Green energy technology services provider New Southern Energy (NSE) is looking to supply and install energy efficient water heating systems, including heat pumps, at a number of hospitals owned by South Africa-based private hospital operator Life Healthcare, NSE director Deepak John tells Engineering News.

NSE has offered to finance the equipment supplied to Life Healthcare, which can be paid off based on a kilowatt-hour used rate, an option not previously taken up by the hospital group.

NSE completed projects at two hospitals in the Life Healthcare group in early 2012. This was followed by a R4.5-million contract in August 2012 to supply and install heat pumps at five other hospitals in the group, with projects also completed at two more hospitals in mid-2013.

The projects involve replacing the existing hot-water systems with heat pumps to efficiently heat the water, which is stored in polyurethane tanks for improved heat retention, John explains.

“The heating elements in calorifiers, which are significantly large geysers, were replaced by heat pumps at the hospitals,” John says, adding that heat pumps have a heating element similar to that of geysers, but the pumps also heat water by transferring thermal energy from the surrounding air into the water using a device that functions in a similar way as an air-conditioning system. “This enables heat pumps to use up to three times less electricity than geysers when heating water,” he explains.

Each hospital, John adds, required different solutions, owing to the size and setup of their existing water systems.

Some of the calorifiers at the hospitals were old and had poor heat-retention capabilities. These were replaced with a geyser matrix system, as access to the boiler rooms where these calorifiers were installed was limited, he notes.

“The geysers are connected in a grid to ensure that the hospitals are supplied with enough water to meet their requirements. The design is also modular, allowing for additional geysers to be installed if any of the hospitals expand. “Also, access to water services will continue, should one of the geysers be replaced, as the other geysers in the system will still provide water,” explains John.

He points out that the Life Westville Hospital, in KwaZulu-Natal, was a particularly challenging project, as the water distribution system was poorly designed. “There were more than 200 geysers at different locations in the building, which is extremely inefficient, as each geyser requires electricity to heat water.

NSE provided the hospital with a large central storage system, with a capacity of 15 000 ℓ, which was fitted with three 45 kW heat pumps. NSE also installed piping from the central storage system to all the areas that required water, which resulted in all the geysers being decommissioned.

“Having a centralised storage system offers greater efficiency, as all the heating is done in one place instead of being spread out over the whole building,” says John.

He notes that the systems that NSE installed at the Life Healthcare hospitals provide return on investment in 18 months.