Connecting SMEs for a green economy

Heat from Cow's Milk

wytzegaast's picture

The solution uses residual heat from cooling cow's milk for heating a residential dwelling.

The aim of the solution is to use an existing technology of converting residual heat into hot water for heating a house. The heat is a residual product of a cooling process to bring the temperature of cow's milk from 37 degrees to 4 degrees Celsius. Beforehand, this heat was ventilated into the air. The technology is applied on a farm in Tjerkgaast (the Netherlands) and co-developed and installed by the company Bijlsma.

The solution contributes to a more efficient farming process as follows:
- it uses residual heat for heating the living area of the form or, otherwise, a residential dwelling.
- the heat is also used for warming of water from the tap.
- during the summer, when heat demand is low, the system is reversed and cold water is used to pre-cool the milk

The advantage of the process is that energy consumption can largely be met with residual heat, which reduces the need for combusting natural gas or oil.

The process is relatively simple. Inside the system for cooling the milk, a heat exchanger is placed with a tubes system through which water flows. The heat from the cooler warms the water which is then transported to the living area of the farm (through the floors), to heat the house and warm the tap water. During the summer, the same water tubes are used to pump cold water through the cooler which contributes to the cooling process of the milk, which reduces the need for the compresser in the cooler to operate. The water that leaves the cooler can be given to the cows to drink.

The company Bijlsma co-developed the technology together with the technology supplier. In addition, collaboration was established with a farmer in the village to apply the technology.

The elegance of the solution is that is uses a relatively well-known technology (heat exchanger) to capture residual heat in a farming environment.

Further details

How was the green solution financed?: 
Would you characterize the green solution as: 
Medium to low capital intensive investment (i.e. €3,000 -€10,000)
Operating and maintenance costs: 
Yes, low O&M costs
Technical and capacity requirements?: 

Knowledge of combining cooling compressors and heat exchangers is prerequisite.