The results of a study of heat recovery and conversion from cowshed ventilation air

The heat obtained and converted from cowshed ventilation air was studied using an installation for heat recovery composed of a 3 kW fan coil unit with an output of 100 m3 ∙ h-1 and heat pumps with a capacity of 8 kW. The heat amounting to 0.346 GJ · day-1 was used to heat water in a 200dm3 buffer tank. Energy inputs averaged 47.34 kWh per day, and the efficiency index during the period was COP = 2.005. Measurements were performed from August to October and data from the heat meter and the thermometer were read at the same time every day. To increase the installation's efficiency (COP), it is necessary to increase the removal of heat. This is possible by means of additional heaters or a boiler for hot water, and by reducing the performance of the fan coil's circulation pump and decreasing the fluid flow rate to 0.3 m ∙ h-1 .