Wolfson's ground-breaking zero carbon project

In June 2021, Wolfson College received a much welcomed £5m Government grant, to enable the college to launch an exciting project to eliminate carbon emissions from its fifty-year old Grade II listed estate. The catch? The college had just eight months to complete this ground breaking work. 

Wolfson’s Chris Licence, Diane Mackay and Femke Gow, reflect on the challenges of the project, including supporting on-site students during the work, plus the college’s plans to achieve net zero by 2024.

Wolfson’s Zero Carbon project has been a huge success, winning the 2022 Oxford Preservation Trust Award and the Vice-Chancellor's Environmental Sustainability Project Award. How did the project originate? 

We applied for the Public Sector Decarbonisation Scheme in spring 2021 – although we were already making notable efforts to reduce our emissions before receiving the grant.

The college is fully divested from integrated oil, coal and gas companies, as well as companies that derive revenue from the exploitation, ownership or extraction of fossil fuels. In our 2020 Estate Strategy, we made decarbonisation our top priority, commissioning an energy audit and decarbonisation plan.

The audit revealed that if we did nothing to reduce emissions, the college would have a twenty-year carbon footprint of 24,000 tonnes of Co2. This is equivalent to driving an electric car for 24,000 years, driving a diesel car for 14,000,000 km or 12,000,000 Co2 extinguishers being set off.

What actions did you take to eliminate emissions from the main estate?  

We replaced over 1,000 single-glazed windows with advanced triple-glazing and insulation. This led to an 80% reduction in energy required for space heating.  

In addition, we replaced Wolfson’s original gas boilers with the pioneering technology of Co2 heat pumps that run on clean electricity.

Wolfson College's old gas boiler

This reduced the main estate’s scope one (direct emissions from owned or controlled sources) and scope two (indirect emissions from the generation of purchased energy) carbon footprint to zero.  

Wolfson College's new Co2 heat pump

This is one of the UK’s largest heat pump programmes ever and one of the largest to be retro-fitted to an estate of this complexity. Avoiding environmentally damaging refrigerants, the heat pump selected uses Co2 in its sealed system, which works with a higher temperature difference than other refrigerants. This has the knock-on benefits of reducing flow rates around the system and needing smaller, cheaper pipe sizes. Wolfson is at the forefront of proving its efficacy on an estate of this size. 

A main objective of the project was to improve student accommodation blocks. How did you tackle this? 

As a graduate college that’s open all year, we carried out work on the accommodation blocks while students and staff lived and worked in the buildings. Due to the project’s short timeframe, we had to quickly develop a schedule to work through each block. Residents were given seven days’ notice to move temporarily into new accommodation while the work took place. 

To be effective and efficient, this quick turnaround required frequent and detailed communication channels to be established to help keep everyone informed. Our channels included:

• e-newsletters
• a project hub on our website that included project background, FAQs and live schedules for the work moving through each block 
• in-person briefings with each block before work started 
• presentations by the engineers and architects with Q&As 
• events to celebrate the milestones. 

Communication was crucial in reminding everyone throughout of why we, as a pioneering college, collectively decided to take on the challenge and pave the way for others. 

What were the biggest obstacles? 

Delivering the project during a pandemic and without closing the college was a huge challenge. Logistically, it was particularly difficult for the Accommodation Manager and Housekeeping team to quickly turn around room cleaning and housing reassignments in order to keep within the tight timescale. There was also a huge amount of work to complete, involving:

• 1,564 new radiator valves 
• 1,000+ individually cut bespoke pieces of glass
• 700m+ of new mains electrical cable 
• 600m+ of new pipework laid in service ducts and trenches 
• 9 district plate heat exchangers, and associated pipework, reduced to two main centralised units. 

Two of us, Diane and Chris, were new to our roles. So, we were still learning the day-to-day aspects of our jobs, college processes and policies along with managing this disruptive, large-scale improvement project. 

What have you learnt and what would you do differently with a longer timeframe?

Wolfson has delivered a very complex project in the middle of a pandemic and during the height of term time; a great achievement that is very unlikely to ever be repeated in the same circumstances. However, we weathered the storm, and we're proud of how we came through it. 

During the project, we realised that we needed to engage much earlier with our residents and other stakeholders, giving as much information and guidance as possible up front about the project. We learnt on the way, and as work progressed, we established much clearer and more defined communication channels. 

In terms of the technical aspects, we had to quickly learn to operate a very complex, innovative piece of technology and engineering design. If we were doing this again we would undertake more involved training ahead of the commissioning and hand over of the new heat pumps to help improve the process. 

Wolfson is aiming to reach net zero by 2024. What are your next steps? 

We’re currently insulating our original, flat-roofed main buildings to further cut heat loss. As funding becomes available, we’ll add photovoltaic (PV) panels onto the new roofing. Our existing solar panels cover a roof area of 135m²; installing PVs on all suitable roofs (980m²) will allow us to generate about 10% of our total energy demands locally. 

The college is also moving to all LED lighting and hopes to install a new 1MWh electrical storage battery, enabling it to draw electricity at peak “green” times and store energy for use later when it might otherwise have to draw from non-green electrical supplies. 

Our aim is to be totally carbon free with our heating and hot water services across all college properties in time for the 50th anniversary of the opening of Wolfson’s old main building in 1974.

The success of our recent project shows that the tide can be turned on climate change. One of Oxford’s biggest emitters can become net zero – we hope our work will inspire others across higher education and within the public sector.