Every few days I sit across the table from an engineer deciding whether to join us, and the question underneath their questions is always the same: will the work here actually stretch me, and will I be glad I stayed?

I like that question. It’s the right one to ask, and it’s one I can answer honestly, because it’s the same question I asked when I joined this industry.

Peter Östlund, Managing Director – Europe

A business that has already done the hard part

Recruitment pitches are easy to write and hard to trust, so I’d rather start with what we’ve actually built. As specialists in turnkey high-voltage grid connections, substations, and cable routes, JSM Group designs and delivers complex 110kV cable routes and state-of-the-art substations across UK, Europe and beyond, the kind of work that has to be right first time, because it sits underneath hospitals, industry, and homes that don’t get to notice when it’s done well.

Our work near Berlin is a good example of what that looks like in practice. We’re building a 110kV high-voltage substation and around 6km of company-owned cable route to bring a 200MW grid connection, with room for further expansion, powered from renewable sources via the regional distribution network. The interesting problems on a project like that aren’t really about voltage or civils in isolation, they’re about sequencing: how you route a cable corridor around constraints that weren’t there when the network was first designed, how you keep a substation build on programme when three other contractors are working the same site, how you hand something over that the client’s own engineers will still trust in up to forty years. That’s the work. It’s rarely glamorous in the moment, and it’s exactly why I trust the people who do it.

That track record matters for recruitment, not just for client confidence. People deciding where to build a career want evidence that the business they’re joining has actually delivered under pressure, not just described itself well. We can show that.

This isn’t our first stretch of growth

It’s also worth saying plainly: expanding into new markets isn’t new territory for us. JSM started in 1998 as a specialist subcontractor in London, was promoted to Tier-1 contractor status in 2009 and has grown into a business of 300+ people across EMEA opening in each of those markets within the last few years. That growth has been backed by serious investment, from Rutland Partners in 2021 and, more recently, TowerBrook Capital Partners, and it’s brought us to where we are today: a business rebranding and expanding with real momentum behind it. Extending JSM across Germany and the EU is the next chapter of that story, not a first attempt at one.

I think that history matters to anyone deciding whether to join a growing team. It’s a fair question to ask, has this business actually done this before, successfully, more than once – we have.

Growing into one of the defining sectors of our era

In my opinion, now is a genuinely interesting moment to join us: we are expanding across Germany and the EU, because of where the demand is coming from. Hyperscale data centres, the kind now running AI workloads and complex data analytics, need grid connections and substations built to a speed and reliability that most networks were never designed around, and the wider energy transition, renewables integration, electrification, new industrial demand, is asking the same of the grid at once. From complex 400kV cable routes to state-of-the-art substations, our engineering solutions are the critical foundation underneath both of those stories. We’re not adjacent to the modern digital economy, we’re the infrastructure that’s enabling it.

Building from the ground up

Expansion means something specific for the people who join us now: real scope for initiative. Joining a business that’s still building out its EU footprint is a genuinely different experience from joining one that’s already settled into its final shape. You’re not stepping into a fully defined role in a fully defined structure; you’re helping build both. That means high-impact infrastructure projects early, real ownership of challenges rather than a slice of one, and the chance to shape how a growing business solve things, not just execute someone else’s playbook.

The culture that makes the delivery possible

None of the above works without the right culture underneath it, and this is the part I’m most protective of. JSM Group is built on ‘From Concept To Connection’, and I take that literally: the engineers who help shape a solution are the same people who see it through to energisation, not handed off partway through to somewhere else in the business. That continuity is deliberate. It’s how people build real ownership of their work, and it’s how more experienced colleagues end up genuinely invested in developing the people around them, because they’re still on the project when it matters.

It also means we’re honest about the trade-offs. This work is technically demanding, sometimes unglamorous, and the timelines are real. What we offer in return is genuine responsibility, colleagues who know the job, and a business that’s growing fast enough to need you to help shape it.

