World Energy Needs and Nuclear Power (Updated August 2014) - TopicsExpress



          

World Energy Needs and Nuclear Power (Updated August 2014) The world will need greatly increased energy supply in the next 20 years, especially cleanly-generated electricity. Electricity demand is increasing twice as fast as overall energy use and is likely to rise by more than two-thirds 2011 to 2035. In 2012, 42% of primary energy used was converted into electricity. Nuclear power provides about 11% of the worlds electricity, and 21% of electricity in OECD countries. Nuclear power is the most environmentally benign way of producing electricity on a large scale. Renewable energy sources other than hydro have high generating costs but can be helpful at the margin in providing clean power. Primary energy and electricity outlook The World Energy Outlook 2013 from the OECDs International Energy Agency (IEA) sets out the present situation and also present current policies*, new policies, and carbon reduction (‘450’) scenarios. From 2000 to 2010 total world primary energy demand grew by 26%, and to 2020 it is projected to grow less (by 20% under current policies scenario, and less under other scenarios). Growth to 2035 is 45% under current policies, and 33% under a more restrained scenario. Electricity growth is about double this in each case. Electricity demand almost doubled from 1990 to 2011, and is projected to grow 81% from 2011 to 2035 (from 19,004 TWh to 34,454 TWh) in the current policies scenario, and 69% (to 32,150 TWh) in the central New Policies scenario. Increased demand is most dramatic in Asia, projected to average 4.0% or 3.6% per year respectively to 2035. Currently some two billion people have no access to electricity, and it is a high priority to address this lack. Electricity Information 2013 from the same source gives the latest available data on world electricity generation and its fuels. * The Reference case describes what would happen if, among other things, governments were to take no new initiatives bearing on the energy sector, beyond those already adopted by mid-2013. It is thus a baseline, not a forecast. With the United Nations predicting world population growth from 6.7 billion in 2011 to 8.7 billion by 2035, 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, as outlined above. Over 70% of the increased energy demand is from developing countries, led by China and India – China overtook the USA as top CO2 emitter in 2007. Superimposed on this, the UN Population Division projects an ongoing trend of urbanisation, from 52% in 2011 to 62% in 2035 and reaching 70% worldwide by 2050, enabling world population to stabilize at about 9 billion with better food supply, clean water, sanitation, health, education and communication facilities. Coal is not limited globally, but large amounts need to be moved from where it is plentiful to where it is needed, mainly for power generation. This has both economic and carbon emission implications (apart from actually burning it). Natural gas is abundant and increasingly traded over long distances, with supplies in several countries increasing due to technology enabling access to gas in shale beds. Oil is more limited, in 2012 global production increased to almost 76 million barrels per day (27 billion barrels/yr), and known reserves increased 8% to 1600 billion barrels. In the World Energy Outlook 2013 New Policies scenario, coal demand increases 0.7% per year from 2011 to 2035, gas increases 1.6% pa, and oil increases 1.1% pa to 2020 then 0.4% pa. For electricity, coal use increases 35% to 2035 thus reducing its share of generation from 41% to 33%, gas increases 72% so that its share remains at 22%, nuclear increases 66% pa to hold its 12% share, and renewables other than hydro increase 483%. World Electricity Consumption by Region Nuclear Power in published scenarios Nuclear power generation is an established part of the worlds electricity mix providing in 2011 some 11.6% of world electricity of 22,202 TWh (cf. coal 41.2%, oil 4.8%, natural gas 21.8%, hydro 16.1% and other 4.5%). It is especially suitable for large-scale, continuous electricity demand which requires reliability (i.e. base-load), and hence ideally matched to increasing urbanisation worldwide. The World Energy Outlook 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 remained 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 would be unsustainable. The report showed 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 needed to play a stronger role in facilitating private investment, especially in liberalized electricity markets where the trade-off between security and low price had been a disincentive to investment in new plant and grid infrastructure. The World Energy Outlook 2009 report said that investment of US$ 25.6 trillion* would be required by 2030 under the reference scenario, and $10.5 trillion more under an alternative low-carbon energy scenario. Under this, nuclear capacity increases 378 GWe (86%) to 816 GWe rather than to 475 GWe in reference case, energy demand increases by 20% rather than 40% and CO2 emissions reduce to 26.4 Gt/yr from 28.8 Gt/yr in 2007. * Of the $25.6 trillion amount, $13.7 trillion is for electricity: about half for generation and the rest for transmission and distribution. The