Performance Analysis of a Wind-Assisted Heat Pump for a Dairy

Abstract

ABSTRACT COMPUTER simulations based on measured component characteristics and site wind data predict the performance of a wind-assisted heat pump for a dairy. Farm residence space heating, water heating, and milk cooling are considered. A vertical axis Pinson C2E3 Cycloturbine is mechanically connected to a Carrier 5F30, 3-cylinder compressor with external cylinder loading/unloading capability. An electric motor powers the compressor during low wind conditions. Step-wise cylinder loading or unloading is used to load match the compressor with the cycloturbine torque at varying wind velocities. An insulated hot water reservoir and an ice-bank refrigeration milk cooler provide reserve energies. Simulation inputs include: (a) measured performance characteristics of the Pinson Cycloturbine and the Carrier compressor, (b) residential space heating and hot water requirements, (c) water heating and milk cooling requirements for a 50-cow dairy, and (d) nine months of one-minute interval wind velocity data from the wind turbine test site near Harford, NY. A description of the system and simulation results including dynamic effects are presented. System simulation results show a 41.6% reduction in the total electrical energy used for domestic heating, water heating, and milk cooling. However a major portion of this reduction was contributed by the heat pump since the wind turbine only provided an equivalent of 7.1% of the total energy used to drive the compressor on the heat pump.