The number you have to understand first

Almost every cost argument about offshore wind comes down to one metric, and most arguments go wrong because the metric is misunderstood. It is called the Levelised Cost of Electricity, or LCOE.

LCOE is the average cost of every unit of electricity a power station produces across its whole life, once you add up what it costs to build, run, maintain and decommission, and divide by everything it generates. It is expressed in pounds per megawatt hour, written as £/MWh. One megawatt hour is roughly the electricity a typical home uses in three to four months.

It exists so that very different technologies can be compared on a single line. A gas plant burns fuel every day but is cheap to build. A wind farm burns nothing but costs a fortune up front. LCOE rolls those opposite shapes into one number you can hold side by side.

What LCOE leaves out

Here is the part most cost claims skip, from both sides of the argument. LCOE measures only what the generator itself pays. It does not include the cost of keeping the lights on when the wind drops, the backup plant that has to sit ready, or the extra grid needed to move power from far offshore to where people live. This is not a claim made by critics, it is stated plainly by the UK government’s own cost report, which says the measure cannot capture a technology’s impact on the wider system. So when you see a single low number for wind, treat it as the cost at the turbine, not the cost delivered to your socket.

Offshore wind against the alternatives

These are the UK government’s most recent modelled generation costs, for plants commissioning around 2030, published in January 2026. They are modelled estimates for a generic plant, not the price of any single project, and they exclude the system costs named above.

On the government’s own modelling, offshore wind generation is among the cheapest available and sits well below new gas once the cost of carbon is counted, and well below new nuclear. That is the headline supporters quote, and on this measure it is accurate. But hold it next to the next section, because there is a gap that has to be explained.

So why do auctions clear higher than that?

This is the fair challenge, and the one most explainers dodge. If the modelled cost is around £44, why did the most recent UK auctions award offshore wind contracts at closer to £82 to £91 per megawatt hour in today’s money?

The answer is that the two numbers measure different things. The modelled LCOE is a generic estimate of underlying cost. The auction strike price is what a real project, with real financing, real risk and a real supply chain, needs to commit billions of pounds today. The gap between them is mostly the cost of money and the recent spike in materials, interest rates and turbine prices. The government states this directly, its modelled costs are not a guide to auction prices, because auctions reflect financing, contract terms and project risk that the cost model does not. Neither number is fake. They answer different questions, and honest reporting shows both.

The twenty-year story, including the part that went up

The long view is the strongest fact offshore wind has, and it is also where selective storytelling is most tempting. Here is the full curve, the dramatic fall and the recent correction, using UK auction strike prices in 2012 money so they are compared on a like-for-like basis.

The story is not that wind keeps getting cheaper forever. It is that offshore wind fell by roughly two thirds in under a decade, reaching a genuine low around 2019 to 2022, and then rose again as interest rates, steel and turbine costs climbed worldwide. That rise is real and it is honest to show it. It is also largely cyclical, tied to the same global pressures that pushed up the cost of almost everything built in those years, not evidence that the underlying technology stopped improving.

Is it subsidised, and does that last forever?

Offshore wind in the UK is supported through a Contract for Difference, or CfD. It is worth understanding properly, because it is the single most misrepresented part of the whole subject.

A CfD fixes the price a wind farm receives for its power for a set period, currently 15 years. If the market price falls below that fixed price, the project is topped up. But if the market price rises above it, the flow reverses and the project pays money back to consumers. During the high gas prices of 2021 and 2022, offshore wind CfDs did exactly that, returning money to billpayers rather than drawing it down.

Two things follow. First, a CfD is a two-way contract, not a one-way handout, and calling it simply a subsidy misses half of how it works. Second, it is temporary by design. Each contract runs for 15 years and then ends, and the oldest support, from the system that ran before CfDs, is already rolling off. The bridge has an end date built into it.

Why this is part of the transition, not the whole of it

Offshore wind is not a complete energy system on its own, and pretending otherwise is how the public conversation goes wrong. Wind needs the rest of the system around it, the backup, the storage, the grid and the balancing, and those carry real costs that LCOE does not show.

What the honest numbers do show is this. The generation cost of offshore wind is low and competitive against the alternatives. It fell dramatically, rose recently with global inflation, and is supported by a mechanism that is temporary and that has at times paid money back. None of that is hidden, and none of it needs to be. The full picture is more persuasive than the headline, in either direction. That is what EOS Omnia is for, the facts, in context, open to anyone who wants to look.