal is the most damaging energy source in terms of emissions, and the prospect of 'green' coal, scrubbed and cleaned, with its carbon captured and stored underground, remains distant. World coal consumption in 1980 was 4,127 million short tons (mst), producing 1,763 million metric tons of carbon equivalent (mmtce), according to the US Energy Information Administration. By 2003 the world was consuming 5,439 mst a year and emitting 2,537 mmtce, as both Russia and China enjoyed headlong economic growth. China, with 1.3 billion people, consumed much more coal than Russia, with 144 million. Yet the West continues to mock China for its population policy - a policy too draconian for other countries to emulate, but one that has spared the world an additional 400 million energy consumers and polluters.

The effects of a collision between rapidly rising demand for fossil fuels and peaking supply have defied all predictions - except those of environmentalists. As the latent demand of a vastly expanded world population has been fuelled by rapid economic development, consumption has soared. World oil consumption multiplied sixfold between 1950 and 2000, when it averaged 75.8 million barrels a day (mbd) [BP Statistical Review of World Energy, June 2005]. In 2005 it reached an estimated 83.3 mbd, with China, home to a fifth of the world's consumers, accounting for most of the extra demand. [IEA]. World demand is forecast to grow 50% by 2025, to 120 million barrels a day [International Energy Outlook 2004, US Department of Energy, Feb 2004], partly due to the addition of another 1.3 billion more people to the planet - another China by 2025 [UN World Population Prospects, 2004 Revision, Medium Variant Projection].

But annual oil production, at 80.3 mbd in 2004 (only 20% higher than in 1994) is levelling off as new sources become more difficult to find, less secure, and more expensive to bring to the market. In 2002 the price of oil began its relentless climb from $20 a barrel. Most analysts continued to believe that this rise would soon be reversed (OPT, taking into account demographic as well as economic factors, did not hold this view). By mid-July 2006, with crude oil breaching $75 a barrel, political instability in oil-producing regions and the costs of extraction climbing, even energy industry leaders began to acknowledge that projected demand over the next 20 years is unlikely to be met. If policies could be introduced to lower world population growth to the UN's 'Low Growth' variant projection, there would be many million fewer energy consumers at that point than indicated by the 'Medium Growth' projection.

Estimates of the date at which world oil production will peak and begin to decline vary. Oil production is already in decline in 33 of the world's 48 largest oil-producing countries [see The Inevitable Peaking of World Oil Production , The Atlantic Council, Robert Hirsch, Oct 2005]. Production of all liquids, including Orinoco extra-heavy oils, Athabasca tar sands, synthetic oils, Natural Gas Liquids and refinery gains forecast by Jean Laharrere for ASPO (the Association for the Study of Peak Oil), is expected to peak around 2015 at 90 Mb/day, on the basis of about 3000Gb ultimate production, and ASPO's 2004-based peak oil and gas projection is shown in Chart 3.1 below. See ASPO, Oil Depletion Analysis Centre, and British Petroleum.

Even the oil industry acknowledges that future oil reserves will be difficult to extract and therefore production costs and oil prices will be higher. Does the industry profit from high oil prices? Yes - but diversification into non-oil energy underlines reveals the underlying realities. Setting aside the question of climate impact, it is clear that the world as a whole and particularly Europe (with only 18.7 billion barrels of proven resources), will be heavily dependent on non-fossil fuel energy sources before 2050. Is that the solution to atmospheric pollution? No - because emissions pumped from pre-2050 consumption will blanket the atmosphere for up to 100 years, and because the irreversible 'tipping point' of rising temperatures may be as little as 10-20 years from now. (See Climate.)

Natural gas is a slightly cleaner source of energy than oil, and with rising oil prices world gas consumption, reached 2.69 trillion cubic metres in 2004, up 29% from 1994, [SRWE 2005, BP]. While gas production is projected to peak a decade or more later than oil, Laharrere of ASPO forecasts that peak production of all hydrocarbons (about 3 Tboe of oil liquids plus 2 Tboe of gas) will occur in about 2025, at about 55Gboe per annum - 20% higher than at present - if there is no constraint on demand.

Oil consumption will need to be constrained for climate change reasons alone. However, even if demand is suppressed, the world has a 'window' of only 20-30 years in which to make very large-scale substitution of fossil fuel by green forms of energy. It is generally agreed that oil and gas will become scarce by 2050 and revert to around 1950 levels by 2100. Forecast peaks in oil and gas supply can be deferred by constraining demand by a variety of methods - conservation, taxation, and innovation and competitive production of other forms of energy. However, world population in 2100, if it continues to grow as projected, will be at least three times larger than it was in 1950 (then 2.5 billion). Oil and gas supplies would therefore, even if maintained, be one-third per capita of the level they were in 1950. Population stabilisation and decrease can play a vital part in helping to solve the world's energy problems.

