Climate change live ticker: What we need hydrogen for

The potential of safe nuclear power: It is always discussed whether nuclear power should be part of the energy transition or not. In this way, electricity can be produced in a CO2-neutral manner. However, nuclear waste is generated and overheating would be extremely harmful to people and nature. But what if there is a safe nuclear power plant that produces less nuclear waste? That should so-called Thorium liquid salt reactors Offer. China recently put hope in this technology. The journal Nature reported in September that the country is testing such a reactor. Initially, however, the reactor is only designed for an output of two megawatts. That would be enough to supply around 1,000 households with electricity. If the experiment succeeds, China plans to build a reactor capable of producing 373 megawatts of electricity by 2030. This makes it the first country to test a thorium liquid-salt reactor with the aim of commercializing the technology.

Thorium is a radioactive metal like uranium, but is far more common. That’s why it’s cheaper. It can be found as a by-product of rare earths and is mainly found in Norway, India and China. In addition, thorium reactors produce less nuclear waste. The rubbish that is created anyway decomposes faster. The material itself therefore offers a number of advantages over conventional uranium nuclear power plants. Another is the construction of the power plants. Thorium is dissolved in liquid salt in the reactors. The molten salt is both fuel and coolant. Nuclear fission takes place in the liquid. The resulting heat heats separately stored water. Its steam, in turn, drives a turbine, which enables a generator to produce electricity. In addition, the heat from nuclear fission ensures that the liquid is kept liquid at at least 500 degrees Celsius. If the system should now overheat, the volume of the salt increases. This cools it down and makes it firmer. That makes Meltdowns like Chernobyl, unlikely. In addition, because water and fissile material are separated from one another, no explosive hydrogen can be produced if the facility overheats. So are too Gas explosions like at Fukushimaunlikely.

In theory, thorium liquid salt reactors are therefore safe and CO2-neutral power generators. In practice, however, they still have to be tested – and that takes time. Even under optimal conditions, according to the En-ROADS climate simulator, it would take decades to catch on. If the technology were to hit the market before 2030, it would take another 10 years to spread far enough to displace coal. If the reactors could also produce electricity twice as cheaply as coal, they could reduce global warming by 0.2 degrees Celsius. A CO2 price of 15 to 20 euros would have about the same effect. So safe nuclear power offers a lot of potential, but it will probably come too late.