By Chris Binns, Director of Planning

Multiple news reports have warned that solar and wind power could “overwhelm” the UK’s electricity grid. This, however, risks drawing the wrong conclusion: that the UK has failed in its renewable energy policy. In reality, we have a system‑management challenge – one which is more manageable than meets the eye. 

Periods where renewable generation exceeds demand are not evidence that the UK is building too much clean power. They reflect a grid system that was never designed for the energy transition we’re now delivering. The grid was built for a centralised, fossil‑fuel era, which must now adapt to decentralised, weather‑dependent generation. Solar and wind are simply exposing those constraints more visibly, not causing them. 

 

Work is under way to revamp our national grid, but in the interim, capacity will be constrained 

National Grid are well aware of this long-brewing issue, which is why they are spending £60bn on the largest overhaul of Britain’s energy system in generations, comparable to rebuilding plumbing and wiring across the entire country. 

But in the interim, the grid network must operate reactively, dealing with peaks and troughs in renewable generation. Paying households and businesses to increase demand during periods of surplus generation should not be framed as an emergency measure. We should seek ways to store that energy and use it during periods of higher demand. 

For example, during “Storm Dave” over the Easter weekend, Great Britain discarded 5GW of Scottish wind power through curtailment due to constraints on the electricity transmission network between Scotland and England. Consequently, the lost Scottish energy was replaced in England with gas, resulting in both a waste of low-carbon energy and increased costs to consumers. This situation highlights a real-world example of curtailment, where renewable energy potential is not fully utilised due to infrastructure limitations. 

Unless the transmission network is upgraded, the system will be constrained. Battery storage can help but does not solve the wider problem of moving power where it is needed. The grid needs major reinforcement, including substations, lines, and cables to support a modern renewable mix – composed of wind, solar, hydrogen, and emerging nuclear/SMR options.  

Crucially, however, the UK energy sector needs better planning that is more cognisant of the realities of today’s grid.  

 

Planning and grid must now be intertwined 

For developers of renewable energy schemes, the strain on the grid will put more onus on them to justify their project’s viability. While deployment of renewable energy has accelerated in response to national policy on net zero and energy security, the spatial planning of generation, storage, grid reinforcement, and demand has struggled to keep pace.  

What this means is developers can no longer treat planning policy as a separate stage from securing grid availability. Grid and planning must be intertwined as two parts of the same delivery solution. This is important, because even if a scheme is acceptable in planning terms, it may still be constrained by grid availability. The grid might wait for planning, but planning does not always wait for the grid. That gap creates a bottleneck and uncertainty for developers, which can waste money on schemes that may never become deliverable.  

At Pegasus, we have been helping developers navigate the consenting process alongside the practical realities experienced when connecting to the grid.  They commonly land on several solutions that lower upfront risk and raise viability of renewable energy schemes. A few include: 

  • Taking time, early in the development lifecycle, to promote the right sites aligned with identified grid capacity. 
  • Early consultation with statutory consultees and the public to help establish the principle of development upfront. 
  • Masterplanning and designing projects that use power locally, instead of importing power from afar. 
  • Aligning renewable energy growth areas with grid upgrades. 
  • Co-locating battery storage with solar or wind farms to capture excess power. 

The real challenge is for planning to evolve from site‑by‑site decision-making to a wider system design – Local Area Energy Plans, for example, must be embedded into mainstream planning legislation. These measures would require the National Energy System Operator (NESO) to sync with developers and planners but would ultimately reduce the need for costly intervention and curtailment of renewable energys projects. 

 

What are the economic effects of the UK’s energy insecurity?  

In its latest World Economic Outlook, the International Monetary Fund (IMF) cut its estimate for UK growth in 2026 to 0.8%, down from its 1.3% estimate made in January before the conflict in the Middle East began. This is the largest downgrade of any of the world’s advanced economies. The IMF said that one of the main reasons for it is that because the UK is a net importer of energy, this makes it sensitive to rapid rises in energy prices.  

For a more specific example of how the UK’s energy system challenges affect the economy, over £270m has been paid out since the start of the Iran conflict to shut down windfarms in Britain, and to pay for other sources to replace lost energy. These ‘constraint’ payments often happen when a high volume of renewable power is generated without sufficient capacity in the transmission network to handle the power flow.  

The UK’s energy insecurity will also impact household finances. For example, the Resolution Foundation has estimated that higher energy prices, because of the conflict in the Middle East, mean that the median working-age household will be £480 worse off in 2026 than they would have been in the absence of the conflict.  

Adding further pressure to household finances will be the next Ofgem energy price cap. From July 2026, Cornwall Insight has estimated that the cap will rise by £196 per year. While this would be lower than initially thought, the cap would be £1,837 for an average duel fuel household and would represent an increase of 12% on April’s cap.

 

Reducing home-grown power will only expose the UK further to volatile international markets 

Demand flexibility is a normal feature of modern electricity systems and, done well, can reduce costs for consumers while improving overall resilience. The issue is not the principle, but whether it is being integrated strategically rather than used reactively.  

Questioning why more solar and wind is being built risks missing the bigger picture. The UK’s greatest energy vulnerability remains its dependence on gas, as geopolitical events Ukraine and more recently Iran, have highlighted. Curtailing clean, homegrown power will likely increase exposure to volatile international markets, rather than reducing it. 

Renewable power is not overwhelming the grid. It is telling us, very clearly, that energy planning now needs to catch up with energy policy. 

If you’re working on a renewable energy or grid project and want to speak with one of our experts – contact Director of Planning, Chris Binns, and Senior Director of Economics; Richard Cook.