4. WORLD NUCLEAR POWER

There were 441 commercial nuclear power stations operating in 31 countries worldwide in 2006, with a total capacity of 364,000 MWe, producing more than 16% of the world's electricity. Different types of reactor include the Pressurised Water Reactor (PWR), Boiling Water Reactor (BWR), Gas-cooled Reactor (Magnox & AGR), Pressurised Heavy Water Reactor (PHWR), Light Water Graphite Reactor (RBMK) and Fast Neutron Reactor (FBR). See World Nuclear Association.. Some 30 new reactors are under construction in 11 countries, and at least 60 new plants are forecast to be completed in the next 14 years, which would put 430,000 MWe in place in 2020, according to the International Atomic Energy Agency..

Nuclear power produces lower greenhouse gas emissions than fossil fuel power, and enables countries to maintain security of supply, but is considered a high-risk source of energy for other security reasons, and because of the dangers of accumulating radioactive wastes. During 10,000 cumulative reactor-years of operation in 32 countries, there have been two major accidents - at Three Mile Island, where the accident was contained (USA, 1979); and at Chernobyl (Ukraine, 1986) where an uncontrolled release of radioactive material had serious consequences. These dangers have recently been added to by the threat of terrorist attacks on nuclear installations. Longer-term challenges include the high cost of building nuclear power stations, the threat of rising sea levels to coastal installations, and the long-term availability of uranium of enrichable quality. Worldwide moves to install nuclear power to combat climate change have also raised the price of uranium, with the spot price of uranium oxide rising from $10 per pound in June 2002 to $85 per pound in February 2007 as demand outpaced supply. And although uranium is abundant, at the point at which it takes more energy to extract uranium than can be generated by its use by a nuclear reactor, nuclear fission becomes unviable. And although new nuclear reactors are less land-intensive than older installations, there will be political and environmental difficulties in choosing new nuclear sites in densely populated countries such as the UK (see section 10 below).

5. WORLD RENEWABLE ENERGY

Renewables are seen mainly as substitute sources for power (electricity) rather than as substitutes for petroleum (oil), although biomass products such as ethanol are already being used as fuel additives and can play a larger part as transport fuels. Solar, wind, wave, tidal, biomass and hydrogen are among the renewable power sources cited as solutions to providing clean energy for a growing world population. Worldwide, their contribution is growing fast (see Chart 2.1 above). Already renewables are the third largest contributor to global electricity production, accounting for 18% in 2003, with the bulk coming from hydro-electric power plants. Total renewable energy supply is forecast to increase by more than 60% from 2003 to 2030, according to the International Energy Agency [Renewables in global energy supply, 21 Feb 2006].

Theoretically, the prospects for renewable energy are almost unlimited. Wind-generated waves on the ocean surface of the world, for example, have a total estimated power of 90 million GW, and worldwide about 3,000GW of energy is estimated to be continuously available from the actions of tides, though only 60GW is likely to be recoverable for electricity generation. But renewable energy is not growing fast enough to reduce fossil fuel demand. Some renewable technologies have been promised for 20-50 years, but have yet to deliver results at viable prices. Most, including wind power, pose considerable problems in development, such as low net energy yields, large sea or land area requirements, high capital costs and lack of reliability. While renewable energy and fuels must be developed, estimates of their benefits and costs must be realistic, both in financial terms and in terms of net energy yields. For OPT research on energy, see the OPT Journal.

NOT ENOUGH SAFE ENERGY: EUROPE

6. ENERGY BACKGROUND EUROPE

The European Union - now the EU 25 - recognised its precarious energy situation in its European Commission Green Paper: A European Strategy for Sustainable, Competitive and Secure Energy on European Energy Policy published in March 2006. According to the EU, world energy demand and carbon dioxide emissions are expected to rise by some 60% by 2030 - and it concluded that Europe must act urgently. "Our import dependency is rising. Unless we can make domestic energy more competitive, in the next 20-30 years around 70% of the Union's energy requirements, compared to 50% today, will be met by imported products - some from regions threatened by insecurity." And although the EU is ahead of other world regions in slowing greenhouse gas emissions, it has a big green gap to close. By 2030, CO2 emissions, far from meeting the minimum 60% cut now called for by the scientific community, may be 14% higher than their 1990 level [Baseline Scenario, European Energy and Transport Scenarios on Key Drivers, Sep 2004] if no further efforts are made.

Europe plans to cut internal energy costs by completing the internal market for gas and electricity, including developing a European grid for electricity and gas, but that will not increase supplies from outside the EU. It plans to introduce buffer stocks of gas (reserve supplies) to add to those of oil, to safeguard against disruption of supplies, but that will not increase supplies from outside the EU. Some of these measures are already being contested by different national interests within the EU. There are, however, plans to make the EU more self-sufficient in energy, with an ambitious EC Green Paper on Energy Efficiency [June 2005] aimed at saving a fifth of EU energy by 2020; by cooperative energy technology research, and by working on a new 'road map' for renewable energy, with targets for 2020 and beyond.

