Offshore wind could beat onshore wind on cost, but planning restrictions are key

Currently, onshore wind is one of the cheapest sources of renewable power. However, without change to planning restrictions, Cornwall Insight has estimated offshore wind is likely to surpass onshore wind power to be the new source of cheap renewable energy in less than ten years. Offshore wind has seen significant innovations, such as higher turbines with longer blades, allowing it to capture more of the wind. 

The graph below shows that the Levelized Cost of Energy (LCOE) falling below onshore wind by 2028. The projections are based on capital costs by technology, fixed and variable operational costs, expected hurdle rates and locational factors such as transmission losses and connection fees and using the current load factors for offshore wind at 58.4% and onshore wind at 38%.

A graph showing levelised cost of energy of wind technologies

Tom Edwards, Senior Modeller at Cornwall Insight, said:

“The renewable energy market is under a process of transition with onshore wind facing the real prospect of being usurped by its offshore cousin to be the cheapest source of clean power in the not so distance future.

“Improvements in offshore technology are occurring all the time and for offshore wind increasing the size of turbines is making a significant impact. With 8MW models currently being deployed, and larger 10MW and 12MW models under development as the technology advances. With these larger economies of scale, it is inevitable that costs will fall.

“However, the playing field is not level in Great Britain when it comes to these comparisons. Analysis by the Onshore Wind Cost Reduction Taskforce found that LCOE savings of between £4MWh and £7MWh were possible with tip height and rotor diameter optimisation for onshore wind. The latest turbine specifications claim to improve load factors by as much as 26%.

“While restrictions on onshore wind turbine height are maintained, projects will be unable to take advantage of these improvements to reduce costs. For onshore wind to keep pace with its offshore counterpart, planning decisions will need to be relaxed. This will not only to benefit consumers with cheaper cleaner energy but help the government towards its decarbonisation targets, not only in terms of facilitating the best conditions for new build onshore wind but also allowing existing sites to be repowered optimally.”