Consider a developer planning a new 50MW data center in the UK to service cloud or AI workloads. They’ve secured the land, their investors are ready, and there’s no shortage of customers who need the capacity. What’s missing is power. Contracted demand in Great Britain's connection queue more than tripled in under a year, from 41GW to 125GW, with data centers accounting for around 73GW of it. In hotspots such as West London and Slough, lead times already exceed ten years. Given the continued rate of cloud capacity growth and the speed of development in AI, a decade is too long.

Meanwhile, data center developers and operators are being asked more demanding questions. Local communities want to know if the development will compete with homes and businesses for scarce grid capacity. Will it increase emissions, or be noisy, or drain local freshwater? Nationally, consumers already paying some of the highest electricity prices in Europe want to know whether more data centers will push bills up or even lead to instability on the grid.

With the Environmental Audit Committee now asking what role renewables can play in cutting data centers’ carbon footprint, the sector needs fast solutions, and answers that withstand scrutiny.

For data center developers, waiting for the grid risks the loss of customers and revenue, and can ultimately threaten the viability of the project. Dedicated renewable generation is a sound long-term ambition, but wind and solar don’t produce around the clock, and a data center can’t pause its entire workload to suit.

Covering the last stretch of power demand with renewable power alone typically needs costly storage or backup infrastructure, and the cost rises with each step towards genuinely continuous supply. Opting for behind-the-meter fossil gas solves the timing problem, but it brings with it emissions, carbon pricing, planning objections, and reputational risk.

Each of these routes forces a compromise between speed and sustainability. While an electricity connection may take many years, major new projects typically connect to the gas grid within two years. That’s a massive advantage – especially if it can be used to deliver a gas that doesn’t originate from a fossil source.

Biomethane over the grid

That’s exactly the idea behind ‘sleeving’ sustainably produced biomethane through the gas network from the plants where it is produced, to major consumers who would otherwise be reliant on far less sustainable alternatives. Take an illustrative example where a data centre developer partners with a producer such as Future Biogas to build a new biomethane plant.

This plant would exist only because the developer has committed to buying its output, and that detail matters. The agreement would add new renewable energy supply to a market that is short of it, rather than relabelling existing supply – which is the practice now attracting regulatory scrutiny.

Suppose a developer is looking to deliver a 50MW data center, and they partner with Future Biogas to deliver a new biomethane plant. Suppose that new production site would allocate 151GWh of renewable biomethane to the data center. The biomethane is made on British farms, injected into the existing gas network and delivered to the site.

If a behind-the-meter fuel cell then converts it to electricity (at roughly 60 percent efficiency), the data center gains about 90GWh of sustainable power each year, which equates to just over a constant 10MW of power – about 20 percent of the 50MW data center’s total demand.

A fifth might not sound transformational, but it can energise the first phase of a project years before its full or partial power grid connection arrives. That can be the difference between a project that opens its first halls to customers and starts earning, or one that can’t secure power on a viable timeframe and risks failure. Once the grid connection arrives, the biomethane keeps supplying about a fifth of demand and the grid supplies the rest, adding resilience to the project with a robust and diverse power mix.

The environmental story

Biomethane has clearly evidenced environmental benefits when compared to fossil gas and many other energy sources. Fossil fuels take carbon from beneath the earth’s surface. When combusted, that carbon is released into the atmosphere. Rotational crops absorb carbon dioxide (CO2) from the atmosphere as they grow. When digested in an anaerobic digester, they yield biomethane for energy, biogenic CO₂, and digestate that helps reduce reliance on synthetic fertilisers.

With carbon capture, that CO₂ can be entered into permanent geological storage, permanently removing carbon from the atmosphere rather than merely avoiding emissions. By capturing and storing those emissions (CCS) we render the energy produced NOT carbon neutral, but carbon negative.

That changes our 50MW data center example from a story of faster energy to one of faster energy matched with dramatic carbon reductions for the whole project. If we assume the carbon intensity of grid electricity will be around 50 grams of carbon dioxide per kilowatt hour (gCO₂/kWh) in line with the UK’s 2030 Clean Power target, the 348GWh of grid electricity the data center still needs will have emissions equivalent to about 17,400 tonnes of carbon dioxide (CO₂) each year.

So here’s where it gets interesting. Permanent removals from the very same biomethane production plant would produce about 17,400 tonnes of carbon dioxide (CO₂e) each year – almost exactly the same as the carbon footprint of the remaining 40MW of grid electricity consumed which would leave net operational power emissions at or near zero.

There is a precedent for the kind of commercial agreement that data center operators need in place to make this happen. In 2023, AstraZeneca signed a 15-year gas purchase agreement with Future Biogas for a private, unsubsidised green gas supply. Today, Moor Bioenergy in Lincolnshire supplies AstraZeneca with around 100GWh of renewable biomethane each year, avoiding approximately 17,000 tonnes of CO2e that would otherwise have been produced from fossil fuels.

For operators, investors and their advisers, considering biomethane as a route to faster, cleaner power, three issues matter most:

• Additionality: The Science Based Targets initiative (v2) asks whether corporate actions create genuine new decarbonisation rather than simply reallocating existing low-carbon supply. A long-term offtake that enables a new biomethane plant to be financed and built meets the core additionality test: the buyer’s commitment directly and clearly underlines the creation of the emissions savings and removals.
• Traceability: Credible decarbonisation claims depend on being able to demonstrate, with robust and auditable evidence, the carbon intensity and sustainability attributes of the energy being consumed. Biomethane’s lifecycle carbon intensity can be evidenced and accredited, while its dispatchable nature avoids the half-hourly matching challenges that arise with intermittent wind and solar generation.
• Cost: Biomethane economics need to consider grid electricity, biomethane power and permanent carbon removal against the value of operating years earlier.

Public support for data centers is teetering, and in some places projects are being refused on environmental grounds. If the sector can’t show that projects will be built responsibly, they just won’t be built. Public licence to operate is now a key consideration. Biomethane probably won’t be the only answer for every site, but it can help data centers become operational sooner and with reduced environmental impact. More than that, it can support a shift in the perception of data centers from something that endangers the UK’s energy system to a resource that can help to improve it.

Future Biogas is partnering with green gas offtakers as it builds a new generation of UK biomethane plants with carbon capture and storage. For more information on any of the issues in this article, please get in touch.