So how is the EU placed in terms of energy supply? With primary energy demand expected to grow by a fifth by 2030 under its baseline scenario, the EU25 will rely on imports for 67% of its energy. Oil would meet 34% of primary energy demand; gas 32%; nuclear 9.4%; with renewables increasing only modestly to 8.6%; and coal, solid and waste fuels making up the remaining supply. (See Baseline Scenario, European Energy and Transport Scenarios on Key Drivers, September 2004) . The EU is already failing to meet green energy targets - for example a 2001 agreement that the share of electricity consumption from renewable energy sources should reach 21% by 2010 will be "missed by 1-2 percentage points". The outlook for liquid fuels is no better: EU biofuels production, for example, is predicted by the EurObserver Biofuels Barometer 2006 to reach only half the target (its 5.75% share of transport fuels by energy) required by a recent EU Biofuels Directive.

And how is the EU placed, in terms of population numbers? Here the outlook is rosier. EU25 2004-based population projections show numbers continuing to grow from 459 million in 2005 to peak at 470 million in 2025, then gradually decreasing to 450 million in 2050. (See Europe: Chart 1.1). By 2030, EU population will be back to today's level, which means that household fragmentation - the increase in households caused by people choosing to live alone, divorcing more often and living longer - will no longer be augmented by direct population growth (natural increase + net migration). Even without projected population growth from 2005-2030, however, the EU might have to build 32 million more homes (households) - more than four Londons. With additional people, household growth would be higher. How would further population growth, adding perhaps six Londons by 2030, ease the EU's energy gap?

As in the UK, this question remains unanswered. OPT maintains that providing the EU population does not age too sharply, the problems associated with rising numbers of older people in relation to the workforce can be alleviated with moderate, fixed-term inflows of migrant labour, and a gradually decreasing population can only be welcomed. The European Commission's energy plans are radical, and greener than those of most of the developed world. But they carry no explicit recognition that a stable or gradually decreasing population is an energy benefit, and therefore should be a positive policy driver. In simple environmental terms: without radical change, more people will mean more energy consumers and more greenhouse gas emitters. In simple economic terms: if additional people do not contribute to export earnings to pay for foreign energy supplies, population pressure on energy demand is also likely to worsen the UK balance of payments.

Though the relationships between population numbers and energy use are complex and diffuse, there are signs, however, that for other reasons the EU no longer believes in unlimited population growth - see Europe .

NOT ENOUGH SAFE ENERGY: UK

7. THE WIDENING UK ENERGY GAP

Politicians, economists, scientists, environmentalists and businesses all now agree that the UK does not have enough clean, secure energy to meet future needs. Most recognise that fossil fuel consumption cannot continue at its present rate. For governments and consumers a key issue is affordability; from an environmentalist's point of view a key issue is to determine which forms of energy are environmentally safest, so that greenhouse gas emissions can be rapidly reduced. But neither side has considered the part that population policy can play - at its simplest by reducing the rising demand caused by growing numbers of energy users - UK population growth is now running at more than 300,000 a year.

The ecological and resource-use issues that should underpin decisions about the UK's long-term energy supply are regularly examined in the OPT Journal. Considered here are the current UK energy gap and the contribution that could be made by stabilising and gradually decreasing UK population. For up-to-date information on UK energy see Digest of UK Energy Statistics (DUKES) 2005 [Department for Trade and Industry], published July 2005.

7.1 GOVERNMENT ACTION TOO LITTLE, TOO LATE

In its Energy White Paper Our Energy Future: creating a low-carbon economy, published on 24 February 2003, the UK government made a necessary and welcome commitment to renewable energy, pledging to maintain reliable energy supplies while cutting carbon emissions by 60% by 2050.

But creating a secure supply of low-carbon energy is not proving an easy task. More than 90% of UK primary energy consumed comes from finite fuels and by 2020 up to 80% of supply will have to come from foreign sources. In spite of soaring fossil fuel prices, solar power and biomass electricity generation have so far failed to provide cost-effective solutions, onshore wind farms have become increasingly unpopular, offshore wind remains expensive, and tidal and wave power are still largely in the development stage in the UK, and energy efficiency measures have had little effect - both consumption and emissions are still rising.

How far implementation of Our Energy Future has progressed became clear in the Second annual report on implementation of the Energy White Paper, published in July 2005. This indicated just how difficult it will be to provide clean energy, either for climate change reasons or to supply power in a post-fossil fuel age - for a population now rising by more than 300,000 a year. Had a population stabilisation policy been put into effect when the independent Population Panel reported in 1973, there might now be four million fewer energy consumers in the UK.

On 1 July 2003 a report published by the Institution of Civil Engineers [The State of the Nation 2003] had highlighted "a potential 80% shortfall in meeting the country's energy demands from current supplies by 2020", and pointed to the "possibly cataclysmic effects of becoming reliant upon unsecured, imported fuel supplies." The 2003 Energy White Paper 'aspiration' (already downgraded from a 'target') was for 20% of UK electricity to be met from renewable sources (wind, tidal, wave, solar and biomass) by 2020. This downgrading, with a specific target of only 10% of electricity to be provided by 2010 (39 terawatt hours a year of a total 371-390 TWh/y in 2010) indicated how short of indigenous power the UK is likely to be by 2020.

