World Energy Needs and Nuclear Power
(12 November 2008)
- The world will need greatly increased energy supply in the next 20 years, especially cleanly-generated electricity.
- Electricity demand is increasing much more rapidly than overall energy use and is likely to almost double from 2004 to 2030.
- Nuclear power provides over 15% of the world's electricity, almost 24% of electricity in OECD countries, and 34% in the EU. Its use is increasing.
- Nuclear power is the most environmentally benign way of producing electricity on a large scale. Without it most of the world would have to rely almost entirely on fossil fuels for continuous, reliable supply of electricity.
- Renewable energy sources other than hydro have high generating costs but are helpful at the margin in providing clean power.
Primary energy and electricity (OECD World Energy Outlook 2008 reference case)
From 1980 to 2006 total world primary energy demand grew by 62%, and to 2030 it is projected to grow at a slightly lesser rate (45%, average 1.6% per year, from 491 EJ to 712 EJ). Electricity growth is even stronger, and is projected to almost double from 2006 to 2030 (growing at average 2.6% per year from 18,921 TWh to 33,265 TWh). Increased demand is most dramatic in developing countries and that is projected to increase, as the following graph indicates. Currently some two billion people have no access to electricity, and it is a high priority to address this lack.
With the United Nations predicting world population growth from 6.5 billion in 2006 to 8.2 billion by 2030, demand for energy must increase substantially over that period. Both population growth and increasing standards of living for many people in developing countries will cause strong growth in energy demand, expected to be 1.6% per year, or 45% from 2006 to 2030.
Nuclear power generation is an established part of the world's electricity mix providing over 15% of world electricity (cf. coal 40%, oil 10%, natural gas 15% and hydro & other 19%). It is especially suitable for large-scale, continuous electricity demand which requires reliability (ie base-load).
The World Energy Outlook 2008 from the OECD's International Energy Agency (IEA) highlights the increasing importance of nuclear power in meeting energy needs while achieving security of supply and minimising carbon dioxide emissions. The 2006 edition of this report warned that if policies remain unchanged, world energy demand to 2030 is forecast to increase by 53% accompanied by supply crises, giving a "dirty, insecure and expensive" energy future which is unsustainable. Over 70% of the increased energy demand is from developing countries, led by China and India - China will overtake the USA as top CO2 emitter by 2010.
The report demonstrates that nuclear power could make a major contribution to reducing dependence on imported gas and curbing CO2 emissions in a cost-effective way, since its uranium fuel is abundant. However governments must play a stronger role in facilitating private investment, especially in liberalized electricity markets where the trade-off between security and low price has been a disincentive to investment in new plant and grid infrastructure. The 2008 IEA report said that investment of US$ 26 trillion is required by 2030 under the reference scenario, and $6.5 trillion more under an alternative low-carbon energy scenario. Under this, nuclear capacity increases 85% to 680 GWe and energy demand reduces by some 10% and CO2 emissions reduce by 27% compared with 2006. Of the $26 trillion amount, $13.6 trillion is for electricity: about half for generation and the rest for transmission and distribution.
The International Atomic Energy Agency (IAEA) revised upwards its projections for 2030 in its annual Energy, Electricity and Nuclear Power Estimates for the Period to 2030 published in September 2008. Its low projection shows an increase from 372 GWe today to 473 GWe in 2030, the high one gives 748 GWe then, in line with forecast growth in power generation. The rising costs of natural gas and coal, together with energy supply security and environmental constraints, are among the factors contributing to anticipated nuclear growth.
The OECD's Nuclear Energy Agency published its first Nuclear Energy Outlook in October 2008. Apart from nuclear being virtually carbon-free, it points out that energy security is enhanced due to nuclear fuel's high energy density, which means that transport is less vulnerable and storage of large reserves is easy. In the NEO high scenario, life extensions and plant upratings continue and present plans for new capacity are largely implemented to 2030. After that new build accelerates to bring over 50 GWe on line each year, giving 1400 GWe nuclear capacity in 2050. It identifies factors which would result in that outcome. In the low scenario, new plants replace retirements to 2030 with some uprating and life extension, and expansion is then modest, resulting in only 600 GWe operating in 2050, compared with today's 373 GWe.
The US Energy Information Administration also revised upwards its normally low projections in its annual International Energy Outlook 2008: to 498 GWe in 2030. This is 34% higher than its 2030 projection published five years earlier.
