It is estimated that by 2040 global use of electricity will be more than double what it is today – and some experts say it will be triple. Not only is the world’s population growing, but we are being pushed to switch to electric cars. There are over 1.4 trillion cars in the world, with 700 million in Europe and the US alone. Where will all of this extra electric energy to charge those cars come from? At the moment most of our electricity is still produced from fossil fuels which create vast amounts of air and water pollution. In addition, they are a major cause of other environmental hazards like acid rain and the human element of climate change. It is not only the operation of the fossil fuel power plants that produces the pollution, but also the mining, drilling and processing of the coal, oil and gas. It is unrealistic to think that we can completely replace fossil fuels in the short term, but it is very possible to reduce their impact by increasing our reliance on clean sources of energy - wind, solar and nuclear. Let’s look at these alternatives to get an idea of what is the best mix for providing reliable clean energy. 

In terms of efficiency, wind turbines convert about 20% of wind energy into power, and solar panels get about the same percentage from sunlight. Nuclear power offers high energy density, which means that a small amount of nuclear fuel produces a large amount of electricity. Longevity is another important factor. The giant wind turbines have a lifespan of about 20 years, while solar panels can last up to 25 years before they need to be replaced. Older nuclear plants have remained in operation for about 60 years, and the newer ones are designed keep working even longer. Another thing to consider is the environmental impact on land use. Large scale solar and wind power installations require a great amount of land. Some of this is mitigated by installing solar panels on existing structures, and building wind turbines in the sea. On the other hand, a nuclear power plant uses relatively little land.

 

Each type of clean energy has its own pros and cons, but the most important challenge faced by both wind and solar is the problem of intermittency. Solar energy is obviously dependent on sunlight, making it unsuitable for regions with limited sun exposure. Even in sunny locations it is not possible for solar energy to be produced continually due to cloudy weather, seasonal variations, and of course the lack of sun for the entire night. Wind energy is an unpredictable source because the availability and strength of the winds can vary significantly. The intermittent nature of these two sources makes them unsuitable for creating a constant reliable flow of electricity on the grid. One solution is to store excess energy when the wind or solar is strong, so that it can be available when needed. Storage of energy in batteries is useful on a small scale for solar power in homes and businesses - particularly in sunny places like Ibiza. But battery technology is not yet feasible for large power plants that supply the electricity grid.

 

The obvious solution to the problem is to back up wind or solar with a consistent source of power that will ensure a continuous and reliable flow of electricity. This is what is being done in most countries, but the majority of that power still comes from polluting fossil fuels. Nuclear would seem to be a better answer as it is a clean efficient source that can run 24/7, providing the stable power supply which is essential for a modern society.  However, the replacement of coal, oil and gas with nuclear power ran into a roadblock back in 1986, as a result of the accident at Chernobyl in the Soviet Union. That was caused by a poorly designed old reactor which was mismanaged. It tragically blew up, killing 31 workers and spreading radiation to a wide area around the plant. At the time it was thought that many more people might die from the radiation, but over the past 37 years only a small number of deaths can be directly attributed to the disaster. However, it is possible that many more may have suffered from the radiation. This accident caused understandable fear in the public, which was enough for many governments in the West to scale back or stop their nuclear programs.

Perhaps it is time for those countries to reconsider whether modern nuclear energy might be the cleanest and best way to fill the inevitable gaps in the grid caused by wind and solar. The benefits of nuclear over fossil fuels are clear, but there are also realistic concerns about safety and the disposal of nuclear waste. The nuclear industry has learned valuable lessons from the accident at Chernobyl and one at Fukushima Japan in 2011. As noted above, Chernobyl was badly designed and poorly managed. Fukushima was a newer plant, but it was victimized by a massive earthquake which immediately caused a tsunami to hit the plant. Advanced reactor designs make modern nuclear plants much safer than their predecessors. They incorporate passive safety systems that automatically shut down the reactor in the event of an emergency. An excellent example of modern nuclear energy safety is France, which for many years has gotten 70% of its electricity from nuclear plants and has never had a serious accident.

Another challenge for nuclear power is the disposal of the radioactive waste that it generates. The spent nuclear fuel needs to be securely stored for thousands of years to prevent any environmental or health risks. The newest plants have technological advancements that extract additional energy from spent fuel, thus making it less dangerous. Storage has been solved by the development of deep geological repositories which can safely hold the waste in impenetrable containers.

Today there are over 400 nuclear power plants operating in the world. However, until recently there had not been any new ones built in Europe for 15 years. That drought ended this year when Finland opened a state of the art reactor that will give them energy independence for many decades. France plans to build at least six new reactors, and possibly as many as 14. The UK wants to reduce its reliance on oil and gas by building eight new nuclear reactors, reversing what it describes as “decades of underinvestment”. Yet other countries in Western Europe are still frozen by the fears that started with Chernobyl. A good example is here in Spain where we have seven nuclear reactors providing about 20% of the country’s electricity, but they are all scheduled to be retired by 2035. Why are some countries giving up on this clean and reliable source of electricity? Does it make sense to keep using fossil fuels to augment wind and solar, or is expanded nuclear energy a better alternative?