At one point in your life, you have probably been told to “turn off the lights” or “close the door.” Ultimately, the person footing the bills was trying to save money. But there is also an environmental benefit to saving energy, especially when our energy comes from burning coal and natural gas (fossil fuels). So, when it comes to sustainable agriculture, energy conservation and energy efficiency are critical.
Energy conservation refers to the reduction in total energy consumed, and energy efficiency pertains to the amount of work or yield per unit of energy consumed. For example, most of us use gasoline in our vehicles. In this case, efficiency refers to the number of miles the car drives per gallon of fuel consumed. Conservation would directly equate to the total amount of fuel saved. So, what options do farmers have for reducing energy consumption, increasing energy efficiency, and incorporating renewable energy sources on the farm?
Over the past 25 years, most farms have increased their energy efficiency with improvements to equipment maintenance, by changing agricultural practices, and through technology and equipment investments. For instance, newer grain drying systems consume less energy with lower drying costs. Adopting reduced tillage, cover crops, and crop rotations reduce energy consumption. A large portion of energy costs in row-crop agriculture comes from fertilizer, pesticides, and other agricultural inputs. Following nutrient management plans, pulling soil samples, and incorporating precision agriculture can reduce energy inputs by more efficiently using fertilizers (Right Source, Right Rate, Right Timing, Right Placement).
The Extension Foundation has created a comprehensive suite of online fact sheets, case studies, decision tools, and worksheets to address farm energy conservation and efficiency. Topics cover everything from lighting efficiency to building insulation to tractor maintenance, and more. There is a lot that can be accomplished on the farm for energy conservation and efficiency.
As of now, renewable energy is nowhere close to replacing traditional fuels on the farm. However, incorporating solar, wind, geothermal, and biomass energy production and use can offset energy use from fossil fuels, and potentially become a revenue source for farmers too.
Solar energy can be used for heating greenhouses and water, and solar energy can be converted into electrical energy using solar panels (photovoltaics). Solar panels are becoming more cost-effective and used more commonly for lighting, electric fencing, motors, fans, water pumps, and battery charging. Prior to the construction of renewable energy resources, be sure to check on local zoning ordinances along with state and national rebate or incentive programs. In many cases, “net metering” can be implemented to track incoming and outgoing electricity, allowing farmers to earn money for excess solar energy that is fed back to the electrical grid.
Wind can be harvested through wind turbines to generate electricity, but requires average annual wind speeds in excess of 10 miles per hour. Farmers across Indiana have contracted land to wind companies, bringing additional dollars back to the farm.
Drone imagery of wind turbines in Tipton County, Indiana. (Photo Credit: Austin Pearson)
Geothermal energy can be used to heat and cool buildings and homes using heat pumps that take advantage of stable ground temperatures deep in the earth. These systems are notably more expensive than natural gas and/or propane systems for regulating building temperatures, but the energy efficiency is much higher. Biomass energy involves plant and animal materials that either pull oils and sugars from plants to fuel vehicles (biofuels) or the burning of biomass (biopower). Biodigesters employ microorganisms to decompose biomass (most commonly livestock manure) and produce biogas, which can generate cleaner fuel for engines, electricity production, air and water heating, and refrigeration. Additional renewable energy resources can be found on the Extension Foundation’s Farm Energy resource page.
Farming for a Better Climate is written in collaboration by the Purdue Extension, the Indiana State Climate Office, and the Purdue Climate Change Research Center. If you have questions about this series, please contact in-sco@purdue.edu.
