The Institute of Refrigeration’s Sirach technology network met recently to discuss how the industry can work to reduce energy in a holistic way. Andrew Gaved reports
The IOR’s technology group Sirach (Sustainability in refrigeration, air conditioning and heat pumps) makes it its mission to bring together the academic and commercial spheres to share knowledge about the latest advances, and to ‘network’ in its proper sense of evolving new ideas.
The latest event examined the growing integration of cooling and heating technology as building owners and operators seek to reduce energy in a holistic way.
It was hosted by Wolseley’s Sustainable Building Center, an apt location, given the SBC’s aim to demonstrate commercially available green technology operating within a building setting.
The event was introduced by Robert Franklin of Climate Center, who proclaimed the business uniquely placed for such a discussion on integration, given the wholesaler’s range across cooling and heating (with sister company Pipe Center).
However, he noted that there were industry resourcing issues around the integrated approach, given the historical lack of overlap between the two supply chains.
The potential for heat pumps to transform energy use was well demonstrated by Stuart Tandy of Daikin UK, who discussed the company’s Cooling Award-winning hybrid heat pump.
The hybrid comprises a gas boiler front end and an air source heat pump, governed by an intelligent controller that runs either the most energy efficient option, or the cheapest option depending on the owner’s preference.
This, Mr Tandy noted, is a dynamic process: “The controller actively manipulates the hydraulics and the flow rate for the maximum heat pump efficiency.”
Because the hybrid is bivalent, it qualifies for RHI payments at the ASHP rate of 7.3p/kWh.
Heat pump choice
The concept was backed by the Sustainable Building Center’s Tim Pollard, who has worked closely with DECC over RHIs.
He said: “I believe air source heat pumps will become the most popular choice for wet systems, particularly with hybrid systems, because the public can be confident that should the heat pump ever fail, the boiler is there.”
Warwick University’s Professor Bob Crittoph described the latest advances in his department’s research into natural gas-fired heat pumps, which has the aim of replacing a conventional boiler, while consuming a third less gas.
The adsorption concept heats and cools activated carbon beds to change in system pressure, in place of a compressor and the current research activity surrounds the nature of the beds and the heat recovery between them.
The keynote presentation was made by Professor Ruzhu Wang of Shanghai Jiao Tong University, on solar heat pump technology.
Prof Wang outlined the great advances being made in China with integration of solar systems with cooling and heating technology. Among the innovations are residential buildings in Shanghai where the solar collection panels for cooling are built into the balconies, and even into awnings.
Prof Wang reported on advances in adsorption chillers for integration with solar collectors. A new 50 kW chiller, he said, using silica gel, had produced a COP of 0.6.
He concluded: “I have great expectations for air source heat pumps with small temperature differential fan coil units for apartments in China. When we consider our resources and the climate, heat pumps are a good solution, especially cities like Shanghai where there are hot summers and cold winters.”
The theme of heating and cooling integration will be continued at Sirach’s next event, taking place at Arctic Circle’s facilities in Hereford on 23 April. More details from