In an age of energy-hungry data centers, countries around the world have raced to install solar panels and wind turbines. One unexpected bottleneck: aging electricity grids that can’t handle the power.
In the U.S., decades-old transmission lines have been blamed for hindering the rollout of new energy projects. In Europe, a sweeping blackout in Spain in April highlighted how big power swings can overwhelm the system. Meanwhile, China’s rollout of ultrahigh-voltage transmission lines is now seen as giving it an edge in the artificial-intelligence race.
Global investment in electricity generation has surged almost 70% over the past decade to $1 trillion a year, but annual grid spending has only risen to $400 billion, according to the International Energy Agency.
The U.K. offers a cautionary tale. Britain built a vast network of wind and solar farms and generates a higher proportion of its power from renewables than most places in the world. But it didn’t build the transmission lines needed to move all that clean energy around.
Britain’s grid hasn’t undergone a major upgrade since the 1960s, when the rising popularity of refrigerators and washing machines turbocharged demand for electricity. The country is now embarking on an expensive building boom, sparking outrage at unsightly transmission towers and the potential harm to bats, dormice and other local wildlife.
At stake is Britain’s ability to capitalize on the AI boom, and secure the jobs and investment that come with it, as well as to lower household electricity bills.
National Grid is investing the equivalent of about $40 billion to upgrade the U.K.’s power networks over the next five years in a project dubbed “The Great Grid Upgrade.”
Grid upgrades and associated costs add to what are already some of the world’s most expensive electricity bills. The average-size British household paid almost $1,500 for electricity last year, more than double the bill in 2008, government data show. That’s close to the $1,700 that American households pay each year for consuming three times as much electricity.
Outdated infrastructure has created massive distortions in the energy market. Wind farms off the coast of Scotland are far from customers in the populated south, and leaving them constantly on risks frying the grid. The U.K. paid power generators $2.3 billion in the year to March to not produce electricity, a bill that is set to rise in coming years.
The lack of grid capacity means there is a green-energy bottleneck. Want to build a new wind farm or battery storage unit? Get in line. It takes five to 10 years to get a grid hookup.
When Lindsay McGrow first started helping wind farms in Scotland connect to the grid two decades ago, it would typically take a little over two years. Today’s longer wait may be fine for large, offshore wind farms that can take five to six years to design and build, “but for a battery site, people think it’s crazy,” the consultant said.
To speed things up, the U.K. recently scrapped its first-come, first-served system for grid hookups. Grid operators are now fast-tracking connections for projects that they see as ready-to-go and aligned with national targets, and kicking other projects off the wait list.
The roots of the grid problems lie in the 19th-century build-out of Britain’s early electricity supply.
Historically, most of the U.K.’s electricity came from coal-fired power stations in the center of the country, which transmitted out across the island. Britain shut its last coal-fired power station last year, some 142 years after opening the world’s first.
The transition to renewable energy has upended how Britain gets its power.
Today, wind is the primary source of electricity generation in the U.K., contributing roughly a third of the country’s total supply. But a lot of wind farms are in Scotland, meaning the region generates far more power than it requires and needs to transmit some south, where most of the demand is. The current infrastructure isn’t sufficient to transport all that power.
“If you’ve just built a shiny new wind farm in the north of Scotland and we don’t have a network that extends up that far, no amount of technology can help you with that. You’ve got to build a new line,” said Steve Smith, National Grid’s chief strategy and regulation officer.
Another problem: The output from new solar panels and wind turbines depends on the weather, which doesn’t always align with demand.
In the past, the grid operator could coordinate with coal-fired power plants to increase output when it knew Britons would return home from work and start turning on lights and TVs. But the wind doesn’t take instructions on when to blow.
A fully modernized grid is years away. Building a new transmission line can take up to a decade, with most of that time spent consulting local communities and securing various approvals. National Grid would like to cut that time in half, but that would require changes in government policies, Smith said.
New transmission towers, known locally as pylons, aren’t always welcome. Objections from local residents and nature conservation organizations have been a major hurdle to speeding up grid upgrades.
Years of consultations on National Grid’s plan to upgrade a 112-mile power line in the east of England generated more than 20,000 responses.
Suffolk County Council demanded information about the impact on hedgerows, which are home to bats and dormice. Multiple responses raised concerns about the new equipment’s noisy hum. Another called for an existing overhead line to be removed because it runs close to the cottage featured in John Constable’s 1821 painting “The Hay Wain.”
To assuage wildlife concerns, National Grid in 2020 built a bespoke bat barn during the construction of a new overhead line. Last year, it installed an acoustic barrier to shield bats from noise while replacing underground cables.