World Energy Outlook 2010 report built on this and showed that removing fossil‐fuel consumption subsidies, which totaled $312 billion in 2009 (mostly in non-OECD countries), could make a big contribution to meeting energy security and environmental goals, including mitigating CO2 and other emissions. In the central New Policies scenario, based on recent policy advances, world primary energy demand increases by 36% between 2008 and 2035, or 1.2% per year average. This compares with 2% per year over the previous 27‐year period, but is higher than the low-carbon scenario. In this scenario, non-OECD countries account for 93% of the primary energy demand growth. The report notes that while Chinas energy use was half that of the USA in 2000, it overtook the USA in 2009. In the WEO 2010 New Policies scenario electricity demand was expected to grow at 2.2% pa to 2035, almost double the rate of primary energy, and with 80% of the growth being in non-OECD countries. Globally, gross capacity additions, to replace obsolete capacity and to meet demand growth, amount to around 5900 GWe to 2035 – 25% more than current installed capacity. Nuclear capacity increased by only 360 GWe, somewhat less than in the reduced carbon scenario. Support for renewable sources of electricity, estimated at $37 billion in 2009, is quadrupled. But per unit it drops from average 5.5 c/kWh to 2.3 cents, apart from costs of integrating them into the grid. CO2 emissions increase from 29 Gt/yr in 2008 to 34 Gt in 2020 and 35 Gt in 2035, all this being in non-OECD countries. In the low-carbon scenario they peak at 22 Gt about 2020 and drop to 22 Gt in 2035 with CO2 emission costs then being $90-120 per tonne (all in 2009 dollars). In the 450 low-carbon scenario to 2035, the additional spending on low‐carbon energy technologies (business investment and consumer spending) amounts to $18 trillion more than in the Current Policies Scenario, and around $13.5 trillion more than in the New Policies Scenario. Following the Fukushima accident, World Energy Outlook 2011 New Policies scenario had a 60% increase in nuclear capacity to 2035, compared with about 90% the year before. Although the prospects for nuclear power in the New Policies Scenario are weaker in some regions than in [WEO 2010] projections, nuclear power continues to play an important role, providing base-load electricity. Most non-OECD countries and many OECD countries are expected to press ahead with plans to install additional nuclear power plants, though there may be short-term delays as the safety standards of existing and new plants are reviewed. Globally, nuclear power capacity is projected to rise in the New Policies Scenario from 393 GW in 2009 to 630 GW in 2035, around 20 GW lower than projected last year. In this scenario the IEA expects the share of coal in total electricity to drop from 41% now to 33% in 2035. Electricity generation increases from 20 to 36 PWh. WEO 2011 also included a Low Nuclear Case (which) examines the implications for global energy balances of a much smaller role for nuclear power. The lower nuclear component of electricity supply is not a forecast, post Fukushima, but an assumption adopted for the purpose of illustrating a global energy outlook in such a low nuclear world. In the Low Nuclear Case, the total amount of nuclear power capacity falls from 393 GW at the end of 2010 to 335 GW in 2035, just over half the level in the New Policies Scenario. The share of nuclear power in total generation drops from 13% in 2010 to just 7% in 2035, with implications for energy security, diversity of the fuel mix, spending on energy imports and energy-related CO2 emissions. Its effect would be to increase import bills, heighten energy security concerns and make it harder and more expensive to combat climate change. The New Policies scenario in World Energy Outlook 2012 showed that several fundamental trends persist: energy demand and CO2 emissions rise even higher; energy market dynamics are increasingly determined by emerging economies; fossil fuels remain the dominant energy sources; and providing universal energy access to the worlds poor countries continues to be an elusive goal. Electricity generation increases from 21.5 PWh in 2010 to 36.6 PWh in 2035, with average price increase of 15% in real terms. WEO 2012 further reduced nuclear capacity projections for 2035, to 580 GWe, about 10% less than that scenario the year before and only 55% more than today. That would produce 4.37 PWh, 12% of world total. Renewables are likely to become the worlds second-largest source of power generation by 2015, with share of electricity generation growing from 20% in 2010 (mostly hydro) to 31% by 2035, though this hinges critically on continued subsidies which impact electricity prices. The IEA concluded that taking all new developments and policies into account, the world is still failing to put the global energy system onto a more sustainable path. This is highlighted by a 28% increase in fossil fuel subsidies to $523 billion in 2011 (compared with $409 billion in 2010, and $44 billion in 2010 for renewables. Renewables subsidies are expected to reach $240 billion per year in 2035, for 31% of power). World Energy Outlook 2013 was very much in line with WEO 2012, and electricity generation increases