Summary
Stegeman in Deventer, the Netherlands, produces various types of sausages and other meat products. Due to production expansion this process required an extra amount of cooling capacity. Therefore expansion of the electric compression cooling plant required a larger electricity supply from the public grid. Stegeman has chosen to install a gas engine with a generator, thus avoiding high costs for the expansion of the supply. The heat that is simultaneously developed drives an absorption-cooling machine (ACM). This specific ACM supplies cold at a level of -10°C by means of a water/glycol circuit. In general, ACM's deliver cold at a level of approximately 6°C due to the cooling medium used (water). This new machine uses a mixture of water and ammonia, where the ammonia functions as the coolant. This principle makes it possible to cool to subzero temperatures.
The use of absorption cooling is advised in a situation in which a lot of residual heat of a sufficient temperature level is available. The use of primary fuel just for generating heat does not normally save energy. However, in this case the costs avoided by expansion of the electricity supply and the cooling plant make this project cost-efficient. Depending on the efficiency of the conversion of primary fuel to electricity in the public grid, this configuration with combined heat/power (CHP) may save energy too.
Applications for this type of ACM can be found in the food and beverages industry as well as the (petro-) chemical industry.
Total project costs for Stegeman on behalf of the ACM have been estimated at NLG 725,000. Colibrie bv has been granted an additional research and development subsidy to develop this ACM. The energy savings amount to 900,000 kWh per annum with a financial value of approximately NLG 182,000. The payback period is therefore approximately 4 years in combination with the CHP-unit.