“You can quite literally feel the power here,” says Hilde Bakken, executive vice president for hydropower at Norwegian energy company Statkraft, Europe’s largest producer of renewables.
She is standing next to one of the large yellow and orange generators of the Kvilldal hydroelectric power plant. Deep inside the mountains of western Norway, a row of UFO-like machines makes enough electricity to cover all of Brussels’ electricity use — and then some. Bakken’s job is to manage 17.7GW of installed capacity, which generated 62.4TWh of electricity in 2020.
Kvilldal is one of Norway’s 1,100-plus hydroelectric plants. Hydropower is gaining importance in the European power system, as its dispatchable power production — which can be switched on and off as electricity demand rises and falls — is a perfect fit with the growth in new intermittent wind and solar power in Europe, with natural storage making it possible to shift production over seasons as well.
“The power production here at Kvilldal can be turned on in five minutes. It takes two years and nine months to fill the reservoir, and we can produce all of the power stored in eight months,” Bakken says over the loud hum from the Francis turbines powering the generators. “So, it complements power production from wind turbines and solar plants nicely. Statkraft alone has 40TWh of dispatchable production capacity in Europe, ready on a few minutes’ notice to balance intermittent production that can’t as easily be turned on or off.”
The power production here at Kvilldal can be turned on in five minutes
How much is 40TWh of dispatchable production, you ask?
“That’s about 400 million Tesla car batteries, charged and ready to be turned on,” Bakken says. “Imagine a line of fully charged Teslas stretching 60 times around the equator. It is a lot.”
The flexibility challenge
The Renewable Energy Directive is a key element in the upcoming Fit-for-55 package, in which the Commission will revise its climate and energy legislation. The directive provides important parts of the framework for increased development of renewables required to bring Europe toward zero emissions. All analyzed options in the Commission’s “Impact Assessment” conclude that the renewables share needs to increase to between 32 percent and 40.4 percent. This calls for more renewable electricity to come online in Europe, including 10 per cent more hydropower and 40 per cent more pumped-storage hydropower capacity — and all of it needs to be built in nine years.
The increase in intermittent power creates a challenge: how to keep enough power in the grid when intermittent renewables do not produce electricity?
“It’s a big challenge,” says Bakken, “and it’s even more complex than it might appear, because flexibility needs vary a lot depending on where you are and the time of year.
“Some places it’s all about sudden, big variations between hours, minutes or even seconds when wind and sunshine come and go during a summer day in Spain. Other places, you need to handle weeks or months of low wind or solar production, such as in Germany in winter.
“There are many answers to this challenge, including batteries, hydrogen use, interconnectors and more flexibility on the supply side.”
“Still, it’s very hard to beat existing hydropower from a cost perspective, but also from a holistic sustainability perspective taking into consideration climate and societal benefit.”
Last week, the International Energy Agency released its “Hydropower special market report”, a large-scale analysis of hydropower’s global future. “Hydropower is the forgotten giant of clean electricity, and it needs to be put squarely back on the energy and climate agenda if countries are serious about meeting their net-zero goals,” said Fatih Birol, director of the IEA, at the launch. Bakken agrees, adding that the IEA report is a timely reminder of the key role of hydropower in combating climate change and providing flexibility.
Hydropower is the forgotten giant of clean electricity
“Putting hydropower back on the agenda also means ensuring good framework conditions for both construction of new capacity, as well as for reinvestments into modernization of existing plants,” she adds.
The report identifies seven priority areas for governments to accelerate hydropower growth. These areas include recognizing the critical role of hydropower for electricity security and maximizing the flexibility capacities of existing hydropower plants. The report states that: “With its ability to supply large amounts of low-carbon electricity on demand, hydropower is a key asset for building secure and clean electricity systems.”
Bakken adds: “The renewable flexibility from hydropower helps stabilize the power system and brings down balancing costs. Thus, hydropower contributes to security of supply both in the short and longer term. So, with hydropower as part of the European renewable mix, we get a more stable power supply, as well as more stable power prices.”
Hydropower: Enabling a green future in Europe
Hydropower contributed a 13 percent share of total electricity generated in Europe in 2020, up 4 percent from 2019 — more renewable electricity than all other renewable sources combined, according to the IEA. That figure could understate its long-term importance in the European power system however, as hydropower’s flexibility enables a high share of intermittent power in the power mix.
“We usually say that 1TWh of flexible hydropower enables the construction of at least 3.5TWh of intermittent wind or solar. We know that the intermittent share of Europe’s power mix will increase significantly going forward, which means that hydropower’s role as flexibility provider that supports other renewable growth is becoming ever more important. It also means that the financial case for investing in hydropower for the long haul is positive,” says Bakken.
Which is why she spends 500,000 euro every day on refurbishing Statkraft’s hydropower plants. Hydropower plants in Europe are, on average, 45 years old. In IEA’s investment outlook for Europe towards 2030, 90 percent of hydropower investments will go into the modernization of existing facilities. Back at Kvilldal, they are ready to celebrate the plant’s 40th birthday.
“Its 40th ‘birthday present’ has been a refurbishment of its generators and tunnels. It’s been a 10-year project, and we are investing about 80 million euro in Kvilldal and nearby plants,” Bakken says.
“But actually, 40 years is not very old at all for hydropower. Our power plant Øvre Leirfoss in Trondheim in Norway started production in 1901 and it’s still going strong. So, for us, it’s all about the future. With proper maintenance, and as long as rain or snow exist, these plants can produce power essentially indefinitely. They are built to last.”
These plants can produce power essentially indefinitely. They are built to last.
Climate mitigation plus climate adaptation
Over the life cycle of the power plant, hydropower offers some of the lowest greenhouse gas emissions per unit of energy generated. Hydropower is not only climate friendly, but also plays a key role in climate adaptation and flood reduction. A changing climate means higher likelihood for extreme weather events, like sudden heavy rainfall or heatwaves melting snow in the mountains, causing floods. Hydroelectric reservoirs can play an important role in reducing such risks.
“These floods can often be predicted before they happen. Active reservoir level management can reduce flood damage downriver very significantly,” says Bakken.
Even as most investments go into modernization, there is still potential for more hydropower to be built. IEA states that globally, around half of hydropower’s economically-viable potential is untapped. The potential is particularly high in emerging and developing economies, reaching almost 60 percent. New construction of hydropower is also important for attracting new skilled workers to the energy sector.
Failing to build enough new sustainable hydropower capacity could even put climate targets at risk, suggests the IEA…