from 22.1 PWh in 2011 to 37.1 PWh in 2035. Its New Policies scenario showed 66% increase in nuclear contribution 2011-2035, with its share steady at 12%. Nuclear capacity rises only 47% however, in line with WEO 2012, with the expansion being mainly policy-driven on energy security grounds. The largest gross capacity additions are in China, which adds 114 GWe during the projection period (38% of global new nuclear capacity). Cumulative global investment in the power sector to 2035 needs to be $17 trillion, an average of $740 billion per year. New plants account for 58% of this, the rest is transmission and distribution. Electricity prices by 2035 are expected to show significant regional differences, with those for industry in USA ($80/MWh) being a little over half those in the EU and 40% lower than China’s, where network costs eclipse capital cost savings. Japan’s electricity prices for industry, now shown as over $185/MWh, decrease below EU levels to about $145/MWh as fossil fuel imports diminish. The 2012 IEA Energy Technology Perspectives Study (ETP 2012) took the 450 ppm scenario in WEO 2011 and extended it out to 2050, calling it the two-degree scenario (2DS). This scenario is then compared with the status quo (six-degree scenario) and with a four-degree scenario in between. It then goes a step further to see if a zero emissions energy system is possible by 2075. The study made the case that environment and energy development must go hand in hand. Some of the findings: A sustainable energy system is still within reach and can bring broad benefits Technologies can and must play an integral role in transforming the energy system. Investing in clean energy makes economic sense – every additional dollar invested can generate three dollars in future fuel savings by 2050. Energy security and climate change mitigation are allies. Despite technology’s potential, progress in clean energy is too slow Nine out of ten technologies that hold potential for energy and CO2 emissions savings are failing to meet the deployment objectives needed to achieve the necessary transition to a low-carbon future. Some of the technologies with the largest potential are showing the least progress. The share of energy-related investment in public research, development and demonstration (RD&D) has fallen by two-thirds since the 1980s. Fossil fuels remain dominant and demand continues to grow, locking in high-carbon infrastructure. It then goes on to focus on how energy policy must address the key issues and the role of government in formulating that, finally concluding with recommendations to energy ministers (assuming these recommendations were to be considered at Rio+20). The study focused on renewable technologies such as wind and solar, energy efficiency technologies to reduce demand, and carbon capture technologies to clean up the ever-expanding fossil infrastructure, though this is prime area where progress is obviously too slow. Nuclear technology is also shown to be important although its suggested role in ETP 2012 is less than the others. The electricity generation mixes for each of the three scenarios in 2050 range from almost 50,000 TWh in 6DS down to 40,000 TWh in 2DS. Improved energy efficiencies is the most important source of clean generation, along with huge growth in renewables (wind, solar, hydro and biomass) and an increase in nuclear output to about 8,000 TWh in 2DS. Most of the remaining fossil generation, contributing 10,000 TWh, is assumed to have CCS installed. Looking at the needed capacity, due to the variability and low capacity factors of renewables such as wind and solar, capacity must increase even more than the output. This demonstrates the importance of nuclear as it has high capacity relative to other forms of generation. With less than 5% of the generating capacity (about 550 GWe), it produces about 20% of the electricity, indicating its importance in a low-carbon electricity system. The main tool in achieving CO2 reduction targets for the 2DS is CO2 price, increasing from USD 40/tCO2 in 2020 to USD 150/tCO2 in 2050. This greatly increases the electricity generation costs of CO2-emitting technologies and thereby improves the relative cost-competitiveness of low-carbon power technologies. The report suggests that the only way to achieve a low-carbon world is to price carbon aggressively to force behavioural change; first by reducing demand and second through the implementation of higher cost low carbon technologies. This has a major impact on electricity prices, however, and the only mitigating factor is the relatively low cost of power from nuclear plants allowed to operate on a continuous full-power basis unrestrained by subsidised high-cost intermittent sources having dispatch preference. Hence the study continues to include a high nuclear sensitivity case for the 2DS scenario. In the 2DS-hiNuc case, nuclear generation is increased to 34% in 2050. Compared with the base 2DS, nuclear replaces fossil power plants with CCS and renewables, whose share in 2050 falls, in the case of CCS from 15% to 7%, and in the case of renewables from 57% to 49%. This scenario reflects a world with greater public acceptance of nuclear power. On the technical side, the average construction rate for nuclear power plants in the period 2011 