SARE Grant Recipients Explore Alternative Energy Practices
The story below features SARE grant recipients turning to alternative energy practices-despite the steep learning curve often involved.
Source: AgriView, Jane Fyksen, Crops Editor
High energy prices aren't going to go away. Concerned about the impact energy costs will have on the long-term sustainability of their operations, more producers are turning to alternative energy practices-despite the steep learning curve often involved.
While energy-efficiency measures are generally the fastest and cheapest way to reduce energy-related costs, many farmers are now turning to their land and operations to generate renewable energy. Corn ethanol has long nabbed the spotlight, but energy experts with the Sustainable Agriculture Research and Education initiative (SARE) say other renewable types of energy, such as solar, wind and fuels from animal waste or other energy crops, also offer opportunities to increase energy self-sufficiency on the farm.
"As an added bonus, these energy sources can generate extra income through sales of surplus and offer a more sustainable alternative to energy-intensive corn," SARE specialists point out. SARE's mission is to advance innovations that improve profitability, stewardship and quality of life by investing in groundbreaking on-farm research and education.
There's a new resource that can serve as a starting point in farmers' exploration of energy alternatives. "Clean Energy Farming: Cutting Costs, Improving Efficiencies, Harnessing Renewables" features innovative SARE-funded research and real-life examples of farmers who are improving energy efficiency and saving money.
With so many new technologies to choose from, it's tough to know where to start. Here's SARE's recommendations:
- Start simply and carefully: Conduct an energy audit (a vastly underutilized tool, according to SARE experts) and consider implementing efficiency measures like energy-efficient light bulbs, machinery upgrades and green building design;
- Determine your fuel use and demands and look for ways to cut back;
- Explore farming practices that conserve and build soil, save water and curb the release of greenhouse gases;
- Assess your natural energy resources: Do you have wind? Sun? Suitable land for biomass? Adequate manure reserves for biogas production?
- Take stock of your financial resources: Can you comfortably experiment?
- Talk to others about their clean energy practices.
Fifteen percent of agricultural production costs are energy related, according to the U.S. Department of Agriculture (USDA)-and as energy prices rise, these costs claim an ever-bigger portion of farm budgets. The quickest, cheapest way to lower these costs is by improving energy efficiency. Simple things, like keeping tractor tires properly inflated and engines tuned, can go a long way toward saving fuel. Clogged air and fuel filters and injectors burn more fuel, as do motors with rusty or corroded parts, worn bearings, loose belt drives and clogged condenser coils. Dirty fans can be up to 40 percent less efficient.
Replacing incandescent bulbs with fluorescents saves money far beyond the original investment. An energy audit on a Maryland poultry farm, for example, found that switching 40 and 60-watt incandescent bulbs to 5-watt cold cathode fluorescent bulbs required an initial outlay of $2,168, but would save $2,658 per year. Given the bulbs' five to eight-year life span, this farmer anticipated total savings of $11,000 to $18,000-from something as simple as replacing light bulbs.
Dairy farms' heavy reliance on electricity-mostly for collecting and cooling milk, heating water and lighting-provides many energy-conservation opportunities. The Massachusetts-based Center for Ecological Technology (CET), which received a SARE grant to implement energy conservation measures, conducted an audit for a dairy farmer, showing him how much he could save with a variable speed drive. Variable speed drives use sensors to adjust pump capacity to demand, thus doubling efficiency and lowering expenses 50 to 80 percent. They generally cost from $1,800 for a five-horsepower (3.7 kW) to $7,400 for a 30-horsepower (22.4 kW) unit. But the significant savings for this particular producer-as much as $4,750 per year-allowed for a quick payback, from six months to four years.
Plate coolers (simple heat exchangers that take the heat from warm milk and transfer it to cold well or pipe-water) are also excellent energy savers. According to Florida Cooperative Extension, plate coolers can save a 500-cow dairy farm as much as $2,000 per year in electricity costs or $750 in LP gas costs.
