Japan accident and nuclear renaissance
Research activities leading to the generation of electricity from nuclear began with the discovery of radioactivity by the French scientist, Henri Becquerel in 1896. A major milestone was recorded by two German scientists, Otto Hann and Fritz Strassman in 1938. They provided the first documentary evidence of the splitting of a heavy nucleus from the […]
Research activities leading to the generation of electricity from nuclear began with the discovery of radioactivity by the French scientist, Henri Becquerel in 1896. A major milestone was recorded by two German scientists, Otto Hann and Fritz Strassman in 1938. They provided the first documentary evidence of the splitting of a heavy nucleus from the capture of neutron, which is accompanied by the release of a large amount of energy (i.e. nuclear fission). Realizing the significance of this feat, Enrico Fermi and others built the first artificial nuclear reactor in an abandoned underground squash court at the University of Chicago, USA. The nuclear reactor codenamed the Chicago Pile-I (CP-I) is thus the first man made, self-sustainable, nuclear fission, chain reaction system. However, some French researchers working in Africa, specifically in Oklo, Gabon had discovered that a natural nuclear reactor had been operational, about two billion years ago. Evidence had shown that, the relative concentration of the light isotope of uranium (i.e. U-235) at that time was substantially higher and that nuclear fission chain reaction in a mixture of natural uranium and ordinary water could have occurred. According to the findings, the contemporary U-235 concentration exceeded 3%. The discovery of a natural reactor at Oklo, Gabon was called the “Oklo phenomenon”.
The generation of electricity from nuclear reaction was triggered by the quest for military applications, which led to the detonation of the first atomic/nuclear bomb on Hiroshima and Nagasaki, Japan in 1945. Sixty six years later, the release of large inventory of radioactivity to the environment was again witnessed in Japan following the Fukushima disaster. In the early 50’s, the US Navy had operated the first nuclear powered sub-marines. Following this development, the first nuclear reactor to produce electricity on commercial basis was built in Obninski, Russia in 1954. It should be noted that the growth of the nuclear power technology did not go directly from the first critical fission chain reaction in 1942 to the first Generation of NPPs (i.e. Generation I reactors) in the 50s and 60s. Several technologies had emerged as a result of lessons learned. Prominent among them is the Pressurized Water Reactor (PWR) technology, which was adopted by the US Navy to power sub-marines. Another technology is the Boiling Water Reactor (BWR), the technology adopted for the NPPs at Fukushima Daiichi. Recently, Small Modular Reactor (SMR) technologies were initially developed for water desalination, but are being considered for small grid power systems. Of all the technologies, the PWR account for over 60% of operating power plants and over 80% of planned NPPs in the world. South Africa is the only African country with two units of NPPs supplying 1800MW of electricity to the national grid.
Considering the life span of the first generation of NPPs to be approximately 60 years, the Generation I reactors designed in the 50s and 60s are gradually approaching their life end (EOL). In the 70’s, the Generation II and III reactors, were developed in response to the oil crises at that time. They are still in operation and are safer and more efficient than Generation I. The Generation III+ reactors are being built and are designed with passive safety systems, and are to use mixed oxide (MOX) fuel. The proposition to combine nuclear fission and fusion reactions in a single design is called the Generation IV reactor. It is the so-called “hybrid” system designed to be economic, safe, proliferation resistant and would generate minimum waste. It is to come on board in about 30 years time. With regards to proliferation resistant qualities, research activities are focused on the use of Thorium (Th) rather than Uranium (U) as fuel. Thorium is globally acceptable, because compared to U, it is more plentiful and cannot be used to fashion a nuclear explosion without further nuclear transmutation.
Before the nuclear accident at Fukushima Daiichi, there was resurgence in the quest by countries with advanced programmes and newcomer nations to add nuclear to their energy mix – the nuclear renaissance. The newcomer nations in African countries, including Nigeria opted to join the global nuclear renaissance for obvious reasons. Following the accident, the prospects became much more uncertain and some countries made drastic political decisions. Notable anti-nuclear countries, Germany, Switzerland and to some extent, Italy decided to either phase out nuclear power entirely or abandon plans to build new plants. However, majority of the nuclear community re-affirmed their interests to continue with the nuclear power programmes. This is because the factors that had driven nuclear renaissance before Fukushima remain imperative for many countries. These factors are: growth in global energy demand; concerns about climate change and environmental issues with the use of fossil sources; problem of security of energy supply becoming prominent on the political agenda; and reliability of energy supply at affordable and predictable rates. In the light of the above, the impact of Fukushima can be described as critical, but has not significantly affected nuclear renaissance, now and probably, not in the near future. In my opinion, Nigeria, like emerging nuclear nations like Turkey, UAE, Vietnam to mention a few, needs to affirm commitment to its nuclear power programme as it may be the only environmental friendly alternative source of the future. Perhaps, we should emulate the South Korean example, from the first turn-key project, to technology domestication and beyond. The Korean programme began in 1958, with the country’s GDP put at US $82 and a total installed capacity of 280 MW and with no nuclear in the energy-mix. Recently, the South Korea’s nuclear industry has reached a level, whereby, NPPs are being exported. The country’s GDP is over US $ 20,000 and the installed capacity is well over 70, 000MW, with nuclear accounting for close to 40%.
The deployment of nuclear power for electricity generation globally, has achieved good degree of success in spite of the Fukushima accident. It is still, and will continue to be part of the energy mix of the leading economies in the world. Even disregarding the nuclear renaissance in the world, but because of the acute power shortage in Nigeria, the nuclear option should be prominent in the nation’s energy mix in the medium and long term timelines.
Professor Jonah is with the Centre for Energy Research and Training, Ahmadu Bello University, Zaria