to 2050 rises from 27 GW/yr in the base 2DS to 50 GW/yr. The cumulative investment costs of this case are only USD 200 billion higher than in the base 2DS and are more than offset by costs savings for fossil fuels in the order of USD 2000 billion (10 to 1). A system with about one-third of the generation provided by nuclear is achievable if the industry can overcome the major issue of public acceptance. It raises the question of whether the public will prefer very high electricity costs with a large increase in renewable generation, or a greater role from nuclear power involving a relatively modest increase in the number of plants. The 2014 Energy Technology Perspectives developed the ETP 2012 scenarios. In the 2DS one which is the main focus, the share of fossil fuels in global primary energy supply drops by almost half – from 80% in 2011 to just over 40% in 2050, and some 22 GWe of new nuclear generating capacity must be added annually by 2050. However, the IEA notes that global nuclear capacity is stagnating at this time and by 2025 will be 5% to 25% below needed levels, demonstrating significant uncertainty. It suggests that the high capital and low running costs of nuclear create the need for policies that provide investor certainty. The IEA estimates that an additional $44 trillion in investment is needed in global electricity systems by 2050. However, it says that this represents only a small portion of global GDP and is offset by over $115 trillion in fuel savings. The new estimate compares with $36 trillion in ETP 2012. This increase, partly shows something the IEA has said for some time: the longer we wait, the more expensive it becomes to transform our energy system. While clean energy technology deployment in emerging economies has rallied over the past year – making up for declines in the industrialized world – the overall picture of progress remains bleak, according to the IEA. It claims that Cost-effective, practical solutions can increase efficiency, moderate electricity demand and decarbonize almost all power generation by 2050. However, in order to attain this, the decision-making process needs to be revised, abandoning the short-term, siloed attitudes of the past, and embracing a longer-term systems approach that identifies synergies within all sectors of the energy system. A significant change from ETP 2012 is much reduced forecast use of CCS by 2020, and one-fifth less by 2050. Launching the ETP 2014 report, the IEA executive director said: Electricity is going to play a defining role in the first half of this century as the energy carrier that increasingly powers economic growth and development. While this offers opportunities, it does not solve our problems; indeed, it creates many new challenges. She added, We must get it right, but were on the wrong path at the moment. Growing use of coal globally is overshadowing progress in renewable energy deployment, and the emissions intensity of the electricity system has not changed in 20 years despite some progress in some regions. A radical change of course at the global level is long overdue. The International Atomic Energy Agency (IAEA) in its annual Energy, Electricity and Nuclear Power Estimates for the Period to 2050 published in September 2012 revised downwards its projections for 2030, as it had done the previous year following the Fukushima accident. Its low projection showed a nuclear capacity increase from 370 GWe then to 456 GWe in 2030, the high one gave 740 GWe then, in line with forecast growth in all power generation. For 2050 it tentatively estimated 470 to 1337 GWe respectively. That IAEA publication in September 2013 again revised downward the projections for 2030, to 435 GWe in 2030 for the low projection and 722 GWe for the high one then. For 2050 the figures were 440 and 1113 GWe. The 2014 version again reduces 2030 projections to 401 GWe (low) and 699 GWe for the high projection. For 2050 the figures were 413 and 1092 GWe in 2014. The low figures assume “significant declines in North America, Europe and the OECD Pacific, stagnation in Africa, some growth in Latin America, CIS and ASEAN and substantial expansion in the Middle East and non-OECD Asia” (i.e. including China but excluding Japan and South Korea). The OECDs 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 fuels high energy density, which means that transport is less vulnerable and storage of large reserves is easy. In its 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 June 2010 this NEO was supplemented by the joint NEA-IEA Nuclear Technology Roadmap, with scenario for cutting energy-related CO2 emissions by 50% by 2050. This would see 1200 GWe of nuclear capacity on line then, providing 24% of electricity (world production having grown from 20,000 TWh in 2007 to 41,000 TWh then). Nuclear power would then be the single largest source of electricity. If constraints on building new nuclear capacity were overcome, nuclear could provide 38% of electricity by 2050, and in this case the power would be 11% cheaper then. The roadmap saw nuclear as a mature technology which required no major technological breakthrough to achieve the projected growth. However, global industrial capacity to construct nuclear power plants will need to double by 2020 if nuclear capacity is to grow in