An immensely ambitious multi-phase project to decarbonise existing buildings at a huge hospital site, build new buildings, and design a site-wide energy strategy that meets 2030 emission goals.

About the project

Ushering in the Mater Misericordiae University Hospital’s (MMUH) ambitious decarbonisation roadmap, IN2 were appointed to provide full M&E services for the leading healthcare facility. The hospital is comprised of 206 beds and 15 operating theatres, as well as the newly established Rock Wing which features a 24-bed trauma ward. Due to the building’s age and central location, IN2 were faced with challenges across every aspect of the project.

The project, which included the development of a comprehensive Energy and Infrastructure Feasibility Study, aimed for a 6.3 GWh annual gas reduction and 2,500 tonnes of CO₂ savings per year, aligns with Ireland’s Climate Action Plan 2030, the Government’s Climate Action Plan 2025 objectives, and Net-Zero status by 2050. The MMUH is set to be one of the country’s leading healthcare facilities in energy innovation.

IN2's appointment is in response to the MMUH needing to comply with their legal obligations to achieve carbon emission targets detailed with the CAP 2024 targets and in accordance with the HSE Capital & Estates Infrastructure Decarbonisation Roadmap, June 2024

Key figures

110kV grid connection & bespoke 110kW substation negotiated with ESB
140No MV breakers
32No. Transformers
16No. Double Sub-stations
16MW standby gene (Dual fuel)

IN2’s Environmental Team responded to the proposed Development Control Plan – which proposed to build new hospital buildings, thus increasing the hospital size from 177,000m2 to 223,500 m2 - with a proposed decarbonisation strategy. After collecting building data and assessing energy usage and mechanical surveys, the team conducted energy modelling and assessed the effect of geothermal heat pumps and air source heat pumps, both of which didn’t meet targets on their own.

Instead, the team looked into creating two centralised energy centres – which could handle all current demands and future developments on site - in the East and West sides of the hospital. A combined solution of the centralised energy centres fortified with ASHP/s and GHP/s that replaced the gas boilers and combined heat and power unit (CHP) which would meet 2030 targets was decided upon.

The proposed Energy Strategy ensures all new developments are integrated within a robust, sustainable and future-ready energy network. IN2’s engineers delivered a comprehensive feasibility and design study encompassing both electrical and thermal infrastructure across the entire Mater campus. The work involved detailed load assessments, energy modelling and the development of decarbonisation scenarios designed to balance technical feasibility, cost and operational impact. IN2 were particularly involved in the budget strategy for the whole energy upgrade.

IN2’s scope included the review of existing CHP, boiler and medium-voltage (MV) systems, identification of upgrade opportunities and preparation of a Decarbonisation Roadmap aligned with national policy targets. IN2 developed a staged approach for replacing gas-fired systems with Air Source and Water Source Heat Pumps (ASHP/WSHP), supported by a new Central Energy Centre and a future-ready district heating network.

A key component of IN2’s role was the coordination of electrical infrastructure upgrades to increase the hospital’s Maximum Import Capacity (MIC) from 3.8 MVA to 14 MVA. This expansion enables the transition to electric heating systems and ensures long-term energy security for the hospital. IN2 also implemented dynamic energy simulations and carbon forecasting, providing the HSE with clear evidence-based metrics for decision-making and investment planning.

IN2’s contribution has ensured a robust, data-driven framework for decarbonising one of Ireland’s biggest and most complex healthcare campuses - and all whilst ensuring that the live site is operational throughout. This detailed roadmap balances environmental ambition with clinical reliability and financial viability and has shown how historic buildings can achieve net zero.