If you’re deciding where to build your career

If you’re an engineer weighing up where that next stretch of your career happens, I’d rather have that honest conversation than send you a polished pitch. Check out our projects, talk to the people who’ve been in the trenches on our projects, and judge for yourself.

Read more about our work in Europe.

Check out our current vacancies.

Moving a transformer isn’t just a lift, it’s a sequencing exercise, and it’s where deep high-voltage plant installation experience earns its keep.

We’re proud to be supporting Principal Contractor, Sweet Projects, on the installation of transformers and associated ancillary equipment within a substation currently under construction, on a programme with no room for slack. Work like this draws on years of specialist experience in high-voltage plant installation: knowing how to sequence heavy lifts, protect live and incoming infrastructure, and keep a build on track without compromising safety.

The lifts themselves required a 750-tonne mobile crane and careful coordination to manoeuvre the equipment through both temporary and permanent steelwork, work that only came together through close collaboration between our electrical installation team, lifting specialists, structural engineers, steelwork contractors and the wider construction team.

Behind the lift was a just-in-time logistics strategy: every component delivered in sequence, timed against the programme and site constraints. That kind of precision, coordinating suppliers and hauliers so the right equipment lands at the right moment, is second nature to teams who’ve done this at scale, again and again.

Planning like this rarely makes the headline, but it’s what makes complex high-voltage installations like this land safely and on time.

JSM Group, a leading provider of integrated utility infrastructure solutions, has commenced construction of the high voltage substation and cable route for maincubes’ new data centre campus in Nauen, Germany. The start of works follows the granting of the building permit for the energy infrastructure and represents a major milestone in the delivery of the mainHub Berlin campus. JSM Group is responsible for the delivery of the company owned 110 kV cable route and substation – critical components that will underpin the campus’s long term energy security and scalability. The approximately six kilometre cable route will transport electricity from renewable energy sources via the modern E.DIS distribution network to the site’s 110 kV substation.

Enabling high performance infrastructure for cloud and AI

The new campus has been designed with a grid connection capacity of 200 megawatts (MW), with further expansion options, to support high performance computing environments, including advanced AI workloads and complex data analytics. Through the delivery of this critical energy infrastructure, JSM Group is enabling a resilient, future proof power supply aligned with the demands of next generation digital services. maincubes selected Nauen as the site for its new campus due to the Berlin Brandenburg region’s stable energy supply, strong renewable generation from wind and photovoltaics, and favourable conditions for sustainable growth. The project further strengthens the region’s position as a hub for modern digital infrastructure. Oliver Menzel, CEO of maincubes, said:
The start of construction of the substation is the next visible step on our journey toward mainHub Berlin. In Nauen, a state of the art data centre location is being created – regionally rooted and internationally connected. In doing so, we are consistently continuing the success story of maincubes and reinforcing our commitment to sustainable, energy efficient and resilient digital infrastructure.
Michael Booth, CEO of JSM Group, commented:
This project highlights JSM Group’s capability to deliver complex, high voltage energy infrastructure for mission critical environments. Data centres of this scale demand absolute reliability, technical excellence and close collaboration with our partners. We are proud to be playing a central role in enabling maincubes’ expansion in the Berlin region and supporting the delivery of sustainable, high performance digital infrastructure.
Dr. Michael Wiebersinsky, Mayor of the City of Nauen, added:

With the new data centre campus, our region is developing into a highly modern location where future innovations can emerge. From a sustainability perspective, it gives me confidence that Nauen will be a reliable partner for the operating company maincubes.

Hanjo During, Managing Director of E.DIS Netz, said:
With the campus currently under development, we will connect a particularly high performance data centre to our regional electricity distribution network. With the campus planned here in Nauen, the connected capacity will increase significantly in the future.
With the Nauen development, maincubes continues to expand its presence in the capital region, building on the successful operation of its first Berlin data centre, BER01.