Why thousands of Scottish wind turbines are turned off - and costing Britain billions of pounds every year in the process

Thousands of Scottish wind turbines are being turned off because of an insufficient network of electricity cables across Britain - costing the country billions of pounds.Only 60 per cent of Scotland's renewable electricity output is currently able to reach consumers, experts claim - given the lack of power lines linking the two countries.Because capacity is insufficient for existing wind farms, many turbines in Scotland are not able to work properly because their electricity cannot make it to the public.Gas-fired stations in England therefore have to increase their output to replace the missing power, which are given 'constraint' payments to balance the network.The total cost of balancing the grid by switching wind off and gas on hit £1.9billion last year – and could reach £8billion by 2030 without necessary grid upgrades.The cost is £44 per typical household but would reach £104 by 2031 – and could soar further unless £70billion is invested by then, the National Audit Office has said.Scotland has more than 4,700 operational wind turbines – made up of 4,228 onshore and 495 offshore – with thousands more being planned across various projects.But the cables carrying power south are already full, meaning operators cannot safely put more power into these lines – with more infrastructure urgently needed. Some Scottish wind turbines are being turned off because of insufficient cabling (file image)Grid expert Dr Iain Staffell, an associate professor in sustainable energy at Imperial College London, told the Daily Mail: 'People tend to think that Britain is paying for the mismatch between where we built wind farms and where electricity is needed.'But that was always sensible, as it is much windier in Scotland. Really, we are paying for the delay between building wind farms and upgrading the national grid to cope with them.'The main barrier to sending power from Scotland to England is simply that it has proven so difficult to build new transmission lines.'Dr Staffell said this was 'part of the broader planning paralysis' affecting projects from reservoirs to hospitals and High Speed 2 rail to the Heathrow Airport expansion.He explained that the National Energy System Operator (Neso) was having to 'route new power lines out into the sea, send them down the coast and then bring them back onto land in England and Wales', saying this is 'to avoid the curse of NIMBYs'.Dr Staffell said this was more expensive than building them on land as was done when first building the National Grid, but it 'avoids the never-ending cycle of objections and appeals'.He continued: 'Because we don't have enough grid capacity, it is often not possible to send all of the wind power being generated to customers.'Neso has to pay wind farms to reduce their output, and then pay other generators - typically gas plants in England - to replace that lost generation. 'Neso's costs get passed on to suppliers, who pass them onto consumers, so we end up paying twice for the same electricity.'Constraint payments, which were introduced in 2010, are given when the amount of wind power generated exceeds local demand - but insufficient infrastructure means they cannot be moved elsewhere in the country.Wind farms are then turned off due to the lack of transmission cables which can move power from Scotland to areas with high demand, such as southern England.Gas-fired plants near cities in England are then paid to provide the power instead while the wind energy is effectively wasted.Energy consultancy Apatura has previously described the issue as 'the bottleneck that's costing the UK £1bn a year' - given capacity is already too low for existing wind farms.It also believes around 60 per cent of Scotland's renewable electricity output can reach consumers as it stands. Upgrades are currently taking place to the Harker electrical substation near Carlisle, which moves electricity from Scottish wind farms to cities in England across the border about five miles away.But these improvements alone will not solve the issue – given that better cabling infrastructure is required to increase the amount of power which can be transferred.Dr Staffell said the Scotland-England boundary was one of various pinch points – given there are also boundaries inside Scotland which 'often get congested'.He explained: 'That means upgrading Harker alone is not going to fix the problem, because electricity from northern Scotland can often hit a bottleneck before getting to that line.'Dr Staffell cited research from the UK Energy Research Centre which 'showed that these critical links are delivering much less than their rated capacity, in part because upgrading the network involves turning off circuits - so things have to get worse before they get better'. He added that the National Audit Office has listed a series of 'missed opportunities' to approve upgrades earlier, with Harker being a 'great example of this, with hoop after hoop after hoop to jump through to get things moving'.Lawrence Slade, chief executive of the Energy Networks Association, which represents the UK's energy networks, told the Daily Mail: 'Network operators are working tirelessly to upgrade the grid, upgrades that are essential to save customers money, strengthen the country's energy security, create thousands of jobs and cement the UK's position as a clean energy leader—delivering reliable, affordable power for generations to come.'Though connections are accelerating, further reform of the planning system is required to allow network operators to go further and faster – particularly the full implementation of the current planning reform act across all regions.'Government figures show that the construction of offshore wind projects takes between two to three years, with the 2023 Winser Report finding that transmission infrastructure developments typically take between 12 to 14 years from identification of need to delivery, with planning processes responsible for the majority of this extra time.'Transmission operators, government, Ofgem and Neso are working collaboratively to reduce this time horizon to seven years.'The Government has insisted that part of the cost of managing constraints is paying for gas generation closer to demand, which has risen after the US-Iran war.Neso's actions to balance the grid are claimed to have saved consumers at least £1.2billion over the last two years – with reforms intended to avoid up to £5billion in constraint costs in 2030.Ministers are trying to cut constraint costs by reducing network delays – working to halve the time it takes to build new transmission infrastructure by reforming the planning system, supporting supply chains and minimising regulation.A Department for Energy Security and Net Zero spokesman told the Daily Mail: 'Britain's outdated grid is holding the country back.'New wind farms, solar projects and businesses are stuck waiting years for connections, keeping us reliant on global fossil fuels and driving up costs for households.'That's why we're tackling decades of historic underinvestment by reforming the connections queue, launching Great British Grid to unlock billions of pounds of public and private investment, and ending the red tape that slows projects down by allowing developers to build their own connections.'And a Neso spokesman said: 'Keeping the lights on is not optional - we are legally required to keep electricity flowing securely across Great Britain.'The biggest opportunity to reduce balancing costs is the timely delivery of network infrastructure by transmission owners, which could halve those costs by the end of the decade.'