By the beginning of 2005, less than 3% of UK electricity was being met from indigenous renewable sources (see DTI Renewables information ). And with electricity accounting for less than 20% of final energy supply, the contribution from renewables appeared even smaller: just 0.6%. Four-fifths of the UK's final energy consumption is of oil and natural gas (Chart 7.2.3), mainly for transport and heating buildings. An even greater challenge than finding new ways of generating electricity will be creating low-carbon substitutes for the petroleum which accounts for nearly half our primary energy consumption (see chart 7.2.1).

While renewables come onstream at a crawling pace, rising global demand for finite fuels has pushed prices up sharply. In 2001, according to Energywatch, UK household energy bills were at their lowest level since 1974. The downward trend, partly due to privatisation and new competition within the energy industry, then went into a steep reversal: since 2003 average domestic gas bills have climbed 75%, with electricity bills up 45%. In the face of slow progress with renewables, rising energy costs and concerns about energy supply and security, the 2003 Energy White Paper was put under review. Consultations closed in April 2006 and the Review is due to be published in July 2006. Indications are that it will recommend building new nuclear capacity - bringing forward a decision that had previously been deferred until 2008.

7.2 ENERGY BACKGROUND: UK

UK energy production and consumption patterns have changed radically over the last 35 years. Domestic oil and gas production is no longer meeting UK needs, as it did in the last two decades of the 20th century - when spare capacity brought in valuable export earnings. In 2004, according to the Department for Trade and Industry (DUKES 2005), "overall primary fuel consumption was not met by indigenous production, and the UK became a net importer of fuel." The decline in self-sufficiency is steep, with UK production falling 8.5% in 2004 alone.

Charts 7.2.1 and 7.2.2 below identify the primary fuels that kept people in the UK switched on and mobile in 1970 and 2004 - a period of rapid shift to natural gas from coal, with continued high oil consumption. These show the types of fuel used in the UK as primary sources of energy (for example, natural gas that might be used either by a power station to produce electricity, or be supplied direct to a kitchen hob). In 2005, total primary fuel consumption for energy use was higher than in 1970, and the UK still depends on oil for a third of its primary energy needs. These charts exclude fuels consumed for non-energy use, such as oil used for making plastics. Most calculations in this briefing use as their basis the *161 Mtoe of total energy supplied to final users (see footnote).

The key to understanding the size of the UK energy gap, and the need for a smaller UK population alongside low-carbon, low-waste energy policies, is recognition of the insignificant contribution that low-carbon energy sources make to current energy supply, and the problems that beset substitution. Chart 7.2.3 below shows that we consume nearly half of our energy in the form of oil (petroleum), which cannot easily be provided on a large scale by renewables. Electricity, which can be provided by renewables or other low-carbon sources such as nuclear power, accounts for less than a fifth of our energy supply. So electricity supplied by nuclear power or renewables provides only a fraction of that 17.5% - see sections on Nuclear Power and Wind below.

By the time energy has been converted from primary fuels into secondary sources such as electricity, amounts have been lost in conversion and transmission. By the time energy had been supplied to its final user throughout 2005, whether a homeowner, driver, public sector user, business office or factory, it had been reduced to a total *159.5 mtoe (see Chart 7.3.1). And when electricity providers, whether nuclear, wind or other low-carbon generators, make claims about the number of homes they can power, for example, the public often believes the claimed contribution to total energy needs is bigger than it is. Electricity accounted for less than 20% of final fuel consumption (see Chart 7.2.3) - we depend on non-electricity sources such as petrol and heating oil for some 80% of overall energy supply. The UK is already struggling to meet its energy needs - why widen the gap further by allowing continuous population growth?

7.3 CAN ENERGY DECENTRALISATION AND EFFICIENCY CLOSE THE GAP?

Faith in 'decoupling' energy use from economic growth has proved optimistic. Energy efficiency helped the energy ratio (temperature-corrected energy consumption relative to GDP) to halve from 1970 to 2005, but this improvement has been mainly due to a shift in the economy from energy-intensive manufacturing industry to services. Meanwhile, with nearly 5 million more inhabitants added to the UK since 1970, more lone households, more household electrical appliances, more cheap airfares and more car use, it comes as no surprise that energy consumption has risen. Greater energy efficiency, decentralisation of supply (with developments in combined heat and power generation), and energy conservation, can help to close the gap. These and other advances would be consistently undermined by projected population growth of more than 10 million in the next six decades. But if UK population were to be allowed to decrease by 5 million instead (given stable per capita energy consumption), considerable energy savings could be made.

