Cooling and heat in one plant
Milk chilling and cold storage reject heat while pasteurisation and cleaning require it. This coincidence can support direct recovery or a heat pump, subject to temperatures and schedules.
Separate base and peak demand
Daily cleaning can create short hot-water peaks. A heat pump may cover the steady requirement and charge a tank between cycles while a boiler remains available for peaks or higher temperatures.
Measure the refrigeration side
Condensing conditions, compressor sequencing and seasonal cooling load determine recoverable heat. The design must not increase refrigeration energy merely to create a warmer source.
Quantify cooling and cleaning together
Milk cooling, chilled storage and process refrigeration reject heat while pasteurisation preparation and clean-in-place systems consume it. Log both sides on the same timeline. The useful source is condenser heat available during the hot-water demand, not the refrigeration plant's nameplate capacity.
Condenser heat includes the cooling duty and compressor input, but it is not all available at one temperature. Desuperheating may provide a smaller high-temperature stream while the main condenser offers more heat at a lower level. Compare direct recovery with an upgrading heat pump before changing refrigeration pressure.
Design around hygiene and resilience
Cleaning temperatures, holding times and water quality remain production requirements. A heat pump may charge storage steadily and leave boilers to cover sterilisation peaks, startup or outages. That hybrid boundary should be explicit in the annual energy balance.
Request performance at the coldest expected source and hottest required sink, including pumps and intermediate loops. A dairy case study is relevant only when its temperatures, schedules and measurement boundary resemble the proposed duty.
Sources
General technical explanation. No specific external source claims are made on this page.