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Decarbonising buildings

Reducing carbon emissions from buildings is one of the critical challenges facing the UK today. Why?

It’s simple. To reach net zero emissions, we must remove the fossil fuels we’ve used for centuries, such as oil and gas, from the heating and cooling systems in our buildings.

It’s time to consider switching gas boilers for heat pumps.

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Switching to Renewables

Heat pumps significantly reduce your carbon emissions by switching the heat source from gas to electricity.

Electric heat pumps are around four to five times more efficient than gas boilers and have lower maintenance requirements. And, unlike gas boilers, their energy source is carbon free.

If your building has boilers and chillers nearing end-of-life, replacing them with a heat pump system is the best solution.

Close up fan cage white mini-split condensers

Are Heat Pumps the Answer?

All new assets require investment regardless of the technology, but there are other costs to consider around a degasification project.

These may include modifications to the way heat is distributed around the building via duct and pipe work. Accommodating the increase in electrification may also need an expansion of your electrical capacity and upgraded electrical connections.

With heat, size matters. An accurate assessment of heat load requirements, which considers other energy efficiency measures, is a vital step. Taking this ‘whole building’ approach could reduce the capital cost enough to justify the investment case.

Extreme close-up of metallic heat exchanger rod

Designing the Right Solution

Mitie can help you transition to renewable heat, by designing the application of innovative technologies, securing funding and managing the risk.

We offer an estate development service to create a low carbon, asset replacement strategy for your building or estate portfolio.

Accompanied by a performance assured delivery plan, we design heat decarbonisation projects to suit the demands of your building portfolio.

White air conditioner units on a roof of industrial building with blue sky and clouds in the background

Towards a Low Carbon Future

We are helping our customers transform and future-proof their estates, by delivering networked heat and power, on and off-grid. We do this by:

  • Assessing the natural resources that support renewable heat and accommodating the rise in electrification.
  • Determining the right mix of technology and the best solution for replacing assets.
  • Blending renewable technologies like solar PV, and commercial heat pumps, to enable self-sufficiency and energy security.
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Heat Pump Technologies

Different heat pump technologies can be specified depending on available resources. Ground Source Heat Pumps (GSHP) and Air Source Heat Pumps (ASHP) are the most widely adopted.

A closed pipework loop of water/antifreeze solution is buried in the ground, either horizontally in trenches (coiled or straight lengths) or vertically via boreholes.

Heat is extracted from ambient air drawn across the external heat exchanger. Source temperature is dependent on prevailing ambient conditions and varies through the year depending on geographic area (typical average is 10°C).

A large-scale solution:

1.  Closed Loop: a closed pipework loop of water/antifreeze solution is sunk into a river, lake, or the sea.

2.  Open Loop: where water is extracted from a ground aquifer or river and passed through the heat pump (often with a sacrificial heat exchanger).

Typically for multiple and diverse users.

Uses heat from an aquifer and includes heat / coolth storage to allow multiple and diverse users to take heat and coolth from the network.

Heat recovery option.

Recovers heat from exhaust air, before the air is discharged to the atmosphere, to provide space heating and/or hot water.

Buildings must be well insulated and sealed from infiltration or have access to a source of exhaust air (e.g. computer/server rooms or inverters/transformers).


Commercial heat pumps are often eligible for funding support from government programmes, including IETF (private sector), PSDS (public sector) and the Green Heat Network Fund (GHNF).

It starts with data …

Starting with desktop reviews of data and site usage, we assess the feasibility and constraints of the decarbonisation project. This is what we need to get started:

  • Site access
  • Boiler, DHW & heat emitter details
  • 12 Months HH gas or heat data
  • 12 months HH electrical data
  • Electrical capacity details
  • Site plans and basic construction detail
  • Building occupancy data
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How can we help?

If you’re looking for more information, need to talk to someone about an enquiry or want to chat about your service needs, then you’ve come to the right place.

Please fill in our short form and a member of our team will be in touch.

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