Efficient buildings save money and improve comfort. In the Missouri Ozarks, SARE grant recipient Nicola MacPherson wanted to take advantage of the busy fall market for her shitake mushrooms without using more fossil fuel than necessary. She built a 96-by-36-foot greenhouse "in-ground" to a depth of 3 to 4 feet in order to use the earth's natural moderating properties against temperature extremes. She didn't stop there. MacPherson heats her greenhouse by burning spent shitake logs in a wood furnace that pumps fluid into tubes beneath a slab radiant-heated floor. A trench down the floor's middle drains misting and irrigation water for the moisture-sensitive fungi and allows better side-to-side control of the heat.
Steven Schwen of Minnesota elevated efficient greenhouse design to an art form. He sited glazed windows to the south, and insulated the north side by building it against a small hill. He then harnessed the sun with a "thermal-banking" floor, which stores heat generated by the sun during the day to be released during the cold nights. He also installed a solar-powered variable speed fan, which helps blow hot air under the soil, heating it to germination-friendly temperatures. Schwen has been able to maintain steady temperatures to grow frost-tolerant crops, such as salad mix, braising greens and herbs. "In February, even if it's below zero, the greenhouse is in the mid-20s and the ground inside doesn't freeze," says Schwen. "Later in the month, when it's 10 degrees outside, we can take advantage of the sunny days and maintain a temperature differential of 40 degrees between the inside and outside."
Leonardo Busciglio in New York wanted the energy captured by the sun to do double duty. He took a tanker trailer and sliced it longitudinally in half to form a huge 4,000-gallon trough. (It should be noted that many types of tanker trailers, such as fuel and chemical, are not suitable for reuse. The tank, which must be big enough to keep the water from freezing, absorbs heat during the day and releases it back into the greenhouse at night. He also uses the tank to raise trout and tilapia. Busciglio discovered yet another benefit from the water tank; the ever-present humidity means his salad greens and watercress no longer need misting.
Busciglio, who used a SARE grant to add both solar and wind to his operation, operates a wood furnace about an hour per day during the coldest days to keep the water temperature optimal for the fish and, when necessary, to maintain temperatures in the greenhouse. He runs the fish waste through a bio-filter, which kills the algae, and then recycles the filtered water as plant fertilizer.
A significant portion of the energy used in agriculture comes from fertilizers, pesticides and other inputs that require significant energy to produce. Reducing the use of these materials, especially nitrogen fertilizer, is an effective way to cut back energy use on the farm. For example, substituting manure for a ton of nitrogen fertilizer saves 40,000 cubic feet of natural gas and can reduce fertilizer costs by $85 per acre.
Practices such as grazing livestock, decreasing tillage, cycling nutrients through manure and cover crops, and using rotations to control pests also reduce energy use while improving soil organic matter and decreasing soil erosion. Nutrient management plans, soil testing, banding fertilizers and pesticides, and precision agriculture similarly help reduce energy use.
Grazing systems can be good for the wallet, too. According to the Natural Resources Conservation Service (NRCS), producers can save about $11 per cow per month for each month the cow stays on pasture, thanks to reduced fertilizer and fuel costs.
Iowa State University animal scientist Mark Honeyman advocates "deep straw" systems for hogs as a cost and energy-saving measure. This system involves huts on pasture or deep bedding in hoop barns, or both. According to Honeyman, these systems are much less capital-intensive than confinement, and have several added efficiency benefits: Bedding compost inside the hoop structures provides natural heat; manure packs can be used as compost; and costly power fans for ventilating confinement buildings aren't needed with these smaller structures because window and door openings provide enough natural air flow.
According to USDA, switching from conventional tillage to no-till can save about 3.5 gallons of fuel per acre. No-till also means farmers can use smaller, more fuel-efficient tractors. Assuming diesel costs of $2 per gallon, a 70-horsepower tractor can run for about $6 per hour while a 150-horsepower tractor consumes slightly more than double that.
To read more about Schwen's NCR-SARE Farmer Rancher Grant project, click here to visit the MySARE online reporting site.
Check out these videos from Schwen's greenhouse: