Nuclear RAB Levy Explained

What the Nuclear RAB Levy Is

RAB stands for Regulated Asset Base. It’s a funding model the government uses for large infrastructure projects where the upfront costs are enormous and the payback period stretches decades into the future. The same model funded the Thames Tideway Tunnel (London’s super sewer) and Heathrow Terminal 5. Now it’s being applied to nuclear energy for the first time.

The idea is straightforward. Building a nuclear power station takes over a decade and costs tens of billions of pounds. Under the old approach, developers took on all the financial risk during construction and only started earning revenue once the station was generating electricity. That made private investors nervous. They demanded higher returns to compensate for the risk, which pushed up the cost of the whole project. Hinkley Point C was funded that way, and the financing costs spiralled.

The RAB model flips that around. Instead of making investors wait ten-plus years before seeing any return, money is collected from bill payers during the construction phase. That steady income stream reduces the risk for investors and lets the project borrow at much lower interest rates. The government’s argument is that even though you’re paying now for a power station that won’t generate electricity until the mid-2030s, the total cost to consumers ends up lower than if the project were financed the old way.

In practice, you’re subsidising construction risk on behalf of institutional investors now, in exchange for cheaper low-carbon electricity once the station is running sometime in the mid-2030s.

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Why You’re Paying During Construction

You’re paying for something that doesn’t exist yet. That’s the bit that trips people up.

The government’s logic is about financing costs. Nuclear projects are so expensive that the interest payments alone can add billions to the final bill. By collecting revenue during construction, the project’s debt costs less to service. The Office for Budget Responsibility has estimated that the RAB model could save consumers money over the lifetime of the plant compared to the approach used for Hinkley Point C.

There’s also an energy security argument. The UK needs reliable baseload power that doesn’t depend on gas imports or weather patterns. Nuclear fills that gap, and the government wants to keep majority control over the project rather than relying entirely on foreign investment. Spreading the construction cost across all electricity users makes the project politically and financially viable in a way that pure private funding couldn’t.

None of that changes the fact that it’s an extra cost on your bill right now. But understanding the reasoning behind it at least explains why the charge exists and why it isn’t going to be reversed.

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What It Actually Costs

The levy is consumption-based. You pay per kilowatt-hour of electricity you use, not a flat fee. The rate is set quarterly by the Low Carbon Contracts Company (LCCC) and has been sitting between £3.50 and £4.50 per megawatt-hour since it launched. That works out to roughly 0.35p to 0.45p per kWh.

For a small office or shop using around 25,000 kWh a year, that’s somewhere between £85 and £115 annually. Not huge, but you notice it. A mid-sized operation consuming 150,000 kWh a year is looking at £525 to £675. A large commercial site pulling 500,000 kWh will see an additional £1,750 to £2,250 on the annual bill.

Those numbers are manageable on their own, but they sit on top of every other non-commodity charge you’re already paying: network costs, capacity market charges, climate change levy, feed-in tariffs. Each one feels small in isolation. Stacked together, non-commodity charges now make up a significant portion of the total electricity bill for most businesses. The RAB levy is the newest addition to that stack.

The rate is expected to rise over time as construction on Sizewell C intensifies and capital requirements grow. The LCCC publishes upcoming rates at least 30 days before each quarter starts, so you do get some advance notice.

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How It Shows Up on Your Bill

The nuclear RAB levy sits under the non-commodity or third-party charges section of your electricity invoice. Some suppliers itemise it separately. Others roll it into a broader line alongside other pass-through costs. If you’re on a pass-through energy contract, you’ll see it move every quarter as the LCCC adjusts the rate.

Even if you’re on a fixed-rate deal, check the small print. Many fixed contracts include clauses that allow the supplier to pass through new or increased statutory levies outside the fixed unit rate. That means your headline rate stays the same, but additional charges can appear on the bill that weren’t there when you signed. The nuclear RAB levy is exactly the kind of charge that triggers those clauses.

The collection process runs through EMRS (EMR Settlement Ltd), which handles the invoicing between suppliers and the central fund. Your supplier collects from you and passes it on. They don’t have discretion over the amount.

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Who Doesn’t Have to Pay

Almost nobody is exempt. The levy applies to every electricity connection in Great Britain, domestic and commercial.

The one exception is businesses that hold a valid Energy Intensive Industries (EII) exemption certificate. These are typically heavy manufacturers in sectors like steel, glass, paper, and chemicals where electricity represents a huge proportion of operating costs. The qualification criteria are strict and the exemption isn’t automatic. If you hold a valid certificate, your supplier should apply the exemption to your account.

For the vast majority of UK businesses, including offices, warehouses, shops, and restaurants, there’s no way around this charge. It’s statutory. Every supplier collects it. Switching suppliers won’t remove it.

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What You Can Do About It

You can’t switch your way out of the nuclear RAB levy. Because it’s a statutory pass-through charge, it applies regardless of which supplier you’re with. If you see a quote that looks suspiciously cheap, check whether they’ve included all pass-through costs or whether those get added on top.

The only direct way to reduce what you pay is to reduce your electricity consumption. Fewer kilowatt-hours means a smaller levy charge. That’s true of every consumption-based non-commodity cost on your bill, not just this one. If you’ve been putting off an energy efficiency review, this is one more reason to get it done.

Beyond that, the practical response is budgeting. Factor the levy into your annual energy cost projections. Use your historical consumption data and the current LCCC rate to estimate the charge for the next twelve months, then leave a buffer for rate increases. If you’re managing energy across multiple sites, an energy procurement strategy that accounts for both commodity and non-commodity costs will give you a clearer picture of what you’re actually spending.

The nuclear RAB levy isn’t the biggest charge on your bill. But it’s a permanent new fixture, and the rate will rise as Sizewell C’s construction progresses. Knowing what it is and building it into your planning is about all you can do.

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Key Takeaways

✓ The nuclear RAB levy is a mandatory charge on all UK electricity bills, funding the construction of Sizewell C

✓ It started appearing on invoices in late 2025 and applies to electricity only, not gas

✓ The rate is set quarterly by the LCCC and currently sits between £3.50 and £4.50 per MWh (roughly 0.35p to 0.45p per kWh)

✓ The RAB model collects money during construction to reduce financing costs, on the basis that it’s cheaper for consumers long-term

✓ Only businesses with a valid Energy Intensive Industries exemption certificate are exempt

✓ Switching suppliers won’t remove the charge because it’s statutory

✓ Reducing electricity consumption is the only direct way to lower what you pay

✓ Expect the rate to increase over coming years as construction ramps up

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