Chart 7.3.1 above shows the amount of energy supplied to final users in the UK in 2005. Domestic users now account for nearly a third of energy use, showing the impact of population size and household numbers on total demand. But that energy comes in different forms - see Chart 7.3.4 (to 2004) below:

8. OIL AND GAS: UK

Late 20th century population and economic growth in the UK was made easy by North Sea oil, but in In 2004 the UK became a net importer of both oil and natural gas. Oil and gas from the North Sea Continental Shelf has done little good to the environment but helped to support the UK economy from the 1970s, providing substantial foreign currency revenues and mitigating the declining exports of a shrinking manufacturing sector. In 2000 North Sea oil and gas still produced a healthy trade surplus of £3 billion, but future net imports of oil will widen the UK's already large current account balance of payments deficit. More than 30 billion barrels have been extracted from the North Sea since 1967, and remaining fields are becoming more difficult to exploit. The UK will also become increasingly dependent on potentially unstable sources, with a large proportion being imported from Russia.

As already stated, one crucial factor determining the size of population that can be sustained at a reasonable quality of life and that guarantees a functioning economy after 2020, is the ability to substitute renewables for oil and gas. Where oil and gas can be replaced by renewables-produced electricity or nuclear power, shortages will not be at their most severe: the severe difficulties will arise from shortages (at affordable prices) of liquid fuels - mainly petrol - see section 10.2 below.

9. ELECTRICITY

Power for industrial, commercial and domestic use is provided by electricity - but fossil fuels are still the main source of energy used to generate electricity. Nearly 20% of of electricity is generated by nuclear reactors, including imports of nuclear electricity from France, with most of the rest coming from gas-, oil- and coal-fired electricity generators. Only one nuclear power station in the UK may still be operational beyond 2020, however, and emissions constraints mean that coal-powered generating plants will close shortly after 2016. Meanwhile, renewable energy sources provide only a tiny fraction of the total requirement - the 3.6% (2004) of electricity supply coming from renewable sources - hydro, wind, solar, tidal, wave and biomass - has far to climb to make a difference.

If the government's 10% of electricity from renewables by 2010 target is met, along with a further 'aspiration' to supply 20% of electricity from renewables by 2020, it will certainly help to meet carbon emissions reductions as well as providing electricity. The 20% by 2020 aspiration, however, is unlikely to be achieved. Even if it is reached, the target represents only 20% of less than 20% of total energy demand. Renewables, including hydro-electricity which provides the largest share, will not be enough to secure enough safe energy supplies for more than a small proportion of an ever-growing UK population. So what are the nuclear options?

10 NUCLEAR POWER UK

10.1 NUCLEAR FISSION

Nuclear power provides just under 20% of UK electricity, with 23 operating commercial nuclear power reactors at 12 nuclear power stations, on 9 sites. The reactors are of three different types: 14 AGRs (advanced gas-cooled reactors) 8 Magnox (older gas-cooled Reactors), with one PWR (pressurised water reactor). (See Nuclear Industries Association, UK).

Nuclear power is low-carbon power. According to the NIA "Nuclear's current contribution of 20% of UK electricity avoids the emission of around 50Mt carbon dioxide a year (assuming its replacement by a coal/gas mix), or around 8% of the UK's total annual emissions" [Submission to Energy Review, 2006]. Whatever the environmental arguments for or against nuclear power (it provides low-carbon energy but produces dangerous radioactive waste), the fact is that with all except three power stations due for closure by 2020, its contribution to UK electricity supply is shrinking fast - even if closure of some reactors can be postponed. Building new capacity will be very expensive, with a 1.2 GW reactor costing about £2 billion to build [Sunday Times, 21 May 06].

Lead times for planning, financing and building new nuclear reactors are 10-15 years, and although smaller nuclear reactors are being developed which may reduce both lead times and land requirements, it is unlikely that government backing for new nuclear power in its Energy Review in 2006 would result in new nuclear energy becoming available before 2015.

While UK nuclear generating capacity is shrinking, estimates for cleaning up the debris of retiring nuclear power stations is estimated at £70-£90 billion, and radioactive waste is still mounting. According to the Committee on Radioactive Waste Management, nearly 90% of radioactive wastes comes from nuclear power stations. The volumes of radioactive wastes from existing power stations is likely to reach 473,000 cubic metres by 2100, with about 80,000 cubic metres of solid wastes already waiting for decisions about where to store them. The wastes differ in the strength of their radioactivity and the length of time they remain radioactive - which ranges from a few years to 250,000 years. About 2,000 cubic metres of High-Level Wastes (HLWs) account for 95% of total radioactivity, which would fill only the equivalent of 12.5 London double-decker buses - but the intermediate level wastes (ILWs) pose a bigger problem. It can take up to 100 years before a nuclear site can be freed for alternative use.

