An On-Site Energy Group company · UK / Ireland / Europe
Mission-critical power without the wait, or the capex.
Critical Energy finances, builds, owns and operates island-mode power and cooling for facilities that cannot fail. Engineered for up to 99.999% availability, operational in months rather than years, and delivered entirely off your balance sheet.
Why we exist
The wait for power has become the constraint on digital infrastructure. Grid connections are quoted in years. Critical loads are planned in quarters.
For a data centre, every quarter without power is capacity that cannot be sold and compute that cannot be deployed. Connection queues, reinforcement works and moving energisation dates have turned the grid from a utility into a project risk.
Critical Energy exists to remove that risk. We deliver on-site generation that powers your facility independently of the grid from day one, with cooling and lifetime asset management included, under a single agreement that requires no capital from you.
Time from decision to power
Indicative, UK
The proposition
Three promises. One agreement.
Engineered for continuity
Solid oxide fuel cells generate power electrochemically, with no combustion and no single point of failure. Modular arrays provide layered redundancy, with availability guarantees of up to 99.999% matched to your uptime requirement.
Months, not years
Typical time to power of six to nine months. Island-mode deployment means no connection queue, no reinforcement works and no energisation date that keeps moving. Power arrives on your programme, not the network's.
Our capital, not yours
A single long-term Energy Supply Agreement covers generation, cooling and asset management at a lower cost of energy than grid. We fund, own and operate the assets. You buy guaranteed power, not a power station.
Availability, in plain terms
Every extra nine is an order of magnitude.
Availability is quoted in nines, which hides how much is actually at stake. Expressed as downtime per year, the difference between a good target and a critical one becomes obvious.
The technology
Engineered around solid oxide fuel cell technology.
Critical Energy generates power electrochemically rather than by combustion, using solid oxide fuel cells built for continuous duty on sites where interruption is not an option.
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No combustion
Electrochemical conversion produces power without flames, turbines or moving parts, and without NOx, SOx or particulate emissions.
30 to 40% less gas
Higher electrical efficiency than gas engines or turbines for the same output, cutting fuel consumption and the carbon footprint that comes with it.
Waste heat becomes cooling
Heat recovered at 370°C drives absorption chilling, converting a by-product into cooling capacity and reducing the electrical load of your cooling system.
20-year operating life
Modular stacks are refreshed in service across a two-decade design life, so performance is maintained across the term, not allowed to degrade.
Simplified permitting
Exempt from ETS, MCPD and EA emissions permitting in the UK, removing consenting steps that add months to combustion alternatives.
Future-proofed
The platform is ready for hydrogen as a fuel and for efficient carbon capture, protecting the investment case as regulation and fuels evolve.
Flexible operating modes
Load track, microgrid and fully off-grid configurations, deployed to match the resilience architecture your facility demands.
Energy-dense footprint
Up to 100MW per acre, delivering utility-scale capacity within the boundary of a constrained site.
The complete solution
Power, cooling and asset management. Delivered as one.
One agreement covers generation, cooling and operation for the life of the contract. Each stage is engineered against the same availability target.
Resilient power
Modular solid oxide fuel cell arrays sized to your critical load, with redundancy and availability guarantees defined by your uptime requirement, not a standard product tier.
Energy-efficient cooling
A complete cooling solution under the same agreement, from absorption chilling driven by recovered heat to mechanical chilling and aquifer thermal storage where site conditions allow.
Lifetime asset management
We operate what we build for the life of the agreement, with performance monitored through our Group's in-house asset management platform and reported against guaranteed levels.
Island-mode by design
Our first deployments run fully independent of the grid. No connection application, no import capacity negotiation, no exposure to network constraints or non-commodity charges. Your facility's power arrives when your facility does, and its availability is determined by engineering under our control, not by infrastructure outside it.
The commercial model
Zero capex. One agreement. Guaranteed outcomes.
Critical Energy delivers under a long-term Energy Supply Agreement, a behind-the-meter power purchase structure that transfers delivery, performance and technology risk to us.
You pay for the energy you use at a rate below grid-delivered power, with significant savings over the life of the agreement and none of the capital cost of building generation yourself. The assets, and the risk that comes with owning them, sit off your balance sheet and on ours.
Because we are the investor as well as the engineer and operator, our returns depend on the plant performing for decades. Our incentives and your uptime requirement are the same thing.
We fund
Project capital raised and deployed by us, with the backing of our Group's institutional investors.
We build
Design, consenting, procurement and construction managed end to end, to a committed energisation date.
We operate
Availability guaranteed contractually and managed 24/7 for the life of the agreement.
You consume
Resilient power and cooling at a lower cost than grid, under a single supply agreement.
or in development
Critical Energy is part of the On-Site Energy Group, leveraging the Group's knowledge and experience in delivering large, complex energy projects on demanding industrial sites. Backed by Downing, one of the UK's most experienced energy infrastructure investors.
Who it's for
Built for facilities that cannot afford to stop.
Critical Energy is a specialist, not a generalist. We are the right partner when three things are true:
Your load is very large
Sites from 10MW upwards, where scale demands utility-grade delivery inside the fence.
Downtime is unacceptable
Facilities where availability is measured in nines and interruption is measured in consequences, not inconvenience.
Speed determines value
Programmes where time to power decides whether the project happens at all.
Data centres, from hyperscale and AI compute to colocation, are where these three pressures meet, and they are our primary focus. The same model serves other mission-critical facilities at comparable scale.
Three markets, from day one
Critical Energy launches simultaneously across the UK, Ireland and Europe, targeting the markets where digital infrastructure growth is most constrained by grid capacity.
Start the conversation
Talk to us before the plan is fixed.
Whether your project is at site selection, in design or already stalled in a connection queue, an early conversation tends to widen your options.
Critical Energy
1 Old Hall Street
Liverpool, L3 9HF
United Kingdom
United Kingdom · Ireland · Europe