With SA’s involvement in pebble bed reactor developments there may be some good opportunities for the local I&C industry.
In an article published last year in SA I&C the safety of the nuclear power industry was reviewed and the conclusion reached was that electricity generated by such means would remain essentially along with more traditional and environmentally friendly methods. The biggest threat to safety was seen in allowing new nuclear powers to follow their own path as they might have to relearn the lessons gained from disasters such as Three Mile Island, Windscale (Sellafield) and Chernobyl. In this article we look at current world trends in the use of nuclear power to generate electricity, bearing in mind that a lot has been learned since the early developments and accidents, and that modern control systems are very much more advanced that those used in the early days of nuclear power. Today's advanced control systems are also designed to eliminate the possibility of human error which led of course to the Chernobyl disaster.
Global warming concerns
The world, including the United States, is growing concerned regarding global warming which many scientists believe is caused mainly by the emission of greenhouse gases such as CO2. A recent report (August 2005) by the BBC indicated that Europe's big cities are getting hotter faster than expected. London as one example has an average maximum temperature that is two degrees higher than in the 1970s. The only way to curb global warming is through the reduction of greenhouse gases and for industrialised nations this means moving away from fossil fuel generation of electrical power. Although there has been great hype about re-usable energy (wind, solar, etc) this will never solve the problem (in terms of both capacity and the need for base-load) and its implementation has been minimal. Generation of solar power in Europe would only be possible during summer months and a recent article indicated that even if it was feasible (in say the south of France) installation of solar cells would be 36 times more expensive than nuclear energy. To replace all of the EU's nuclear plants with wind turbines would require them to cover an area of 32 000 km2 and even then what happens when the wind does not blow. Hydroelectric power is also being viewed in a negative light following the Chinese Three Gorges project which will see almost two million people displaced. Other programmes such as that operated by Eskom to reduce use of electricity through for example more energy efficient light bulbs will have only a limited benefit as world economies continue to grow and demand more electrical power.
No choice
The only viable option given the growing use of electricity by industry and domestic users is through the expansion of the nuclear option, the likelihood of which by the way has resulted in many South African mines pursuing uranium for the first time in years. The anti-nuclear lobby also does not realise the size of the world's nuclear energy programme. In fact, at the end of 2004 there were 441 nuclear power plants operating in some 31 countries making a significant contribution to the reduction of the world's CO2 emissions. These plants are supplying 16% of the world's energy or about 364 000 MW. In addition to these power generation reactors some 56 countries are operating a total of 284 research reactors.
America's nuclear power programme
The largest single user of nuclear power in the world is the United States and as of April 2005 there were 104 nuclear reactors operating and generating some 97 400 MW, providing about 20% of that country's energy needs. The USA uses two types of reactor, pressurised water reactors (69) and boiling water reactors (35). These reactors are distributed between 31 states with Vermont having some 74% of its electricity generated by nuclear power while several other states exceed 50%. The oldest reactor still in operation came on-line in 1970 while the last reactor to be commissioned was the Watt's Bar reactor in May 1996. The USA has used four manufacturers for its reactors, these being General Electric, Westinghouse, Framatome ANP and ABB. ABB's nuclear business was acquired by Westinghouse during 2000. The boom period for the construction of nuclear plants was from 1973 to 1990, after that total nuclear capacity has remained virtually unchanged. Note, however, that the Three Mile Island incident occurred in 1979 and that did not stop the pace of nuclear development.
The current administration is supportive of nuclear expansion, emphasising its importance in maintaining a diverse energy supply. As of April 2005 no US nuclear company had applied for a new construction permit. With projected increases in electricity demand the construction of new plants or the re-activation of shut down reactors is receiving attention. A third option being considered is uprating existing units to generate more power. Although such uprates are usually less than 10%, the increase would be significant in terms of the total power being generated.
Despite the lack of construction both General Electric and Westinghouse have new advanced designs and the USA is also working on 4th generation technology.
The French nuclear power programme
Unlike other Western nations which virtually abandoned the construction of new nuclear plants in the '60s and '70s, France continued to adopt the technology. Initially the French government decided in 1974, just after the first oil price shock, that this was the way to retain its independence in terms of low-cost power generation. Today France has some 59 nuclear reactors operated by the EdF and these produce up to 80% of its electricity demand. The continued development of the French nuclear programme has ensured that many of its newer stations are state-of-the-art. Although there have been several minor problems with plants, France has never reported a serious accident. France by the way is also the world's largest net electricity exporter, with consumers including Italy and the UK.
