The case for nuclear energy?



In order to generate power in a plant, the dominant method used involves using fuel to heat water, which gives rise to pressurized  steam. The vapour produced is then harnessed to give rotary motion to turbines in the plant. As the turbines turn, their kinetic energy is connected to a generator, which changes it into electrical energy. The generator is ultimately connected to transformers and electricity cables, as they channel electricity into the power grid infrastructure. Dominant heating fuels used are, coal, oil, gas, and also nuclear. There are also other sources of power such as hydro-electricity, tidal waves, solar and wind, which do not use heating fuels. However, those remain less in capacity, when compared to the output of thermal (heat based) power plants. 

Currently, the world’s electricity generation mix is dominated by coal, which has a 36% stake. In the case of S.A, about 85% of electricity generation capacity, or 42 000 MW, is powered by coal. That is a starkly uneven figure, in comparison with other energy sources. Nevertheless, nuclear is gaining prominence around the world, and stands at approximately 10% of the aggregate power generation, with over 400 Gigawatts of capacity. As South Africa seems to struggle with vigorous momentum towards building capacity in this energy source, need arises to make a perfect case for the indispensable part that nuclear energy has to play for energy security, industrial growth and diversity.  This first, of a three-part series, therefore, outlines the elementary issues associated with nuclear power, such as; cost, advantages and disadvantages. The next issue will provide detail on S.A’s policy direction regarding nuclear energy, with suggestions on how the country can utilize its past successes in order to add much needed new power online. 


Cost and choice of scale

Large nuclear power plants are the standard model used in nuclear energy technology. They vary in size from 1000 MW to 4000 MW. On the other hand, there is a smaller alternative, known as the Small Modular Reactor (SMR). SMR’s are built to produce between 100 MW- 600MW of electricity. The choice between a large plant or an SMR depends on factors such as, affordability, location of the plant and speed with which the plant should be brought online (provide electricity). Large nuclear plants, have a higher capital expenditure requirement than their alternative (SMR’s). Huge plants can cost as much as $7000/ kW (or $7 billion for 1000 MW). The OECD Nuclear Energy Agency’s (NEA’s) 2020 capital cost estimates, of building a conventional nuclear plant ranges from $2157/ kW in South Korea to $6920/ kW in Slovakia. For China, the value was $2500/kW or only $2.5 billion per 1000 MW. The differences in cost are dependant on the country’s available skilled personnel, technology for fabrication, government’s experience in handling nuclear projects, etc. On the other hand the smaller SMR’s can be as low as $3000/ kW ($3 billion for 1000 MW). This is still about twice the cost of establishing a coal fired plant, however. Small Modular Reactors have an additional advantage in that, they provide room for expansion or scalability. This means that, after installing a 100 MW nuclear reactor, another 200 MW can be added at the same site, in the future. Additionally, since they (SMR’s) take up less space, there is location flexibility, whereby they can be installed almost anywhere. This is not the case for large plants which depend on availability of large amounts of space. Large nuclear plants also need massive amounts of water for cooling. Resultantly, they are typically established close to an ocean or sea, where water can be drawn nearby, using pipes or other applicable technologies, from the water source to the plant. This however, is not the case with SMRs as they can operate even in arid regions. The higher upfront cost of a large reactor does have an upside to it, as it translates to scale efficiencies, through the full life of the plant. In essence, it means that, by the end of its life cycle (40- 60 years), the larger plant would have produced more efficient and affordable power than the SMR. To put it another way, this also means that, nuclear plants are expensive to build but cheap to run. This is not only true when comparing the scale and efficiency of nuclear plants of different sizes, but also when comparing with other energy sources (coal, gas and oil, etc). For empirical figures on overall energy costs, over a plant’s lifetime, the U.S. EIA, in 2017, published the electricity cost per unit, of nuclear plants to be brought online in 2022, comparing them with other energy sources. The numbers were; 9.9c/kWh (advanced nuclear), 5.7-10.9c/kWh (natural gas), 12.3c/kWh (coal), 14.6c/kWh (offshore wind), 18.4c/kWh (thermal solar). It is vital to note that, the calculations include both capital expenditure for construction and operational costs. This clearly outlines that nuclear energy is cheaper. Additionally, The Canada West Foundation (an independent public policy think tank), posits that total fuel costs of a nuclear power plant in the OECD are typically one-third of those for a coal fired plant. Understanding that coal is the least expensive fossil fuel, shows that, nuclear is therefore, outstandingly cheap. 

Kevin Tutani is a political economy analyst- tutanikevin@gmail.com

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