Land use requirements in the UK are also made more problematic by extreme population density - the UK is more densely populated than China, and England is the fourth most crowded country in the world - see Too Many UK . Though modern nuclear stations are more streamlined than their retiring counterparts, uninhabited coastal land is so scarce that building on new sites will be politically unacceptable. Supporters of nuclear power point to France as an example of the contribution it can make to a country's total energy needs. But France has more than twice the land area for a similar population size - therefore France has an unpopulated land area at least the size of Britain in which people can live if they do not want to be near a coastal power station. Add to UK overpopulation and land scarcity fears about security from terrorist action; the rising costs of enrichable uranium; the prospect of rising sea levels (water is needed to cool nuclear power reactors) and more frequent storm surges as climate changes - and the scope for substituting nuclear power for fossil-fuel electricity generation looks limited.

Because progress with renewable energy sources has been slow and the land (or sea) area requirements of wind power (the only mature clean energy industry) are large in relation to net energy yields, renewables will prove no substitute for current UK fossil fuel energy requirements. It may therefore be necessary to build some new nuclear capacity, and in its submission to the Energy Review 2006, the Nuclear Industries Association called for the building of 10GW of new nuclear reactors, to be built at five existing sites over a period of 15-20 years. The government appeared to have accepted the need for new nuclear capacity before the publication in July 2006 of its Energy Review.

10.2 NUCLEAR FUSION

This form of nuclear power would theoretically provide almost unlimited safe and clean energy without producing harmful emissions or radioactive waste. It has been talked about since the mid-20th century, some reaction processes have been achieved and government funding has been directed at overcoming considerable remaining problems such as the development of materials in which to contain the fusion process. UK nuclear fusion experts estimate that the first prototype nuclear fusion power plant might be built by 2035. This form of energy cannot be counted as a realistic option until such a prototype has been built and proved to operate effectively and safely, as well as provide power at reasonable cost.

11. RENEWABLE ENERGY: UK

The UK government's Energy White Paper of February 2003 stated an 'aspiration' that 20% of all power (electricity) should be produced from renewable sources by 2020. The Renewable Obligations target is that 10.4% of total electricity supplies of 324.3 TWh in 2010/11 should be provided by renewables - 33.7 TWh. By 2004, renewables were generating 3.86% of electricity. This does not take into account rising electricity demand caused by factors which include population growth. The government has pledged £1 billion of support for the industry by 2010. By 2004 the share of electrical power produced by renewables stood at 3.86%, using hydro, wind, solar, wave and bioenergy sources (biofuel sources include landfill gas, sewage sludge and municipal solid waste conversion). See breakdown above. Government aims to meet 10% of electricity supply from renewables by 2010 and 20% by 2020 look unachievable.

With large amounts of investment capital now pouring into renewables projects, the prospects for growth are promising, but progress is slow, expensive and limited by land scarcity - covering thousands of square miles with wind turbines in a crowded country wins no popularity in politics. Curbing population growth, however, which would reduce demand, is a measure supported by the majority of people in the UK.

It is clear that renewable energy sources cannot provide continuous energy for more than 60 million people by 2020, and - in the absence of radical new renewables technology - unlikely by 2050. Wind, wave and solar sources are intermittent and there are no means to store enough of their output for use when the wind does not blow or the sun does not shine. Since Britain produces only about 15% of the wood it needs, production of extra wood or biomass to burn for electricity production would require huge areas of land to be taken out of food production. See also the OPT Journal Wind and biomass .

While recent North Sea oil finds mean that UK oil reserves may not decline as fast as previously expected, it will eventually become unaffordable (or its use curbed because of climate change dangers), and will inevitably run out. Prospects for producing enough liquid biofuels for use in motorised agriculture and transport (after using oil ceases to be affordable or has to be constrained for climate change reasons), are not good. Liquid fuel can be produced from wood, oil seed crops and other biomass, but much of the output would be used in its production, and again, much land would have to be taken out of food production. See 11.3 below.

There are several methods of generating 'renewable' energy - mainly by hydroelectric power, solar power, wind power, wave power, tidal power and biofuels (methods that require large energy inputs from predominantly non-renewable sources, as hydrogen power may do, are not genuinely renewable). Lack of sunshine and the low cost-effectiveness of current photovoltaic cell technology make solar power an ineffective short-term option, although improvements in solar technology will help. The UK is very well endowed with wind and waves and long-term energy supply from these looks promising. However: "In order to get more than 20% of electricity from renewables by 2020, build rates for the leading options would need to be at levels never before seen in the UK. Onshore and offshore wind would need to be installed at a rate of between 1-2 GW per year in the period 2010-2020" [The Energy Review, PIU, Feb 2002]. The space needed for onshore wind farms would also increase pressure on Britain's limited supply of land - see 11.1.2 below.

11.1 WIND POWER: UK

11.1.1 How much of our energy can wind provide?

Wind power is clean and carbon-free, and if the UK's offshore air currents remain as prevalent as they are today, it will remain the most promising proven source of renewable energy until technology innovations improve prospects for solar, wave and tidal power.

