Retrofitting of a pig nursery with solar heating system to evaluate its ability to save energy and reduce environmental pollution

Abstract

The objective of the present experiment was to evaluate the efficiency of an active solar space heating system to save energy and reduce the emission of CO2. The system was installed in an experimental nursery pig building and consisted of evacuated tube collectors (south-facing), hot water tank, regulatory pump and copper pipes mounted on the side wall to distribute heat inside the house. The efficiency and output of the collector was calculated using the ambient temperature, collector temperature and solar radiation. The average efficiency of the evacuated tube collector was 64.8% and its calorific contribution was 125 kWh/m2/day. The internal temperature and humidity, pig performance, energy use, CO2 emission and cost were compared to an identical, adjacent conventional house. Internal temperature and humidity were comparable in both houses, except that the bottom temperature in the center and back of the solar house was higher than in the conventional house. Piglets in the solar house had a slightly higher body weight and lower feed intake than those in the conventional house. The electricity use in the solar house was reduced by 15% (261 kWh) relative to the conventional house. The reduction in electricity use reduced the CO2 emission by 15% (128 kg) relative to the conventional house. Overall, the results of this study indicate that active solar heating systems can successfully reduce energy use and CO2 emission. Consequently, future studies should be conducted to evaluate other green house gas emissions and the costs associated with use of the developed solar system.