NHS Hospital saves 40% on energy costs with upgraded heating pumps

An NHS hospital in the Oxford area called Dura Pump to look at replacing some Holden & Brook Starflex Belt-driven Pumps with 37kW fixed-speed motors. The pumps were obsolete belt-drive models, which are typically considerably less efficient than comparable direct-drive models, often using 30-40% more power. Major challenges included:

1. Increasing efficiency 
2. Handling the large motors 
3. Ensuring continuity of service during the installation process

The Dura Pump team analysed the pump system and realised that there were massive energy savings to be made. We specified 2 Grundfos NB end suction pumps with 18.5kw motors, coupled with 2 Grundfos CU2 variable speed inverters. These pumps met the duty of the existing pumps while massively reducing power consumption.

We prefabricated the stainless steel pipework and base plates off-site to ensure a swift swap out of the pumps, then removed the old pumps one at a time, replacing them with the new Grundfos NB pumps and inverters. This included replacing the pipework, bellows and making all electrical and mechanical connections. We also provided a BACnet connection to the inverters so they could be controlled of the site BMS.

The new pumps met the hospital’s requirements but also saved them 194,472kWh per year, helping get them closer to net zero CO2 targets and saving them a large amount in running costs. For example, if the electricity costs them 33p per kWh, the average electricity cost in the UK, this would save the £64,175 per year, giving and ROI timeframe of only 6 months.

Additional benefits were the reliability of more modern pumps, reducing downtime and additional maintenance, with more readily available spare parts. Staff also reported greatly reduced noise in and around the plant room, improving the work environment for staff and patients.