To help achieve climate-neutral building stock by 2050 the healthcare sector is being challenged to reduce operational energy use. By increasing the use of renewable energy supply and prioritising on-site renewable energy sources the hope it to reduce both harmful carbon emissions and operational costs.

There is no doubt that being more sustainable comes at a cost. Whether in the form of new build projects or the refurbishment of existing, yet ageing facilities, understanding the necessary capital investment, operational savings and payback periods is key to developing a workable sustainability strategy.

Because of ubiquitous need for hot water, from basins to baths and showers, catering and wash down, addressing how this resource is secured is one of the best ways of making active carbon savings today.  

Addressing the efficiency of domestic hot water (DHW) systems - whether through the implementation of heat pumps, solar thermal, direct electric water heating or even simple modernisation of existing gas appliances - helps properties meet sustainability goals in a practical and cost-effective manner. It also delivers improved year-round conditions for residents and staff, providing spaces better suited to delivering quality care.

For buildings already on gas and that rely on large amounts of DHW silent solar preheat is the preferable option. For new build properties, the expectation is for specification to default to a mixture of heat pumps and direct electric afterheat. New system approaches, including prefabricated packaged plant rooms, also provide for better use of the spaces that already exist, without the need to undertake expensive and disruptive building projects. This is especially valid as demands for larger accommodation space comes at a premium.

The current government’s renewable technology of choice is the heat pump, of which the easiest and lowest cost to implement is the air source heat pump (ASHP). The technology uses a reverse refrigerating circuit to extract heat from the air, even when ambient temperatures drop during the winter months. However, heat pumps are designed ideally to operate at low working flow temperatures (35°) to supply radiators and underfloor heating, not the more stringent heating requirements of water (+60°C) required to prevent legionella. Heat pumps will therefore demand more electrical energy to run the compressor to maintain the higher working flow temperatures required by commercial grade water heating applications.

This additional electrical energy required to raise temperatures comes from the grid and remains far more expensive than gas. In the past three years, electricity prices have fluctuated and climbed from three to nearly five times the cost of gas. This means transitioning to low-carbon technology can deliver considerable increases in operational costs if not approached with care and consideration.

Heat pumps have a valid role to play, but for water heating, they need to be used as part of a wider process to ensure cost-effective, efficient operation. This hybrid approach employs the ASHP as a source for preheating cold water flowing into the system to 45°C. This is more than achievable for most heat pumps, maximising the efficiency and reducing the energy required to run the unit.  Top-up heating to +65°C is supplied by gas water heater, gaining very low operational costs, but a less meaningful reduction in carbon emission. Preferably an electric boiler with smart controls to optimise the two heat sources will be deployed, minimising energy demands and providing better control over operational costs.

With a hybrid system, there will be increased plant, with a heat pump, boiler and larger cylinder needed to account for slower system reheat after peak demand. However, latest generation of monobloc ASHPs and electric boilers are increasingly more compact, while smart controls maximise storage optimising cylinder size.

For smaller to mid-sized hot water demands, typically seen in GP’s surgeries and smaller care homes, Adveco has redefined this approach with its award-winning FUSION electric water heating system. Conceived as a direct replacement for older gas systems, FUSION mounts an electric boiler onto a cylinder with prebuilt pipework, and the option for an air source heat pump, controls and/or immersion for added resilience.

For larger buildings a more bespoke system is likely to be required, although the basic premise remains the same, using ASHP preheat and a secondary energy source, preferably electric. It may also be possible to integrate solar thermal technology as a mid-heat to further cut energy demands, by as much as 30% annually to further offset operational costs and reduce emissions.  

Adveco can help achieve emission reduction targets today through lower impact building works.  With more than 50 years of specialised expertise in designing, supplying, and servicing hot water systems for hospitals and residential healthcare, Adveco is the single resource you need for independent expert technical guidance on choosing pre-sized or bespoke sustainable applications today to get you on the right path towards net zero operations.