By mid-2006, according to the British Wind Energy Association (BWEA), 1,618 turbines with a rated capacity of 1,695 MW were operational in the UK, producing 510 MW of electricity a year (average turbine output is about 30% of rated capacity). These 1,618 turbines are described as able to 'power' 947,504 homes (see below). By 2010, with an additional 1,500 onshore turbines and 1,300 offshore, the BWEA hopes to have 8,000 MW of rated capacity available to electricity suppliers, providing 'at least 8%' of total electricity supply. But to achieve this 8% target, one turbine of at least 1.65 MW would have to be installed every day from now until 2010. With only 20% of household energy consumption used in the form of electricity, with households accounting for 29.5% of total energy consumption (see Chart 7.3.1) and with electricity accounting for only 17.5% of all final energy use (see Chart 7.2.3) it can be seen what a small fraction of total energy is being supplied by wind.

The wind industry, assuming a 35% average capacity factor, hopes that wind will be providing 78 TWh of electricity a year in 2020 (equal to a fifth of current electricity supply), and will be avoiding 32 million tonnes of CO2 emissions. The BWEA proposed, in its submission to the government's 2006 Energy Review, that a target of 25,200 MW of rated capacity should be installed by 2020. To build the extra 16,200 MW between 2010 and 2020, two turbines rated at 2.2 MW would need to be built every day for 10 years.

11.1.2 How much land would be needed to provide all our electricity from wind?

Again, it depends how much wind power can be constructed offshore. If half the 25,200 MW target for 2020 (estimated to provide a fifth of UK electricity) were built onshore, 3,100 square kilometres of land would be needed - an area larger than the whole county of Dorset (2,653 sq km). For wind power to supply all-electric homes at today's rates of consumption, for today's 60 million people, several counties would need to be covered with wind turbines. Turbines are being built to rated capacities above 1MW, but whatever the capacity of a turbine, and whatever the improvement in energy yield per hectare, these calculations apply only to household electricity demand - if wind power were to be used to produce hydrogen fuel cells as a substitute for petrol for motor transport, land requirements for turbines would rise further - in a country that is already more densely populated that China.

11.2 MARINE RENEWABLES UK: WAVE AND TIDAL ENERGY

The seas surrounding the UK provide two forms of clean energy which can be converted into electrical power - waves and tides, and there is no shortage of either. "The highest energy waves are concentrated off the western coast in the 40^o to 60^o latitude range north and south. The power in the wave fronts varies in these areas between 30 and 70 kW/m with peaks to 100kW/m in the Atlantic south-west of Ireland", according to the World Energy Council. As an island facing the turbulent Atlantic, the UK has one of the most promising sources of wave energy of any country in Europe.

Tidal power also promises much, and because tides rise and fall each day according to the gravitational pull of the Moon and Sun, tidal power stations would not suffer the same intermittency problems as wind power. The Carbon Trust estimates that harnessing UK tidal power could produce about 18TWh (terawatt hours) of electricity a year, and industry optimists expect 10-20 TWh to be onstream by 2020. Both wave 'farms' and tidal power stations are also likely to produce more electrical power per hectare of sea surface than wind can provide per hectare of land or sea: according to industry experts a 10 MW wave power station might in future fit into about 4 acres of ocean space.

However, as with other renewable energies, the promise has yet to become reality. The marine renewables industry lags the wind industry by about 15 years, and marine energy prototypes take up to 10 years to develop before the technology is proven and taken further to full commercial operation. Wave and tidal power technologies have been studied for decades, but by mid-2006 no wave or tidal power station has got to this stage. Two arrays of 10 1MW rotor turbines making up the Marine Current Turbines tidal power farm off Lynmouth, Devon, for example, are expected to reach commercial demonstration stage by 2009. With load factors of about 30-40%, the energy output from a 10MW rated tidal power project would typically be 26,000 to 35,000 MWh of electricity a year.

As with other renewables, the threefold increase in oil prices in six years is bringing investment capital into marine energy as the unit price at which it can deliver electricity becomes more competitive. The total operating cost of generating power from a 100MW wave station is projected at a competitive 4-6p/kWh per 100MW of primary power. But no wave or wind electricity is expected to be available for consumers before 2010. Not one light bulb in the UK is lit up by commercial wave or tidal electricity. Industry experts believe they have solved the problems of corrosion and contamination of turbine equipment; but engineering design, to prevent 'fatigue failure', maintenance costs, connection to inland electricity grids; competitively priced electricity output; and as yet unknown damage to ocean and seabed ecosystems are among the challenges to be overcome.

11.3 BIOENERGY: UK

Another form of renewable energy is bioenergy. This divides into two broad categories, with some overlap: (1) electrical power produced by biomass, such as electricity produced by burning SRC (short rotation coppiced) willow, poplar or miscanthus, straw or chicken litter or (b) biofuels: liquid fuels produced from oil-yielding plants such bioethanol from cereals and biodiesel from rapeseed oil. Heat can be produced as a by-product of electricity from wood biomass, and this energy is almost carbon neutral - it produces carbon dioxide emissions which are offset by the absorption of carbon dioxide during the growth period. Once again, however, low energy yields and the high land requirements associated with bioenergy mean that it cannot contribute much to the energy needs of a population with as little land per capita as the UK.