the 2020s and beyond as projected. The Roadmap estimates the investment in nuclear power needed by 2050 to be almost $4000 billion: including $893 billion in China, $883 billion in USA and Canada, $615 billion in OECD Pacific (including Japan & Korea), $389 billion in India, and $330 billion in centrally-planned economies. The US Energy Information Administration (EIA) has also revised upwards its normally low projections for nuclear in recent editions of its annual International Energy Outlook (IEO). In 2010 it projected 558 GWe nuclear capacity in 2030 and 593 GWe in 2035. The 2030 figure is 53% higher than its 2030 projection published seven years earlier. The reference case for 2035 includes 66 GWe added in China, 23 GWe in India, 25 GWe in Russia and 12 GWe in the USA. It projected 4200 TWh from nuclear in 2030 and 4510 TWh in 2035. In 2013 these projections had increased to 4755 TWh in 2030, 5135 TWh in 2035 and 5492 TWh in 2040 (from 2438 TWh in 2012). In the EIA International Energy Outlook 2013, nuclear power and renewable energy are forecast to be the worlds fastest-growing energy sources from 2010 to 2040, increasing by 2.5% each year, driven by concerns about energy security and greenhouse gas emissions which support the development of new nuclear generating capacity. Factors underlying the IEO2013 nuclear power projections are mixed. They include the consequences of the March 2011 disaster at Fukushima, planned retirements of nuclear capacity in OECD Europe under current policies, and continued strong growth of nuclear power in non-OECD Asia. In November 2011 the World Energy Council (WEC) published a report: Policies for the future: 2011 Assessment of country energy and climate policies, which ranked country performance according to an energy sustainability index, meaning how well each country performs on three pillars of energy policy – energy security, social equity, and environmental impact mitigation (particularly low carbon emissions), or simply environmental sustainability. The five countries with the most coherent and robust energy policies included large shares of nuclear energy in their electricity fuel mix. The best performers, according to the report, are: Switzerland (40% nuclear), Sweden (40% nuclear), France (75% nuclear), Germany (30% nuclear prior to reactor shutdowns earlier 2011), and Canada (15% nuclear). The report said that countries wanting to reduce reliance on nuclear power must work out how to do so without compromising energy sustainability. In Germany this would be a particular challenge without increasing the reliance on carbon-based power generation since the renewable infrastructure currently does not have the capability to do so. The 2013 version of this WEC World Energy Trilemma report gave top rating to Switzerland, Denmark, Sweden, the United Kingdom and Spain as being the only countries that historically demonstrate their ability to manage the trade-offs among the three competing energy policy dimensions coherently. These all have, or depend upon, a high level of nuclear contribution. Germany had notably dropped down the list on energy security and sustainability criteria, as had France on energy security. Canada plunged from 2011 due to environmental sustainability, though at top on the other two. In December 2011 the European Commission (EC) published its Energy 2050 Roadmap, a policy paper. This was very positive regarding nuclear power and said that nuclear energy can make a significant contribution to the energy transformation process and is a key source of low-carbon electricity generation that will keep system costs and electricity prices lower. As a large scale low-carbon option, nuclear energy will remain in the EU power generation mix. The paper analysed five possible scenarios leading to the EU low-carbon energy economy goal by 2050 (80% reduction of CO2 emissions), based on energy efficiency, renewables, nuclear power and carbon capture and storage (CCS). All scenarios show electricity will have to play a much greater role than now, almost doubling its share in final energy demand to 36%-39% in 2050. The EC high-efficiency scenario would reduce energy demand by 41% by 2050 (compared with 2005); the diversified supply technologies scenario would have a combination of high carbon prices, nuclear energy and introduction of CCS technologies; a high-renewables scenario suggests they might supply 75% of total energy supply by 2050; a delayed CCS scenario has nuclear power would playing a major role; and a low-nuclear power scenario had coal plants with CCS providing 32% of total energy (ie 82-89% of EU electricity). The highest percentage of nuclear energy would be in the delayed CCS and diversified supply technologies scenarios, in which it would account for 18% and 15% shares of primary energy supply respectively, ie 38-50% of EU electricity. Those scenarios also had the lowest total energy costs. In January 2014 BP published its Energy Outlook 2035, which showed growth in primary energy demand to then at 2.0% per year to 2020 then 1.2% pa, but electricity demand growth is much higher and by 2035 accounts for 46% of primary energy. Nuclear energy output is expected to rise to 2035 at around 1.9% a year. China, India and Russia will together account for 96% of the global growth