The first French reactors were of gas-cooled type, but today apart from one experimental fast breeder reactor all the operating French units are pressurised water reactor (PWR) types, three variations being offered by Framatome. In conjunction with German company Siemens, France has recently developed the European Pressurised Water Reactor (EPR) which received design approval in 2004 and will become the new standard design for France. The reactor being built in Finland (see below) is an EPR unit and the first French system is expected to come on-line in 2012. The EPR is being marketed as a third generation reactor. Standardisation on one type of reactor for France meant that plants were much cheaper to build while the lessons learned from an incident at one plant could be quickly learned by the managers of the others. Decommissioning is not seen as a problem for France and 11 power and experimental reactors are currently being dismantled. It should also be noted that in France (unlike the USA, the UK and most of Europe), nuclear power is well accepted and people in the immediate vicinity of plants have been encouraged with the provision of new jobs and prosperity.
France has also used its expertise to build a large number of nuclear power plants in other countries throughout the world. Countries with French-designed plants in operation include Argentina, Brazil, China, South Korea, Belgium, Germany, Spain, South Africa, the Netherlands and Switzerland. One of its more recent projects is the building of a 1600 MW reactor in Finland that is designed to come on stream in 2009. This will be Finland's fifth reactor.
Fusion development in France
While all existing reactors use the process of fission there is great interest in pursuing the long-term goal of a fusion reactor. The United States, Japan, the European Union, Russia, China and South Korea have joined forces in a $13 billion programme to develop such a reactor. After much deliberation France has been chosen as the site for the new development. Despite comments to the contrary this shows the continued interest in nuclear power. It is expected that the fusion reactor could take ten years to build and it could be 50 years before the technology becomes commercially viable.
Besides its latest EPR design France is also working on a fourth generation reactor, the very high temperature reactor (VHTR). It is also expected that it will work very closely with the United States in the development of next generation nuclear plant technology.
The British nuclear power programme
After the United States the next country to become a nuclear power was the United Kingdom which also claims to be the first country in the world to adopt nuclear power on a commercial basis when it opened the Calder Hall plant in 1956. The first generation reactors were called Magnox reactors and two were built outside the UK in Japan and Italy. The Magnox reactors were followed by a series of advanced cooled reactors (ACR) commissioned between 1976 and 1988 with a pressurised water reactor being commissioned in 1995. In total, 19 nuclear power stations comprising 41 reactors were constructed. Today, only eight nuclear power stations are in operation and by 2011 only two will remain operational. British policy on the future of nuclear energy is confusing in that it was decided in a 1994 review that the future use of the technology was not economically viable (that was before the spike in oil prices). A report published in April 2005 however states that advisors to Tony Blair had suggested that the best way to meet the country's targets of reduced emission of gases would be to construct new nuclear power stations.
Most European countries with the exception of Italy possess nuclear power plants but the future in some of these countries seems unclear.
Sweden
Sweden commissioned its first small heavy water reactor in 1964 and by 2005 had 10 reactors in operation that provide half of its electricity, but a referendum held in 1980 following the Three Mile Island incident resulted in the termination of its nuclear programme and the understanding that the existing reactors would be phased out when they reached the end of their lives (2012 to 2025). Since 1980 the focus in Sweden has been on greenhouse gas emission and new sources of nuclear energy could come back on the table, particularly with developments in the inherently safe pebble bed technology.
Germany
Germany has 17 operating nuclear reactors which supply about one third of its electrical power. All of these reactors are of 'safer' Western design and following re-unification in 1990 all of the Soviet-designed reactors operating in the East (five) were shut down. Again, although having a very good safety record a coalition government formed in 1998 had the phasing out of nuclear reactors as part of its policy. A compromise was reached in 2001 and under this agreement the operational lives of nuclear power plants will be limited to 32 years. The existing plants were commissioned between 1975 and 1989 before the nuclear power programme was abandoned. Germany may well have to review its policy as its other main fuel for base-load electricity is brown coal which is a significant contributor to CO2. Public sentiment in Germany has however swung strongly in favour of nuclear energy with 81% of the population wanting the plants to continue operating in a poll held in 1997 (as compared to a figure of 61% in 1991). There has also been strong cooperation between France and Germany on the development of the former's advanced reactor (the EPR). Two pebble bed reactors operating using thorium-based fuel operated between 1967 to 1988, and 1985 to 1988. These proved the basic pebble bed technology which is today being further developed by China and South Africa.
Anti-nuclear referendums
In contrast to Sweden and Germany other western European countries seem ambivalent regarding nuclear power although in Switzerland two anti-nuclear referendums were comfortably defeated. With the expansion of the EU to the East there are now 151 nuclear power plants within the enlarged Europe providing 32% of the power generated. Despite current policy the governments of Sweden, Britain and Belgium are again debating the role to be played by nuclear power in the future and a similar debate is likely to take place in Germany in the near future.