In the most comprehensive assessment of Biomass as a Renewable Energy Source for the UK, published by the Royal Commission on Environmental Pollution in January 2004, a target of up to 16GW of energy from biomass by 2050 is recommended, which would (at 16GW) then be 12% of a projected total 132 GW of energy required by the UK. To meet the 16GW target "about 70 million tonnes of wood per year [would be needed]. If all the wood was derived from energy crops at an average yearly yield of 10 odt (over-dried tonnes) per hectare, some 7 million hectares would be required. To put these numbers into context, there is currently some 17 million hectares of agricultural holding in the UK." The report also reveals that "less than 2,000 hectares of energy crops are currently being grown in the UK, producing around 17,000 odt of fuel a year."

As far as biofuels are concerned, the net energy yields per hectare are low. Ethanol, one form of liquid fuel that can be produced from biomass, has a significantly lower energy content than petrol. Another example, rapeseed oil, is generally accepted to need one hectare to yield 3-5 tonnes of rapeseed. The oil content is 40-45% of the rapeseed, so a hectare will yield 1.2-2.5 tonnes of rapeseed oil, or 1,300-2,470 litres per hectare. If a barrel holds 205 litres, a hectare would produce 10 barrels of rapeseed oil.

A 2006 feasibility study by the National Farmers' Union on the Renewable Transport Fuel Obligation, a mechanism to compel road transport suppliers to provide 5% of their fuels by volume in the form of biofuels, concluded that by 2050, with advances in technology, "the UK could produce as much as one third of its transport energy needs from biomass". (In summer 2005, according to the NFU, biofuel sales were just 10 million litres a month.) This would, however, take up a fifth of UK arable land as defined by the EU single farm payments system - 1.2 million hectares of the 5.9 mha of arable land currently used for producing crops, plus grassland less than five years old and set-aside land. The land take would split between 375,000 ha for bioethanol production for petrol and 840,000 ha for biodiesel to combine with diesel.

This would be an encouraging start, and yields will rise sharply if technical problems such as the breakdown rate of ligno-cellulose in cellulose crops are solved. But if it takes 1.2 million ha to produce just 5% of the UK's road transport fuel, every square centimetre of the country would have to be covered with crops just to satisfy total 2010 demand. Road transport fuel accounts for only a quarter of all forms of energy consumed, the productivity of land used for bioenergy crops will be affected by climate change, and the UK will not only need its rapidly diminishing supply of non-urbanised land for other energy sources such as wind farms, but to produce food for an additional 10 million inhabitants expected in the UK by 2074.

Biomass crops which replace carbon-absorbing crops already grown on agricultural land do not raise ecologically necessary carbon absorption levels - to alleviate emissions damage, biomass crops should be grown on previously urbanised land. Yet successive governments, by their pro-population growth policies, have ensured continuous urbanisation in the UK, with progressive loss of ecologically productive land. For more details see research papers in the OPT Journal.

11.4 HYDROGEN POWER: UK

Misunderstandings about hydrogen power have led to over-optimism about its capacity to provide a clean and cheap alternative to liquid fossil fuels - mainly petrol for motor transport. Hydrogen is not a source of energy, but a carrier of energy, and production of energy from hydrogen requires inputs of either fossil fuels, nuclear or renewable energy. To use fossil fuels to provide hydrogen-powered cars would be self-defeating for both economic and environmental reasons. Producing hydrogen power from wind power or nuclear power would require impossibly high inputs in terms of turbines or power stations. See a series of papers on hydrogen power and renewables in the OPT Journal .

Brief calculations by Andrew Oswald, Professor of Economics at Warwick University, and Jim Oswald, a Chartered Engineer, suggest that to replace the fossil fuel currently burned in car engines in the UK by hydrogen would require either about 100,000 new wind turbines, or about 100 nuclear power stations. "If sited offshore, this would mean an approximately 10-kilometre-deep strip of wind turbines encircling the entire coastline of the British Isles. If sited on-shore then an area larger than Wales would have to be given over to wind turbines. Professor Oswald's calculations include an optimistic 50% capacity factor for wind turbines. See Professor Oswald's figures in The Arithmetic of Renewable Energy, [Accountancy Magazine, 5 October 2004].

FOOTNOTE

* Total UK final energy consumption by final user(Chart 7.3.1) = 159.5 Mtoe = 2.65 tonnes per capita (population 60.2 million). The 159.5 Mtoe refers to total energy supplied, without taking account of whether it comes in the form of electricity or just heat. About 20% is in the form of heat generated by uranium or fossil fuels, so an edditional 70Mtoe of thermal energy is consumed in order to supply the 161 Mtoe (AF).

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Briefing by Rosamund McDougall, Advisory Council, Optimum Population Trust

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This website launched June 2002
Items last updated 7 June 2007