Some of the most reliable grids in the world are those with a high share of solar and wind. Photo: © Werner Rebel /

Renewables are planable

There is no need for fossil fuels or nuclear power to stabilise our power system. Large power plants actually increase uncertainty, since the effects are so great when they fail to deliver.

For the past few years solar and wind power have offered the cheapest new electricity almost everywhere in the world, according to global surveys by knowledge brokers such as Bloomberg New Energy Finance.1 In some countries the total cost of new solar and wind power is lower than the cost of continuing to operate existing nuclear reactors and coal-fired plants, as demonstrated in an analysis by Lazard a couple of years ago2.

This has wonderful consequences for the ambitions to reduce greenhouse gas emissions and air pollution globally. Reductions in the use of fossil fuels may happen as a result not only of actions by idealists but also through the actions and investments of those who seek economic profits. The IEA now expects most of the new electricity production in the world until 2025 to come from renewable energy3.

But some groups will lose money and power as a consequence: the owners of oil, gas, uranium and coal resources, and the power plants that use these sources, as well as the largely taxpayer-financed nuclear technology scientists who fear that the demise of nuclear energy will rob them of an income.

One of the countries with the most to lose is Russia. Unlike the countries in the Middle East that are developing the world’s cheapest solar electricity and combining these investments into industrial strategies for the future, Russia has no alternative. Russia’s trade balance and about half of its state budget depend on exporting oil, fossil gas, coal and nuclear fuel.

Those who delay renewable development claim that you need something that they call “baseload”, “dispatchable”, “stable”, or “planable” power, which usually means nuclear or fossil-fuelled generation.

But what we need instead is an ensemble of generating facilities that use different energy sources which, together with flexible demand, can keep the electricity grid in balance. All requirements can be economically met with renewable energy.
When solar and wind increase production they replace fossil fuels, resulting in lower demand for fuels and lower fuel prices. This has the consequence that electricity generation becomes cheaper even when the wind is not blowing or the sun is not shining. Fossil fuels are easily stored, even gas can be stored in storage facilities in Europe. In Scandinavia, energy from wind turbines is stored in water reservoirs in the hydropower system, increasing supply and lowering prices even when the new renewable sources produce less.

Short-term balancing does not need rotating energy from large synchronous generators. It can be achieved at lower cost with batteries and power electronic installations, as demonstrated in South Australia4, and explained by NREL5.

These stabilising installations are required because of fluctuations in the supply of power when large nuclear reactors or fossil-fuel plants shut down for unpredicted technical reasons. This may also happen when large power lines fail for technical reasons.

Some of the most reliable grids in the world are those with a high share of solar and wind. The reason is that these sources are predictable, and technical failures do not disturb the grid to the same extent as failures in nuclear and large coal plants.

Those who suggest that nuclear is “stable”, “planable” or “dispatchable” should be reminded of the real performance around the world. Numerous, sudden and unpredicted shutdowns of nuclear reactors have occurred in Sweden in recent years. The Ringhals 4 reactor in Sweden was supposed to restart following routine maintenance in August 2022, but following several postponements it will not restart until March 20236 at the earliest. In France, unintended problems reduced nuclear generation by 80 TWh during 20227, turning France from the world’s largest net exporter of electricity into a net importer and contributing to record-high prices in Europe during 2022.

Germany managed to compensate for phasing out its own nuclear reactors by generating more renewable electricity and decreasing consumption. Its fossil-based electricity generation increased by 3 TWh and the export of electricity by 6 TWh8. Only Sweden exported more electricity than Germany during 2022.

Tomas Kåberger

1 wall


In this issue