Unless you work at a coal, gas, or nuclear plant, you may not think about water when you think about electricity (certainly at a household level; they don’t mix). But water plays an important part in cooling many power plants, and many power plants also depend on a nearby water source to create steam that drives turbines. So the availability of water for power production is a serious consideration. Not enough water? That power plant could have to shut down. If the water isn’t chilly enough to cool the plant? Same problem.

In a paper published in Nature Energy this week, a group of researchers from the Netherlands estimated how water availability would affect coal, gas, and nuclear plants in the European Union out to 2030. The researchers took into account a changing climate that will likely make water reserves scarcer and warmer, but they also accounted for progressive renewable energy policies in EU member countries, which are already prompting some thermoelectric plants to retire in favor of wind and solar (which need negligible amounts of water to operate). The researchers also counted new coal, gas, and nuclear plants that are in the planning or construction stages and will likely come online before 2030.

The model tracked the “water footprints” of 1,326 thermoelectric power plants in Europe (that is, the amount of water they need to operate), as well as 818 water basins from which those plants draw water. The researchers found that by 2030, plants along 54 water basins could experience reduced power availability because of lack of water for cooling or steam production, up from 47 in 2014. If the EU were to experience summer droughts like those that occurred in 2003 or 2006, power shortages would follow, the paper noted.

Although seven additional basins experiencing water shortages out of 818 may not seem like a lot, it's compounding problems that already exist. Thermoelectric power plants already experience some amount of stress in regions along the Mediterranean coast, namely in Portugal, Spain, Italy, Greece, and Bulgaria. The researchers also note that they only counted thermoelectric plants that were 100MW or larger and can’t be absolutely certain of how energy markets will play out 12 years into the future. “While future capacity is uncertain, this does indicate that our results should be viewed as a lower limit of vulnerability, with possible future impacts being greater,” they wrote.

It seems that, despite the planned retirement of EU thermoelectric plants in favor of wind and solar, cool water scarcity will still be a factor in a warming world. By 2030, areas that see increased probability of experiencing shortages spread to France, Germany, and Poland.

The paper reports that there are a few things we can do to prevent these kinds of water/power shortages, but all of them cost money. On the Mediterranean coast, retrofitting plants for seawater cooling could be cost-effective. Fitting power plants for dry air cooling with a condenser or a secondary air cooling method could work in other areas, although it’s generally far more expensive than its more traditional counterparts. Alternatively, plants could retire early after two-thirds of their expected lifetime. Another option would be for policy makers and investors to scrap currently planned and under-construction thermoelectric plants and replace that capacity with renewable energy instead.

In studying the possible adaptations that grid planners could undertake, early retirement of thermoelectric plants seemed to be the most effective at reducing water use. But it’s not quite so cut and dry as that, because it depends on whether and how you replace that capacity with something else. The researchers admit that a lot of prime candidates for climate-mitigating courses of action also use a lot of water. “Biofuel production and carbon capture and storage sharply increase the water demands as compared with their more carbon-intensive counterparts,” the paper notes.

Instead, they argue, what’s needed is a closer eye on river basin management to adapt power plants to regional demands. This isn’t always as easy as it sounds, the researchers explain, because energy policy and water policy have evolved separately from each other in many cases, especially when water resources are shared by many countries. Water basins often intersect administrative and even national boundaries, making cohesive energy and water management difficult, since water policy is often governed by political rather than hydrological boundaries.

Barring cooperation and intelligent management, the EU puts itself at risk to be vulnerable the next time a drought rolls around.

Nature Energy, 2017. DOI: 10.1038/nenergy.2017.114 (About DOIs).