This feature explores the efforts being made by The Leeds Teaching Hospitals NHS Trust to meet the Government’s net-zero ambitions,including forward-thinking designs for two new hospitals
The Leeds Teaching Hospitals is one of the ‘Pathfinder’ trusts in the Government’s New Hospital Programme (NHP), which will see the construction of 40 new and improved hospitals by 2030. The new hospitals building, designed by Perkins&Will, will create two state-of- the-art new acute care facilities – one for adults and one for children, as well as the UK’s largest single-site maternity unit – all one a single site at Leeds General Infirmary (LGI). And central to the plans is that the development will provide a carbon net- zero hospital, in line with the NHS’s challenging target of becoming fully carbon free by 2045. Speaking to hdm, Jonny Sylvester, the programme sustainability lead and senior project manager, explained: “Sustainability is at the forefront of the design of the new hospitals, with the carbon impact of the building minimised with the innovative use of industry-leading digital monitoring and measurement systems, and through the selection of materials. “Collaboration between the designers and the trust puts sustainable practice at the heart of everything and through this design we have created a long-life building that is adaptable to the changing nature of healthcare.” The existing LGI estate is made up of a number of buildings, some, like the Jubilee Wing, having been built in the 1990s, but others dating back more than 150 years.
These, while impressive in terms of architecture – such as the Gilbert Scott- designed original Leeds General Infirmary building, which Florence Nightingale helped to design – are no longer fit for purpose. Sylvester said: “The challenge for the new hospital is how do we heat and ventilate buildings while limiting the impact in terms of carbon emissions. “The existing site has a generating station that burns fossil fuels. “Our ambition for the new hospital is that it will be ‘net zero’ in terms of carbon from the day it opens. “And this has meant we have had to consider everything from how we heat and cool the building to its orientation and massing.” Taking elements of the passivhaus approach to building design, the team has positioned the building to make the most of natural light, using parametric modelling to track the rise and fall of the sun at different times of the year, so making the most of natural daylight and solar gain. Sylvester said: “Façade-to-glass ratios are very important. “A fully-glazed building looks great, but it can cause issues with overheating at certain times of the year. “A South-facing façade might need a 30% glass-to-façade ratio, while North-facing elements may need a 40% ratio. Modelling has helped us to understand this and to design the building to maximise solar gain, so we are not overloading some areas or making others too cold.” Additionally, technology is playing a key role in the plans. The tight footprint of the city centre site – just 9,000sq m – meant that ground source heat pumps were ruled out as an option, so the team is planning to introduce air source heat pump technology.
This ‘clean energy’ approach will provide all the hot water, heating, and cooling needed for the new hospitals and, as it uses a lot of heat recovery, the approach negates the need for chillers and other carbon-intensive systems. There are also plans for 2,000sq m of photovoltaic (solar) panels on the roof of the building. Sylvester explains: “This is an 18- storey building and we will have a lot of roof space, so it seems sensible to use this to help with our overall carbon reduction strategy. “We will be siting both the air source heat pump system and the solar panels on the roof, leaving more of the internal space for clinical functions.” Technology will also be used to reduce carbon emissions in other ways. Sylvester adds: “This will be a ‘smart’ building, so we are looking at using smart enterprise asset management sensors to monitor things like temperature, air quality, occupancy, and overall humidity. “It’s about making the building more reactive to its environment. “We don’t want to get to September and just turn all the heating on. We want to use technology to tell us when we need to switch heating on and off, thus making the whole approach more reactive to real-world situations.” But it is not just carbon resilience that is at the forefront of the designs. They also consider the very-real implications of climate change, which are affecting hospitals across the globe. Sylvester said: “The planned new building has been designed with climate resilience at the core and to withstand the forecasted climate of the year 2050. “In Leeds, specifically, we have seen more-frequent flooding events, rising temperatures, and droughts over recent years. “In July of this year, we experienced the hottest day ever in Leeds – 39c – which directly impacted on the comfort of patients and staff in our hospitals – particularly in our aging buildings. “So climatic loads, including wind loads and directions – micro-climate studies – have informed the design of the building’s sub and superstructure. “And the impact of extreme rainfall has been factored into drainage calculations undertaken in consultation with Yorkshire Water to develop a Sustainable Urban Drainage (SUDS) strategy for the site. “We can’t just direct floodwater into drains in the city.
It’s about how do we make it flow at a slower rate, so we will be looking at permeable paving and storage tanks so we can slowly release excess water back into the ground.” Demolition work on site is now complete, with the trust’s target of 95% of materials recycled exceeded by 3%. And the outline business case for the new hospital is currently with the Government NHP team for approval. It is anticipated the new hospital will be completed in late 2028, with the first patients moving in in 2029. Sylvester said: “We are confident that the new hospital will go ahead, and we will realise our vision for a net-zero carbon hospital that provides clinical excellence in an environment that is maximised for the comfort of patients, staff, and visitors. “The Government is still showing a commitment to the programme and as a trust we are totally committed to delivering these new hospitals.” Once the new hospital is completed, five acres of land and several listed buildings will be sold off, with plans to create a life science, health technology, and research village.