According to British energy research company Aurora Energy Research, the UK electricity transmission grid is unequipped to accommodate the increased influx of renewable generation capacity, creating a ‘key stumbling block’ in the country’s race to net zero.
This is according to Aurora’s Down To The Wire: The Role Of Networks In Delivering The Energy Transition, a strategic insights report released to Aurora Energy Research subscribers.
Closing the curtailment gap
The report finds that the UK’s electricity transmission system has not expanded at the same pace as its renewable generation portfolio, necessitating curtailment to fill the gap between generation and grid capacity, so as to avoid grid malfunction.
Closing this gap, states Aurora, will be crucial for the UK’s net zero pathway; expanding renewable capacity alone will not suffice.
Their studies show that, if Britain were to install the needed 40GW of offshore wind power without adequate transmission system upgrades, power sector emissions from now to 2050 would surpass the total required to reach net zero by 55%.
By contrast, delivering all of the grid upgrades currently planned by energy market regulator Ofgem and TSO National Grid would cause power sector emissions in 2023-2050 to fall 9% below the same level required.
Ashutosh Padelkar, GB research associate at Aurora Energy Research, commented on the UK net zero modelling: “Delivering the grid upgrades planned by Ofgem and National Grid would require nearly 10,000km of additional transmission lines: a very tall order.
“Long-duration energy storage (LDES) technologies could provide a useful complementary solution to rising curtailment alongside grid expansion, but the lack of a route to market for these technologies is a barrier to investment.”
Costs will even out
Within their report, Aurora emphasises that costs should not deter action to expand the grid.
Delaying grid buildout, they state, would not reduce costs for consumers. And failing to deliver all the grid upgrades currently planned by Ofgem and National Grid would not cost any less than deploying the required infrastructure in time, their modelling shows.
The buildout envisaged by Ofgem and National Grid would cost an additional £49 billion ($62.7 billion) compared to Aurora’s inadequate upgrades’ scenario, but the increase would be offset by lower grid management costs due to reduced curtailment.
Total power system costs, ultimately borne by consumers, under both scenarios are roughly equal, whereas the “upgrades delivered” scenario costs just under 1% less.
A not-so-straightforward conundrum
However, Aurora adds how deploying the necessary grid infrastructure to reach net zero will not be straightforward.
Specifically, planned transmission upgrades in the UK would cause cumulative steel demand for the transmission system to rise by 450% between 2025 and 2035.
Britain will also face strong competition globally to meet this demand—Aurora forecasts Germany and Spain each to deploy more than three times as much additional grid infrastructure by 2050 as Britain, for example, likely straining global supply chains.
Expansion projects in Britain also face the challenge of securing planning permission, with projects typically taking 6-8 years to obtain all of the required permits to begin construction. Growing backlash from local residents poses a key obstacle to streamlining the process.
Richard Howard, global research director for Aurora Energy Research, commented: “Great Britain has made great strides in building wind and solar projects over the past decade and has ambitious targets to deploy more renewable power generation.
“This is necessary but not sufficient to deliver our net zero targets: we also need to accelerate investment in grid capacity to link these projects to our cities and towns. Britain already faces a growing problem of having to turn off significant amounts of renewable power when the grid is constrained and this will increase sharply unless we deliver the required grid upgrades in time.”
Renewable power generation represents one of the UK’s “greatest successes in the race to reduce greenhouse gas emissions to net zero by 2050,” states Aurora in a release announcing the findings from their Down to the Wires report.
The country’s installed renewable power generation capacity was found to have more than tripled from 2012 to 2022, allowing renewable power plants to account for 41% of total electricity generation in 2022.