EnBW loses hydropower output due to drought

The observation is scientifically backed by the Climate Expert Council of Baden-Württemberg. The panel had previously warned of increasing water scarcity in the state as a result of climate change. The council bases its statements on evaluations by several research institutes in the state.

Why hydropower declines during drought

For electricity generation from hydropower, this means that some of what has so far been reliable generation could fail more frequently in the future. Hydropower plants were long considered a plannable, baseload-capable energy source, as they can deliver electricity regardless of the time of day or weather. When the flow rate drops, the feed-in into the grid also drops – without another plant being able to compensate for this gap in the short term.

EnBW operates several hydroelectric power plants in Baden-Württemberg, which together make a notable contribution to the company's overall electricity generation. These include plants on the upper and middle Neckar, on the Enz and Nagold, as well as the Rheinkraftwerk Iffezheim on the German-French border. Even though the share of hydropower in the group's energy mix is limited, it is considered an important component of climate-friendly generation.

Implications for the electricity supply

According to the current assessment, the consequences for electricity customers are limited, as missing hydropower volumes can be compensated for by other generation plants and the electricity market. Observers point out, however, that longer dry spells could put pressure on supply security overall if several forms of generation are weak at the same time.

The Climate Expert Council sees Baden-Württemberg in a phase of accelerated climate change and expects more frequent heat and drought periods. The council therefore recommends planning water uses – including for energy generation – more proactively and expanding storage capacities. EnBW itself had recently announced that it would continue to push ahead with the expansion of renewable energies.

Recommendations from the Climate Council

Observers see the current figures as a warning signal for the energy transition as a whole. If classic renewable sources such as hydropower suffer from climate impacts, supply must rely more heavily on diversity and flexibility. This includes wind and solar energy as well as grid storage and a powerful electricity grid that can balance generation peaks and shortfalls.

At the power plant sites themselves, operations are meanwhile continuing largely as normal. The turbines are adjusted to the reduced water flow and switched off on an hourly basis when the minimum flow for ecology and shipping must not be undercut. EnBW also refers to regulatory requirements that govern the operation of the plants during low water.