Climate change: Drought highlights dangers for electricity

[no1novice]

Climate change: Drought highlights dangers for electricity supplies

By Matt McGrath
Environment correspondent

Published

6 hours ago

Related Topics

Europe heatwaves

Spain droughtImage source, Getty Images
Image caption,

Drought in Spain is exposing villages that were submerged by the building of dams and reservoirs

The ongoing drought in the UK and Europe is putting electricity generation under pressure, say experts.

Electricity from hydropower - which uses water to generate power - has dropped by 20% overall.

And nuclear facilities, which are cooled using river water, have been restricted.

There are fears that the shortfalls are a taste of what will happen in the coming winter.

In the UK, high temperatures are hitting energy output from fossil, nuclear and solar sources.

That is because the technology in power plants and solar panels work much less well in high temperatures.

The prolonged dry spell is putting further pressure on energy supplies as Europe scrambles for alternative sources after the Russian invasion of Ukraine.



Hydropower is an important source of energy for Europe, but the lack of water in rivers and reservoirs is now significantly reducing the ability of facilities to produce electricity.

Italy gets around 1/5 of its power from hydro, but that's fallen by around 40% in the past 12 months.
energy graphic



It's a similar story in Spain, where the amount of electricity generated is down 44%, according to data from energy researchers Rystad Energy.

"Hydropower can be quite volatile, but 40% is absolutely extreme," says Fabian Rønningen, a power analyst with Rystad.

The figures are not just down in one part of Europe, he explains, but all the big hydropower-producing countries are making less now.

"It's really a big impact,," he adds.
Italy droughtImage source, Getty Images
Image caption,


Italy has been hit hard by drought limiting energy from hydroelectricity by 40%

Norway is also experiencing challenges with hydro-electricity. It warned that it may not be able to continue to export energy to countries like the UK unless its reservoirs were refilled.

Some in the hydro industry say that lack of investment in modernisation and in transmission lines are also causing problems.

"We are going to face a problem this winter. And that should be a wake-up call to have more investment in the infrastructure for the next few years," says Eddie Rich from the International Hydropower Association.

The exceptionally hot weather is also hitting nuclear power production, especially in France. Around half of the 56 reactors in the fleet are offline, with several affected by a systemic issue with corrosion.

Those reactors that are working are often cooled with water from rivers that are now running low, while temperatures are running high.

"Once the water in the rivers is very low and very hot, basically you have to stop cooling down nuclear power plants. That's because the water that's released is dangerous for fish and other species in the rivers," said Prof Sonia Seneviratne, from ETH Zurich.

The French government is now allowing some facilities to release very warm water back into the rivers, as a temporary measure.

It underlines the stresses the heat is putting on energy production. France is now making up the shortfall in electricity by importing from the UK among others.

Analysts say this is putting additional pressure on the UK system - at a time when the very warm weather is hitting production from gas and nuclear facilities.

It's more difficult to cool the plants in the warmer weather, explains Kathryn Porter, an energy consultant with Watt-Logic.

"Solar panels also experience quite a significant drop off above 25C. Everything just works less well when it's hot," she adds.
solar UKImage source, Getty Images
Image caption,

Power output from solar farms in the UK will be hit at temperatures soar

The stresses in the UK system were evident this week when the National Grid triggered a capacity market notice, a technical step indicating that the safe margins for operating the grid were reduced.

Countries, including the UK and France, rely on each other's electricity markets.

"If both French and UK systems are in stress at the same time, then nobody really knows what will happen," Ms Porter says.

She said it is a foretaste of what may happen in winter and warns that there may well be restrictions on energy use for large consumers.

Follow Matt on Twitter @mattmcgrathbbc.

www.bbc.co.uk/news/science-environment-62524551

[no1novice]

The science of drought explained in pictures

By Helen Briggs
Environment correspondent

Published

23 hours ago

Related Topics

Climate change

Parched cricket fieldImage source, Getty Images

From all the pictures of parched fields, dusty soil and dried-up reservoirs, it might appear obvious there's a drought.

But from a scientific point of view, it's more complicated than that.

There's no one definition of drought - it's different depending on whether you look at weather, agriculture or water flow in rivers and streams.

And when it comes to declaring an "official" drought, government agencies look at how the long dry spell is affecting food production, water supplies and the environment.

That includes how much rivers and streams are shrinking, which puts wildlife and water supplies at risk. They also look at threats to crops and livestock if fields are turned into dust bowls.
How water supply is affected

One big indicator for drought is hydrology - the flow of water through rivers and the state of the water stored underground in permeable rocks beneath the soil.
Baitings Reservoir in West Yorkshire




These are crucial for supplying the drinking water that reaches our taps.

Rivers are running at exceptionally low levels in much of southern England and Wales, including the River Yscir, Colne and Wye. There are reports of streams drying up and rivers shifting downstream.
River Thames at KembleImage source, Getty Images
Image caption,


The source of the River Thames has dried-up and moved 5 miles downstream

The amount of water stored in aquifers - the layer of spongy rock that soaks up water - is below normal for this time of the year.

Reservoirs are also running empty. At the end of July reservoirs were at their lowest levels in England and Wales since records began in 1990, according to the UK Centre for Ecology and Hydrology.
Depleted reservoirImage source, Getty Images
Image caption,
Reservoir levels are running low as water use soars during the hot summer



A north-south divide

But it should be noted that there's something of a north-south divide. Because of the UK's geological make-up and the influence of weather patterns, some parts of northern England and Scotland are escaping the worst of the parched conditions.

Rivers in the north are generally at higher levels and also respond much more quickly when rain falls.

That said, the drought in much of southern England and parts of Wales is likely to persist for some time. Even if it does rain, it'll take a long time for river levels to fill up enough to return to normal flows.
How drought affects food and wildlife

Experts warn the extreme weather will likely lead to smaller harvests, which will make the food we buy in the supermarkets even more expensive.
Field of damaged maizeImage source, Getty Images
Image caption,

Farmers say the soil is too dry for seeds to germinate

Scientists will be monitoring the impacts of the drought on wildlife. As water courses dry up or run low, habitats for fish and invertebrates start to shrink, with knock-on effects for animals higher up the food chain.

And pollutants in rivers become more concentrated, amplifying their impact on wildlife.
How climate is linked to drought

Experts will also be looking at the wider question of the links between heatwaves, drought and climate change.

The UK has experienced regular periods of drought in the past, including the last official drought in 2018-19. And to a certain extent, drought is normal and part of natural weather cycles across the world.

But dry conditions are also expected to become more frequent and intense as Earth moves beyond the 1.2°C of climate change we have seen to date.

The ten warmest years on record in the UK have occurred in the 21st century, with data stretching back to 1884.
Top 10 hottest UK days on record



Climate scientists say that the UK's extreme heat in July would have been "almost impossible" without human-induced climate change.

July was the driest in England since 1935, with many areas seeing far less rainfall than average.
Weekly rainfall

The latest set of simulations for the UK project hotter and drier summers, plus warmer and wetter winters, with larger changes in summer compared to winter rainfall.

That means water companies and farmers will have to plan how to harvest and store rain in winter to address shortages in the summer.

Follow Helen on Twitter @hbriggs.

[kittylady]

But climate change is a lie, right?

[no1novice]

Yeah yeah - *distracted due to planting wine vines*

[lindsaywhit]

Kinda terrifying, isn't it?