JZ Flowers has Priva-controlled pack-house

"Traditionally, with this sort of plant, the heat produced by the 'condenser side' of the chiller is dealt with using a dry cooler to get rid of the waste heat," explains Mr Grant. "However, at JZ Flowers, this heat is instead diverted to a buffer tank. The hot water in the tank is then used to provide the heating for the offices, amenity areas and the production area (kept at 18˚C). Heat is only destroyed when the buffer tank is satisfied or not required."

The clever part here is to use the Priva BMS to decide on the optimum temperature at which to maintain the buffer tank, and to this end, the buffer temperature is only calculated as high as it needs to be, and no more.

The buffer tank also acts as a source for under-floor heating in the office and amenity areas, although each individual office and the canteen also feature fan coil units to top up the heat as required, or these can be switched to use chilled water for cooling too - all under individual control using Priva's 'Comforte' range of modules and Comset CX displays. The latter allows occupants to raise or lower the temperature within pre-defined limits and check room temperature and status.

Additionally, each office also offers occupancy detection. When an office is unoccupied for a preset time, the lights switch off and the heating/cooling reverts to a stand-by setting.

"There are no conventional boilers or electric heaters anywhere on site," says Mr Grant. "The Priva BMS is juggling the various valves and other plant to make maximum use of available heat and direct it accordingly." There is also a heatpump to produce additional heat if required, or cooling in the summer for the offices and amenity areas. So far, the heat pump has never been called on to provide heat.

The project at JZ Flowers has a supervising PC running Priva TC Vision for onsite and remote control, and Priva TC History, which retrieves selected logged data online and saves it to an open database. Extensive use of the graphics features of TC Vision enable operators to easily visualize the state of all plant and the environment in the facility with just a couple of mouse clicks. The Priva system also has an email messaging service for the JZ Flowers maintenance team, and Cambridge HOK.

"The previous facility of JZ Flowers was pretty old-school to be honest," says Mr Grant. "It relied on conventional technology such as thermostats and manual light switches - quite inefficient. Now, however, they effectively have no heating bill for the production area or offices because it all uses recycled waste heat."

Such is the rate of expansion at JZ Flowers that the company is already planning its next phase of growth, a strategy that will incorporate the build of another facility immediately adjacent to the present one. So pleased is JZ Flowers with its existing pack-house that the contract for the next one didn't even go out to tender: Cambridge HOK and Priva have already started work!