Hospital savings prove to be more than hot air

Dec 31, 2011 | Heat Transfer

Harrogate Hospital is saving energy and improving patient comfort in its hydrotherapy unit thanks to a refurbishment which includes a compact Spirax Sarco EasiHeat steam-to-hot water system.

The EasiHeat system provides hot water to an integrated Calorex Delta 10 unit, which controls both the temperature of the pool and the temperature and relative humidity of the air in the hydrotherapy and swimming pool. The Calorex system incorporates heat exchangers, an air handling unit and a heat pump.

The heat pump recovers energy from excess moisture in the air above the pool to provide up to 25% of the heating energy needed in the pool room. The rest is provided by hot water from the EasiHeat system. The system maintains the pool temperature at between 34 and 36°C and conditions the air to a comfortable 30°C and 60% Relative Humidity.

The Spirax Sarco unit, which includes a plate heat exchanger, was chosen because it can use plant steam to provide a reliable supply of on-demand hot water at a precise temperature.

The decision to opt for a heating system based on steam was due to the fact that there was a ready supply of plant steam available, which was previously used in the shell-and-tube calorifier that heated the pool before the refurbishment.

In addition to the new pool room systems, the refurbishment also includes a second air handling unit bringing fresh air into the adjacent rest area, while an integrated building control system monitors and optimises the energy performance of the entire hydrotherapy unit.

The improved heat recovery, temperature and humidity control is expected to save over £2,000 per year in heating bills and almost 300 tonnes of CO2 emissions over the 15-year life of the plant.