in nuclear power, while nuclear output in the USA and EU declines due to expected plant closures. Renewables are expected to continue to be the fastest growing class of energy, gaining market share from a small base as they rise at an average of 6.4% a year to 2035. Renewables share of global electricity production is expected to grow from 5% to 14% by 2035. Including biofuels, renewables are expected to have a higher share of primary energy than nuclear by 2025. Electricite de France (EdF) in about 2008 published forecast world figures for the period to 2020. These show 140 GWe of new capacity being built and 10 GWe decommissioned to give 480 GWe in 2020. Of the 140 GWe new build, almost 30% is in China, 15% is in India and 15% other Asia. Europe, Americas and Russia have about 12% each. A WNA report early in 2013, Inside the Black Box – Exploring the Assumptions within Nuclear Power Forecasting, examines several scenarios for electricity and for nuclear power supply and their basis. A 2014 comparison among several sets of projections from IEA (WEO 2013) and EIA (Outlook 2013) showed 2035 nuclear capacity figures ranging from 527 to 792 GWe, compared with 381 GWe in 2010 base year. The World Energy Council’s higher scenario was 751 GWe. Exxon Mobil and Shell projections for 2040 were comparable with those from EIA. On the basis of these, a doubling of nuclear capacity by 2040 emerges as being likely. Generation options In electricity demand, the need for low-cost continuous, reliable supply can be distinguished from peak demand occurring over a few hours daily and able to command higher prices. Supply needs to match demand instantly and reliably over time. There are number of characteristics of nuclear power which make it particularly valuable apart from its actual generation cost per unit – MWh or kWh. Fuel is a low proportion of power cost, giving power price stability, its fuel is on site (not depending on continuous delivery), it is dispatchable on demand, it has fairly quick ramp-up, it contributes to clean air and low-CO2 objectives, it gives good voltage support for grid stability. These attributes are mostly not monetised in merchant markets, but have great value which is increasingly recognised where dependence on intermittent sources has grown, and governments address long-term reliability and security of supply. 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. Load curve 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. Without nuclear power the world would have to rely almost entirely on fossil fuels, especially coal, to meet demand for base-load electricity production. Most of the demand is for continuous, reliable supply on a large scale and there is little scope for changing this. There is as much electricity generated by nuclear power today as from all sources worldwide in 1960. There is much made of comparisons with renewables. Aside from the obvious intermittency and non-dispatchability of renewables, the following comparisons of plant materials is interesting. Per MWe of installed capacity (disregarding capacity factors): Solar PV: 40 t steel, 19 t aluminium, 76 t concrete, 85 t glass, 13 t silicon. Wind: 118 t steel, 298 t concrete Nuclear (1970s plant): 36-40 t steel, 75-90 m3 concrete.* * Wind data from Vestas, Jan 2011, Life Cycle Assessment of electricity production from V112 wind turbine; solar PV: A Review of Risks in the Solar Electric Life-Cycle, by V.M. Fthenakis and H.C. Kim of Brookhaven National Laboratory; Per F. Peterson, Haihua Zhao, and Robert Petroski, Metal And Concrete Inputs For Several Nuclear Power Plants, University of California, Berkeley. Implications of Electric Vehicles Future widespread use of electric vehicles, both pure electric and plug-in hybrids, will increase electricity demand modestly – perhaps up to 15% in terms of kilowatt-hours. But this increase will mostly come overnight, in off-peak demand, so will not much increase the systems peak capacity requirement in gigawatts. Overnight charging of vehicles will however greatly increase the proportion of that system capacity to be covered by base-load power generation – either nuclear or coal. In a typical system this might increase from about 50-60% to 70-80% of the total, as shown in the Figures below. This then has significant implications for the cost of electricity. Base-load power is generated much more cheaply than intermediate- and peak-load power, so the average cost of electricity will be lower than with the present pattern of use. And any such major increase in base-load capacity requirement will have a major upside potential for nuclear power if there are constraints on carbon emissions. So potentially the whole power supply gets a little cheaper and cleaner, and many fossil fuel emissions from road transport are avoided at the same time. Load curve 2 Load curve (3) Drivers for increased nuclear capacity The first generation of nuclear plants were justified by the need to alleviate urban smog caused by coal-fired power plants. Nuclear was also seen as an economic source of base-load electricity which reduced dependence on overseas imports of fossil fuels. Todays drivers for nuclear build have evolved: Increasing energy demand Global population growth in combination with industrial development will lead