Mitie Accelerates Decarbonisation Projects and Digital Twin Development with Hysopt

As a leading facilities and energy management company, Mitie is helping organisations across the UK reduce their carbon footprint through practical, measurable action. Their Plan Zero initiative sits at the heart of this mission, combining data, technology, and engineering expertise to decarbonise buildings at scale.

‍

When Mitie’s decarbonisation engineers first adopted Hysopt, they wanted a simulation tool that could combine technical precision with business impact. “The tool is amazing — invaluable when the right project comes up,” says Thomas Whittingham, who focuses on early feasibility and solution design. “It’s perfect for what we needed.”

‍

From day one, Hysopt proved its worth. The first project using the software identified enough energy and carbon savings to cover the entire investment — confirming its role as a key enabler in Mitie’s decarbonisation workflow.

Mitie’s decarbonisation teams use Hysopt at two critical points in their process. On the solutions side, Thomas and his colleagues apply the software during early-stage feasibility and bid work. Their focus is on high-level energy performance, carbon reduction, and cost savings — often under tight timelines.

‍

“Hysopt gives us system-level energy and carbon results that clients can immediately understand,” Thomas explains. “Even a 25% accuracy range is enough to grab attention and win work — the physics gives it credibility.”

‍

Meanwhile, the consulting side uses Hysopt for deeper analysis in Plan Zero roadmaps, detailed feasibility studies, and TM54 compliance. For George Yfantis, Mechanical Engineer at Mitie, this detail is a strength. “We rely on Hysopt for digital twins and TM54 projects because it shows how the system actually behaves — not just what it should do on paper.”

‍

By bridging these two approaches, Hysopt ensures that Mitie’s early-stage proposals and final designs share the same technical foundation — creating consistency from first pitch to project delivery.

Hysopt now plays a central role in Mitie’s digital twin proposition. While Mitie’s teams use IES VE for the building-side modelling, Hysopt provides the detailed HVAC layer that brings these digital twins to life.

‍

“Clients can see predicted outcomes before they invest,” George says. “We use digital twins to justify capital decisions, forecast energy savings, and revisit performance over time. Hysopt gives those models engineering accuracy — not just estimates.”

‍

By modelling pumps, heat pumps, circulation systems and hydraulics in detail, Mitie’s engineers can test different configurations and prove system efficiency before implementation. The result is greater confidence in investment decisions and long-term engagement with clients.

Across Mitie’s decarbonisation business, Hysopt has helped teams collaborate more closely and share insights between pre-sales and consultancy. Both sides value the ability to quantify energy and carbon savings using the same tool, ensuring alignment on design logic and sustainability targets.

‍

The software’s role continues to grow, particularly with the launch of Hysopt Feasibility — a faster workflow that enables Thomas’s team to perform early assessments in hours rather than days. “It’s exactly what we’ve been waiting for,” he says. “It will make the tool even more powerful at the bid stage.”

‍

Looking ahead, Mitie plans to expand its Hysopt use into more TM54 studies and digital twin projects, reinforcing its Plan Zero ambitions. As George puts it: “We like it a lot — it’s very good at what it does. The more we use it, the more valuable it becomes.”