The Canadian nuclear power programme
Canada supplied its first electricity derived using nuclear energy in 1962. The plant used local technology developed between 1955 and 1958 and referred to as CANDU-PHW (Canadian deuterium uranium - pressurised heavy water). Today all of Canada's nuclear power plants use this technology which uses natural uranium fuel and heavy water. The technology is also sold to other countries and there are operating CANDU reactors in Pakistan, China, India, Argentina, South Korea and Romania. In 2002 there were 32 CANDU reactors operating throughout the world, the last one having been commissioned in China that year.
Today, Canada's power utilities operate five nuclear power plants containing 17 CANDU reactors and another three reactors are scheduled for re-start up. As an example of capacity nuclear power plants operated by Ontario Power Generation provide 38% of the electricity it generates and just one of these plants is providing about 20% of Ontario's electricity needs.
The Japanese nuclear power programme
Japan is another fuel short country and while possessing some coal it has to import substantial amounts of crude oil, natural gas and other energy resources. Despite being the only country in the world to experience the horror of nuclear weapons the first oil crisis saw it look to nuclear power as the long term answer to its electrical demand supply. Japan imported its first Magnox reactor from the UK and this operated successfully from 1966 until 1998. After this only light water reactors (LWRs), boiling water reactors (BWRs) and pressurised water reactors (PWRs) were constructed. Initially the Japanese utilities purchased designs from US vendors and built them using Japanese companies. By the end of the 1970s the Japanese industry had established its own design capability and today it sells to other Asian countries and is involved in new reactor designs that may be used in Europe.
Although there have been some safety incidents in Japan its nuclear programme continues unabated. Today its installed capacity is some 47 700 MW from a total of 55 reactors. A further two reactors are under construction (2241 MW) while planned or on order units total 11 which will contribute a further 13 407 MW. Japan also has in place a plan to develop its own fast breeder reactor which could come on-line by 2015. The Japanese plan is to have 42% of its electricity generated from nuclear plants by 2010 (from 34% in 2005), and the country ranks third worldwide in installed nuclear capacity, behind the United States and France.
South Africa's nuclear power programme, the PBMR and its derivatives
South Africa developed its own experimental nuclear reactor, the Safari, but this was never intended to be connected to the grid. Today the Safari is used mainly to produce useful medical and other radio-isotopes. The first and only nuclear commercial plant is located at Koeberg and is of French design and France assisted in the construction.
Our nuclear future lies in the development of the advanced pebble bed modular reactor (PBMR) which is based on proven German technology although greatly enhanced with local design inputs. The South African PBMR because of its unique features is a particularly competitive option for a niche sector of electricity generation. The PBMR falls into the category of a high-temperature gas cooled reactor (HTR) and here it is not without competition. The Chinese also had access to the original German technology and already have a small 10 MW prototype PBMR running. Their technology is however believed to have not significantly changed from the original German work and in fact both countries (China and South Africa) have signed a memorandum of understanding on cooperation in the development of PBMR technology. Eskom has two major partners in the development; these being British Nuclear Fuel and the IDC, and more international partners are expected. A major feature of the PMBR is that it is inherently safe and does not need the safety features and control systems associated with conventional power plants. Another important feature is that spent fuel can be stored beneath the plant so that no hazard exists outside the site boundary.
Another competitor in the modular HTR reactor development is a gas turbine modular helium reactor being developed by an international consortium that includes the US and Russia. This makes use of prismatic fuel elements (as opposed to the easier to feed spheres used by both South Africa and China). Japan has also an operational prototype prismatic reactor running.
The niche that all of these developments fill is based on the use of the word 'modular'. It is intended that an individual reactor will be small, a commercial South African PBMR being rated at about 400 MW. However the South African design envisages that the reactor itself can be configured into 2, 4, 6 and 8-pack layouts which will maximise the sharing of support systems. In the case of Eskom most of its power is generated in the coal-rich north-east part of the country and transmission over vast distances is costly and results in power losses. Our conventional nuclear plant located at Koeberg needs sea water as its cooling mechanism whereas the PBMR using helium cooling can be located in virtually any secure site. An 8-pack system could generate up to 3200 MW and these reactors could be located close to existing or new industrial development zones. The PBMR company believes that Eskom alone could make use of up to 24 modular reactors and although much of the equipment for the development model will be purchased overseas, plans are in place to transfer this technology to local engineering companies. With potential exports running into the hundreds this could become a significant industry with major implications in terms of direct and indirect job creation and significant investment in the development of new skills. It has been estimated that if as few as 10 modules per year were to be exported this would contribute up to R8 billion to GDP, earn R10 billion per year in exports and create 57 000 direct and indirect jobs. The manufacture of these PBMRs will also generate significant business for the local instrumentation and control industry.
For South Africa itself, heavily dependent on coal-fired capacity, the PBMR may be the only long term solution to the reduction of greenhouse gas emissions.
Dr Maurice McDowell has many years' experience as a technical journalist, editor, business manager and research scientist. His third party analyses of world-class companies and processes, as well as his insight into industry and technology trends are well respected.
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