to a doubling of electricity consumption by 2030. Besides this incremental growth, there will be a need to renew a lot of generating stock in the USA and the EU over the same period. An increasing shortage of fresh water calls for energy-intensive desalination plants, and in the longer term hydrogen production for transport purposes will need large amounts of electricity and/or high temperature heat. See first section above for recent projections. Climate change Increased awareness of the dangers and effects of global warming and climate change has led decision makers, media and the public to realize that the use of fossil fuels must be reduced and replaced by low-emission sources of energy, such as nuclear power, the only readily available large-scale alternative to fossil fuels for production of continuous, reliable supply of electricity. Security of Supply A major topic on many political agendas is security of supply, as countries realize how vulnerable they are to interrupted deliveries of oil and gas. The abundance of naturally occurring uranium makes nuclear power attractive from an energy security standpoint. Economics Increasing fossil fuel prices have greatly improved the economics of nuclear power for electricity now. Several studies show that nuclear energy is the most cost-effective of the available base-load technologies. In addition, as carbon emission reductions are encouraged through various forms of government incentives and trading schemes, the economic benefits of nuclear power will increase further. Insurance against future price exposure A longer-term advantage of uranium over fossil fuels is the low impact that increased fuel prices will have on the final electricity production costs, since a large proportion of those costs is in the capital cost of the plant. This insensitivity to fuel price fluctuations offers a way to stabilize power prices in deregulated markets. As the nuclear industry is moving away from small national programmes towards global cooperative schemes, serial production of new plants will drive construction costs down and further increase the competitiveness of nuclear energy. In practice, is a rapid expansion of nuclear power capacity possible? Most reactors today are built in under five years (first concrete to first power), with four years being state of the art and three years being the aim with prefabrication. Several years are required for preliminary approvals before construction. It is noteworthy that in the 1980s, 218 power reactors started up, an average of one every 17 days. These included 47 in USA, 42 in France and 18 in Japan. The average power was 923.5 MWe. So it is not hard to imagine a similar number being commissioned in a decade after about 2015. But with China and India getting up to speed with nuclear energy and a world energy demand double the 1980 level in 2015, a realistic estimate of what is possible might be the equivalent of one 1000 MWe unit worldwide every five days. A relevant historical benchmark is that from 1941 to 1945, 18 US shipyards built over 2700 Liberty Ships. These were standardised 10,800 dwt cargo ships of a very basic British design but they became symbolic of US industrial wartime productivity and were vital to the war effort. Average construction time was 42 days in the shipyard, often using prefabricated modules. In 1943, three were being completed every day. They were 135 metres long and could carry 9100 tonnes of cargo. See also the paper in this series: Heavy Manufacturing of Power Plants. Clean Air and 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 Intergovernmental 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 Climate Change – 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, nuclears 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 powers 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. Of more immediate relevance is clean air, and the health benefits of low pollution levels. A World Health Organisation (WHO) study published in 2011 showed that some 1.34 million people each year die prematurely due to PM10 particles – those less than 10 microns (μm) – in outdoor air. Outdoor, PM10 particles mostly originate in coal-fired power stations and motor vehicles, and indoors, residential wood and coal burning for space heating is an important contributor, especially in rural areas during colder months. WHO studied publicly-available air quality data from 1081 cities across 91 countries, including capital cities and those with populations of more than 100,000 people. The data used are based on measurements taken from 2003 to 2010, with most being reported for the period 2008-09. The WHO air quality guideline for PM10 is 20 micrograms per cubic metre (μg/m3) as an annual average. However, eleven cities exceeded 200 μg/m3 average, eg UlaanBaatar at 279 μg/m3, whereas most of the 490 cities below the guideline level were in North America. 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 much larger quantities than uranium to produce the equivalent amount of electricity – nuclear power is very energy-dense, an extremely concentrated form of energy – see Table below. 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.
Posted on: Thu, 11 Sep 2014 09:48:35 +0000

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