Energy Systems for Swine Production
The West Central Research and Outreach Center (WCROC) farm site includes facilities for swine production that follow conventional norms for nurseries, farrowing and finishing, as well as facilities for investigating alternative methods of housing pigs. Energy use for swine production includes building heating and ventilation, electric loads (lights, augers, etc.), pressure washers and fuel for vehicles. These direct (fossil fuel) energies come primarily from propane and electricity.
The existing swine facilities at the WCROC can be used to model and demonstrate potential energy-efficient retrofits. Our strategy is to convert all energy loads to electricity and make these loads as small as possible with efficiency upgrades. Eventually, on-site renewable electric generation could supply some or all of the electric load thus allowing the building to approach net-zero (producing as much energy as is used).
The conventional confinement swine system is similar to many smaller swine farms in size and in utilizing a combination of modern and older facilities. We are developing baseline energy consumption information for our swine facilities so that potential energy-optimized systems can be demonstrated and evaluated. Energy-optimized systems include converting existing energy loads to electricity, implementing energy efficiency measures, and adding renewable electric generation. This process is detailed in the production chart (PDF).
Greening of Ag: Improving Energy Use
As part of our Greening of Ag Initiative, which began in 2014, we have installed solar panels on one of our finishing barns. Our goal is to model and demonstrate potential energy-efficient retrofits in order to reduce the amount of energy used in swine production.
In order to achieve this, we've taken the following steps:
- Conduct energy monitoring of electrical, LP gas, diesel, and water usage throughout 2014-2015 to determine baseline use.
- Perform life cycle analysis on the various stages of pork production with the goal of developing more efficient and economical energy systems.
- Partner with six commercial pork producers that are characteristic of production systems in Minnesota. Monitor their energy usage to establish baseline use.
- Installation of a 27 kW solar PV system on the roof of the WCROC finishing barn. The system was interconnected to the utility grid in June, 2015 (figure 1). We estimate the system should produce about 36,000 kWh of electricity per year.
Funding for this project is provided by the U of MN Rapid Agricultural Response Fund.
Sow Cooling and Piglet Heating
Pork producers need innovative housing systems that help address environmental and energy concerns while remaining competitive in the global market. Sows and piglets have distinctly different thermal comfort zones which need to be accommodated while lowering the carbon footprint of swine production. On-farm energy auditing determined heat lamps are the largest electric load in breed-to-wean swine facilities. An electric heat pump system was designed to cool sows and provide heat for piglets via in-floor heat exchangers and is powered by a 20 kW solar PV array. The system replaces heat lamps and will hopefully improve sow performance while reducing overall energy usage.
- Sow Cooling and Piglet Heating (video - YouTube)
- WCROC Swine Barn Solar PV System handout (PDF)
- WCROC Farrowing Barn Heating and Cooling System (PDF)
- Lactating Sow Performance with Solar-Powered Cooling (PDF)
- Using Solar Energy to Cool Sows (video presentation - YouTube)
- Study goes to pig barns to find actual energy use (National Hog Farmer)
- How efficient is a solar barn? (Successful Farming)
- Another way to save energy is to use a Reduced Nocturnal Temperature (RNT) regimen. Recent studies conducted across the Upper Midwest suggest consumption of heating fuel and electricity can be reduced 29 percent and 19 percent, respectively, in swine nurseries with no detrimental effects on pig performance (Johnston et al., 2012). This temperature-management approach could be implemented in other phases of production. Lowering Energy Consumption by Reduction of Temperature in Swine Facilities
- Energy Usage in Swine Production Systems