The World Nuclear Association introduced Nuclear Century Outlook projections for nuclear growth based on country by country assessments extending to 2100. These projections, which will be regularly updated, appear on the WNA website. For each country, two projections are made, using optimistic and pessimistic assumptions. When added, the projections provide high and low "boundaries" for likely future global nuclear capacity. For 2030 the boundaries are 550 GWe and 1200 GWe. The Outlook also aims to identify what would be required to achieve a worldwide change to clean energy and to assess how much nuclear power could contribute to this. It envisages the capacity needed for full transformation of electricity to be emissions-free plus much greater use of electricity in transport. It also envisages greater use of electricity or clean heat for industrial processes including desalination, synthetic oil and hydrogen production, though most of this beyond the 2030 time frame.
Generation options
The renewable energy sources for electricity constitute a diverse group, from wind, solar, tidal and wave energy to hydro, geothermal and biomass-based power generation. Apart from hydro power in the few places where it is very plentiful, none of these is suitable, intrinsically or economically, for large-scale power generation where continuous, reliable supply is needed.
Growing use will however be made of the renewable energy sources in the years ahead, although their role is limited by their intermittent nature. Their economic attractiveness is still an issue also. Renewables will have most appeal where demand is for small-scale, intermittent supply of electricity. In the OECD about 2% of electricity is from renewables other than hydro and this is expected to increase to 4% by 2015.
This diagram shows that much of the electricity demand is in fact for continuous 24/7 supply (base-load), while some is for a lesser amount of predictable supply for about three quarters of the day, and less still for variable peak demand up to half of the time. With overnight charging of electric vehicles it is easy to see how the base-load proportion would grow, increasing the scope for nuclear and other plants which produce it.
Without nuclear power the world would have to rely almost entirely on fossil fuels, especially coal, to meet electricity demands for base-load electricity production. There is as much electricity generated by nuclear power today as from all sources worldwide in 1960.
Greenhouse Gases
On a global scale nuclear power currently reduces carbon dioxide emissions by some 2.5 billion tonnes per year (relative to the main alternative of coal-fired generation, about 2 billion tonnes relative to the present fuel mix). Carbon dioxide accounts for half of the human-contributed portion of the global warming effect of the atmosphere.
The UN Intergovernment Panel on Climate Change (IPCC) has comprehensively reviewed global warming and has reached a consensus that the phenomenon is real and does pose a significant environmental threat during the next century if fossil fuel use continues even at present global levels. See also Global Warming - science paper.
The 2007 IPCC report on mitigation of climate change says that the most cost-effective option for restricting the temperature rise to under 3°C will require an increase in non-carbon electricity generation from 34% (nuclear plus hydro) now to 48 - 53% by 2030, along with other measures. With a doubling of overall electricity demand by then, and a carbon emission cost of US$ 50 per tonne of CO2, nuclear's share of electricity generation is projected by IPCC to grow from 16% now to 18% of the increased demand (ie 2650 TWh to some 6000 TWh/yr), representing more than a doubling of the current nuclear output by 2030. The report projects other non-carbon sources apart from hydro contributing some 12-17% of global electricity generation by 2030.
These projected figures are estimates, and it is evident that if renewables fail to grow as much as hoped it means that other non-carbon sources will need to play a larger role. Thus nuclear power's contribution could triple or perhaps quadruple to more than 30% of the global generation mix in 2030 - around 10,000 TWh.
Nuclear power has a key role to play in reducing greenhouse gases. Every 22 tonnes of uranium (26 t U3O8) used saves one million tonnes of carbon dioxide relative to coal.
Use of Natural Resources
Carbon and hydrocarbon resources have many other uses that generating power on a large scale. Coal and other fossil fuels are required in a much larger quantities than uranium to produce the equivalent amount of electricity. Nuclear power already has substantially reduced the use of fossil fuels. There are particular questions of ethics and opportunity cost in the use of gas to generate base-load power.
A further aspect of natural resource use in some places is regarding fresh water. Coal-fired plants are often built on coalfields for logistical reasons, and then cooled with fresh water using evaporative cooling towers. These use a lot of water. With nuclear plants, there is no similar siting consideration and they may more readily be put on the coastline, using seawater for cooling without evaporation. In Australia, a dry continent, a move from coal-fired to nuclear power could save enough fresh water to supply a city of four million people.
See also Sustainable Energy in this series.
See also: Education brochures Sustainable energy: Uranium, Electricity and Climate Change, and Energy for the World - Why Uranium?
Sources
as quoted.