Executive summary
- The UK’s electricity network faces growing pressure as data centre demand increases alongside wider electrification and the expansion of renewable energy.
- Much of the grid was designed around centralised power generation and largely one-way electricity flows.
- Battery storage, on-site generation and smarter energy management can all help, but they won’t solve the underlying problem of network capacity and connections.
Our sister magazine Electrical Insight hosted an Energy Storage event this November. It was virtual, so we could enjoy it from the comfort of our own homes (or offices), and even better – no driving, so no traffic.
In the concluding panel discussion on battery storage, net-zero buildings, next-generation energy technology and long-term energy security, I wanted to look beyond the battery. So I asked: ‘Even if battery technology continues to improve and we make significant progress on energy security, what are the wider structural challenges that could still prevent us from scaling the transition? What’s the main bottleneck?’
The answer? Two words. The grid.
‘We love talking about the grid,’ the host quipped. But, dear reader – we do.
Built for a different journey
The panelist continued to explain that for decades, much of the UK’s electricity network was built around a relatively straightforward arrangement: large power stations generated electricity and sent it out to homes and businesses. Basically, a one-way street.
Fast forward to today and things look rather different. We’ve got renewable generation coming from all directions, battery storage feeding electricity back into the network, buildings becoming more active energy users, homeowners producing their own electricity and selling back to the grid – and, of course, data centres consuming increasingly significant amounts of power
The grid has had to adapt, but the infrastructure wasn’t originally designed with this level of complexity in mind. And while modern networks can accommodate electricity flowing in both directions, that doesn’t mean every part of the system has the capacity to do so easily.
It’s a bit like trying to turn an old country road into a six-lane motorway while the traffic is still moving.
Rush hour on the electricity grid
For the data centre industry, this is becoming a particularly important issue.
AI, cloud computing and high-performance computing are driving demand for ever more digital infrastructure. But those facilities need electricity, and plenty of it. Finding a suitable site is no longer just about land, planning permission and proximity to customers. It’s also about whether there’s enough power available – and, crucially, whether it can actually be connected.
There’s a difference between having electricity generated somewhere in the country and having the network capacity to deliver it to the right place.
For developers, that can mean connection delays, costly infrastructure upgrades and uncertainty over when a project can become operational. A site might tick every box on paper, but if the electricity connection isn’t there, it’s not going very far – like Friday afternoon on the M1.
And data centres aren’t the only ones trying to get on the motorway. Homes, businesses, transport and industry are all increasing their demands on the electricity system. Suddenly, there’s quite a queue.
Can batteries get us moving?
Battery storage is often presented as part of the answer, and rightly so. It can store electricity when supply is plentiful and release it when demand increases, helping balance the network and make better use of renewable generation.
For data centres, batteries also have an important role in resilience and continuity of service.
But let’s not get carried away. Batteries don’t generate electricity, and they can’t magically create additional capacity in a constrained network. They can help manage the traffic, but they can’t build the motorway.
The same goes for on-site generation, renewable energy agreements and microgrids. All have a part to play, but none removes the need for investment in the wider electricity infrastructure.
Don’t get stuck in traffic
For starters, energy needs to be part of the conversation much earlier in the data centre development process – many agree on that. Developers need to understand power availability, connection times and future capacity before committing to a site.
There’s also an opportunity to look more closely at flexibility. Could certain workloads be shifted to make better use of available power? Could battery storage, on-site generation and smarter energy management help reduce pressure at peak times? And how can developers, network operators, energy suppliers and local authorities work together rather than trying to solve their own little piece of the puzzle?
When I asked the panel what could prevent us from scaling the energy transition, I got a two-word answer, the same two-word answer that applies to so many data centre quandaries: The grid.
The digital economy is accelerating, but the grid is still stuck in traffic.
