The Royal Shrewsbury Hospital is conveniently located on the outskirts of Shrewsbury in Shropshire. It provides a range of acute hospital services for people from Shropshire, Telford & Wrekin, mid Wales and further afield.
The Combined Heat and Power (CHP) scheme at Royal Shrewsbury Hospital has enabled the hospital to save more than £780,000 a year, simultaneously shrinking its carbon footprint by some 2,000 tonnes annually. These and other improvements are the result of a 1150kWe trigeneration system, financed and installed by green energy specialist ENER·G Combined Power .
Shrewsbury and Telford NHS Trust commissioned the new CHP system after an audit in 2004 showed the primary energy intensity (PEI) of the hospital was around 100GJ /100m 3 – significantly higher than the NHS target of 55 – 65GJ /100m 3 . Issues included: an elderly inefficient boiler plant; temperatures being too high throughout the hospital; different and mismatched HVAC control systems, and, aged lighting systems.
Additionally, the district heating main was asbestos lagged and needed replacing. CHP was quickly identified as the best way of improving the hospital’s energy efficiency, while boosting its prospects of obtaining grant funding for part of the project.
The Caterpillar 1150kWe gas engine CHP at the heart of the system provides both medium temperature hot water and steam. This is supplemented by a new composite boiler and two dual fired boilers, one of which was also replaced.
Another innovation saw the creation of a chilled water (CHW) ring main. This linked a variety of chilled water plant, including the new 700kWe absorption chiller, installed as part of the CHP scheme, helping to secure the supply of chilled water throughout the hospital, allowing maintenance of all chillers to be carried without affecting patient care.