Shutting down nuclear and coal – can Germany keep the lights on?

Germany’s target of achieving greenhouse gas neutrality by 2045 has a very important sub-goal: The expansion of renewable energy capacity to provide green power for transport, heating and making hydrogen.

But running such an integrated energy system on fluctuating renewables alone will require not just more wind turbines and solar panels, but a power network that ensures the delicate balance of supply and demand at all times, while conventional capacities are shut down.

So far, the power supply in Germany remains one of the most reliable in the world. The government and grid operators are confident it will stay this way despite the challenges of electrifying the nation and experts highlight the importance of European power grid integration. But others predict that the country will soon be in need of back-up capacity.

Germany’s conventional power generation capacity is beginning to dwindle. In December 2022, the country will have over 23 gigawatts (GW) less nuclear power capacity than ten years ago.

By the end of 2022, some 13.9 GW of lignite and hard coal-fired power stations will be closed according the coal exit law. All this while the population and the economy grew and power consumption only fell slightly.

On paper, coal and nuclear capacities have been easily substituted by an unprecedented boom in renewable energy sources. The capacity of solar PV, wind and biogas installations increased from 12 GW in the year 2000 to 132 GW in 2020.

As electricity generation from these sources is less constant and its distribution in Germany itself can be described as “lopsided” with the majority of green power coming from the windy North but is needed in the industrial centres of the West and South, much depends on the ability of the country’s 35,000 km transmission grid to transport the electricity.

While some experts argue that only a fleet of gas-fired power stations could guarantee that the lights stay reliably on, others point to the existing reserves and future European interconnections as the reasons why electricity supply would remain stable.

In 2018, Germany’s influential energy industry association BDEW said that Germany would run into a “shortfall in secured capacity by 2023 at the latest”, and that the country shouldn’t rely on its neighbours to make up the difference.

Three years later and a lot closer to the nuclear phase-out, BDEW head Kerstin Andreae says: “For a secure energy supply, we also need new gas-fired power plants, as this is the only way to obtain the required controllable power.”

However, so far with fewer fossil capacities in the system and a share of almost 45 percent renewables in power consumption, the power system is still running smoothly.

“In the long term, domestic fossil fuel-based capacities will not be necessary if the integration of the European power grid and especially the interconnection and distribution of power from the vast offshore capacities in the North Sea are taken seriously,” Andreas Jahn of the Regulatory Assistance Project (RAP) told Clean Energy Wire.

“And obviously we also need further renewables expansion and the right market mechanism so that flexible capacities are added”, he said.

Nevertheless, the fear of not having enough power – even in the immediate future – and of an ensuing instability of the grid and supply is hard to shake. By the end of 2022, Germany will have switched off its last 8.1 GW of nuclear power.

Another 6.4 GW of coal capacity are scheduled for shuttering by 2023. Recent events and publications have given ammunition to those who fear a collapse of the system.

New fears after near-blackout event and auditors’ warning

On 8 January 2021, a cascading tripping of several transmission network elements, starting with a busbar coupler in the Ernestinovo substation in Croatia, led to a separation of the European transmission grid system into two areas, something that has been described as “one of the most critical near-blackout situations” since the last major blackout in Europe in 2006.

Although quickly resolved and without a link to the growing renewable capacity in Europe, the incident prompted energy industry association VIK to echo the BDEW’s 2018 warnings.

A few months after this event, Germany’s Court of Auditors, which scrutinises the government’s adherence to its measures and goals during the energy transition, said that it was not at all satisfied with the energy ministry’s monitoring and predictions of future supply security.

The auditors name the government’s plan to phase out coal and nuclear power while at the same time ramping up hydrogen production as having a “significant impact on the future security of supply.”

They also said that the measures to alleviate grid bottlenecks were not sufficient and that the ministry had failed to account for a “worst case scenario” and to specify possible solutions for it.

So, can a large industrialised society like Germany run securely and smoothly on a power system largely fed by these intermittent renewable energy sources? In the end, the question is not whether it can, but how?

By 2045, Germany wants to be climate-neutral, reaching emission reductions of 65 percent by 2030 and 88 percent by 2040. The government’s plan is to achieve this chiefly by electrifying all sectors, from transport through heating to industry, as much as possible with green power.

Having decided against the use of nuclear power and due to a lack of naturally available hydro power, intermittent generation from solar plants and wind turbines is the technology of choice – and its share in (a rising) power consumption will have to exceed 65 percent by 2030 (up from around 45% in 2020).

The energy ministry is confident that – even in the difficult years just after the nuclear phase-out– this process will not endanger the power supply of companies and households.

In a reply to parliamentarians, it wrote in March 2021: “All analyses of supply security known to the federal government and carried out in accordance with the latest scientific findings come to the conclusion that the secure supply of electricity in Germany will remain guaranteed at the current high level for the foreseeable future.

The analyses also take into account the phase-out of nuclear energy and the end of coal-fired power generation.

Source: Clean Energy Wire. Reproduced with permission.

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