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The College is moving towards net zero operational buildings, subject to the constraints of available technology and funding. In 2023, the College commissioned a Net Zero Implementation Strategy, which included feasibility level studies to remove gas from all operational buildings. These projects are being incorporated into the College’s ongoing 10-year capital programme, and take into account the end of life of existing heating systems and the need to maintain sufficient accommodation for student use. 

During the 2024 Easter vacation, the first phase of a project to move Lerner Court (one of the College’s newer buildings) to Air Source Heat Pumps. The project was completed on time, within an extremely tight period to avoid any disruption to students. This initial phase has transferred the heating in student rooms and the hot water system to Air Source Heat Pumps, installed on the roof. At the same time, the College's in house team installed LED lighting to the majority of the student bedrooms. 

In early 2025, the second phase of works commenced. These works revitalised an existing network of boreholes, with new Ground Source Heat Pumps and a rearranged ground floor plant room installed. The building’s old Ground Source Heat Pumps had provided only limited heating, and primarily served a cooling function. The air handling units, which provide heating and comfort cooling to the conference rooms, were also replaced to enable the heating to run at lower temperatures. The gas boilers were fully removed, and back-up electrical boilers have been installed to provide additional resilience.

 During the first fourteen months of operation (April 2024 to May 2025)  

During the academic year 2022-23, a project was carried out at Braeside. This refurbishment project included fully insulating the building to reduce heat loss, and the installation of an Air Source Heat Pump. Additional student rooms were also created, and the existing facilities upgraded. The project was recognised with a Special Award in the 2022-23 Green Impact Awards at the University level.

Sustainability was put at the heart of the Braeside refurbishment project. The most sustainable building is the one that already exists. Buildings are responsible for 39% of global carbon emissions. 28% from operational emissions, from energy needed to heat, cool and power them, and the remaining 11% from materials and construction. Re-using an existing building is the best way of making good use of this embodied carbon. Retrofitting extends a building’s lifespan and provides an excellent opportunity to significantly reduce operational emissions. Braeside had been little changed since it was built in the 1920s. Pre-refurbishment, the building had a heat loss value of 38kW, which equates to an annual footprint of over 17 tonnes of CO2. The sustainability upgrades to the fabric of the building were designed to drastically reduce the heat loss to 12.5kW, that is, by two thirds. To achieve this the retrofit included:

• Upgrades to the building fabric (roof insulation, external wall insulation and window replacement)
• Upgrades to the mechanical and electrical systems (including a new heating and ventilation system
• Installation of an air source heat pump, which, given the College buys all of its electricity on a 100% renewables tariff, reduces the operational carbon footprint of this building to zero.

From October 2023 to June 2025, over 16 tonnes of CO2e have been saved by the project.

This property is a Victorian end terrace house, which provides accommodation for 5 students and had the College’s first air source heat pump installed in Summer 2022. Together with the improvements to the building fabric, this has made the building net zero in operation (the College purchases 100% renewable electricity). At the end of its first operational academic year, the fabric upgrades and heat pump meant a 75% reduction in overall energy use, and a £500 saving on utility bills compared with the last academic year.

The Carbon footprint project included a new system of carbon accounting, which better ranks the College’s emissions based on level of control. The scope system used for the footprint can be seen below.

The use of this revised scope system found c. 33% of emissions not previously accounted for.

Â鶹Éç’s emissions are dominated by a small number of sources – gas, electricity, food, and waste production. Together these account for 97% of the College’s footprint in the baseline (19-20) year. Of these, gas use was the single largest contributor to emissions, with the gas used at Memorial Court alone comprising 25% of the total footprint. This makes it clear that reducing gas use, and ultimately removing the College’s reliance on gas for heating and hot water, is crucial for the transition to Net Zero.

College emissions 2019-20 and 2020-21, Joey Bream

The College commissioned a Route Map to Net Zero from Element Energy in 2022. This drew on the carbon footprint project, with a focus on the College’s built estate and how to transition to low carbon heating.

The Route Map highlights the need for ‘fabric first’ improvements, making energy efficiency improvements wherever possible on the College’s estate. There is also a plan to transfer to electric heating, using a mixture of air-, ground-, and river-source systems. Owing to the age, historic importance, and listed nature of the College’s estate, this is a long-term project.

The highlighted interventions from the Route Map have been added into the Colleges 10 year Capital Programme. This includes the electrification of the heating in Memorial Court, the College's single largest source of emissions.