Next Generation Energy is managed and written entirely by Seed editors and expert guest bloggers. Read more about them As with any industry, energy use is a big part of the bottom line for farmers. Practices aimed at reducing on farm energy cost also provide the obvious benefit of reducing green house gas (GHG) emission as well. Another key contributor to global warming from farms is N2O, a particularly noxious GHG with climate change effects many times greater than CO2. According to the Stern Review on the Economics of Climate Change, agriculture is responsible for the most GHGs second only to the power sector, see the Annex sections for data.
The USDA Natural Resource Energy Conservation Service has created the Energy Consumption Awareness Tools. The end point is meant to elucidate areas a farmer can focus to reduce energy consumption. In principal, several of these areas are not much different from those of non-farmers. Many of them boil down to driving less. Land management, planting, application of fertilizer and pesticides, and harvesting all requires driving farm machinery in the field. I am not aware of efforts to increase farm vehicle efficiency, so please share if you do. On the other hand, reducing driving is a very active area of research, outreach and practice. Other arenas are the simple practice of increasing efficiency of on farm facilities and their utilities.
As highlighted by the USDA, key conservation practices include:
Crop Residue Management--According to the Conservation Technology Information Center, a farmer can save at least 3.5 gallons of fuel per acre by going from conventional tillage methods to no-till, a conservation practice that leaves the soil undisturbed from harvest through planting except for narrow strips that cause minimal soil disturbance. At November 2005 diesel prices, this amounts to $7.70 per acre in production cost savings. On a farm with 1,000 acres of cropland, these savings add up to 3,500 gallons of diesel fuel per year valued at $7,700.
Nutrient Management--The proper collection, handling, storage and application of manure help to protect our nation's waters and provide a significant nutrient source for crop production. Currently, about 2.7 million tons of manure-based nitrogen are applied on agricultural land. It takes approximately 40,000 cubic feet of natural gas to produce a ton of commercial nitrogen fertilizer. Doubling the application of manure-based nitrogen could save agriculture approximately $1.2 billion worth of natural gas each year. Substituting manure for commercial fertilizer can reduce fertilizer costs as much as $85 per acre for a 1,000-acre farm.
Irrigation Water Management-- The 2003 Farm and Ranch Irrigation Survey reports approximately 27 million U.S. acres under sprinkler irrigation. About 80 percent of these acres utilize center pivot systems. If the acres under medium pressure were converted to low pressure, the per acre energy savings could be about $9.00 per acre. The conversion of the high-pressure systems to low pressure would result in additional savings of $41 per acre. Diesel powered pumps are used on about 10 million irrigated acres. A 10 percent improvement in water use efficiency could reduce diesel consumption by 8 gallons per acre.
Precision Agriculture--By reducing overlap in fertilizer and pesticide applications on the 250 million acres of cropland used to produce major crops, petroleum-based fertilizer and pesticide costs could be reduced up to $1 billion annually. A 1,000-acre farm can save up to $13 per acre by using precision agriculture techniques.
Pesticide Management--Pesticide production depends heavily on energy resources. Integrated Pest Management reduces energy use and environmental risk while maintaining product quality. For example, some cherry producers have abandoned traditional spraying schedules to spray based on in-the-field microclimate information obtained from monitoring equipment and scouting. This can reduce the typical herbicide cost about $40 per acre with a 25 percent reduction of herbicide application.
Prescribed Grazing Systems-- it takes 40 pounds of nitrogen (high natural gas user) at $0.40 per pound to produce a ton of grass hay; 1.35 gallons of diesel fuel at $2.41 per gallon to raise, harvest, store, and feed the hay; and dry matter losses of about 30 percent for field-stored hay, every month that cows can remain on pasture reduces direct energy costs by about $10.70 per cow.
Windbreaks and Shelterbelts--Windbreaks and shelterbelts can reduce wind-induced erosion and save heating and cooling costs associated with farmsteads. When properly placed to shield farm buildings from strong winds, windbreaks can lower heating and cooling costs by up to 20 percent.
Interest and improvements in on-farm energy efficiency has been and will continue to be a particularly fertile (pun intended) space. One sector not discussed here (perhaps another post) is crop improvement and genetic engineering. New varieties of crops with improved water use and nutrient use efficiencies will require fewer inputs. The implementation of improved farming practices as well as biotechnology are critically important avenues towards increased energy efficiency and reduction of GHG emission.
Comments
This article says that tractor fuel efficiency has been improving by around 1.5% per year since 1975. I'd expect similar improvements in other farm machinery since the engines would often be the same as tractor engines.
I was surprised agriculture's emissions were that high, until I read the annex and realized they included things like methane release from rice paddies and NO2 from fertilizer applications. And CO2 is significant from fuel use, crop residue burning and management practices that degrade soil organic matter.
I recall reading that precision agriculture (GPS guidance and autosteer) is the most rapidly adopted new technology in agriculture _ever_. Farmers are not necessarily reactionary conservatives, some of the other changes listed might not be as obvious a benefit to the farmer's bottom line - farming is a business and change has to be profitable if it is to be widely adopted. In my area of Manitoba zero tillage is uncommon because of the local climate, but 'recreational tillage' and summerfallow have become rarities too.
I don't see any easy substitutes for liquid hydrocarbons in agriculture any time soon. Horsepower is needed out in the fields and the only way to get it there is in a fuel tank.
Posted by: Brad | October 5, 2008 11:34 PM
Your Nutrient Management section needs more work. Large grain farms do not necessarily have access to large amounts of manure freely given or bought. There is the cost of delivery and application. There is also the problem in the amount of available nitrogen in manures. Like most "natural" things, quantities and quality varies greatly between sources. Not to mention the noxious gases released by raw manure. It all seems a little impractical to me.
I think that farmers, as businessmen, would be most amenable to many of these changes. To get beyond their innate stubbornness (a necessary trait for a class of people who have to deal with uncertainty on a daily basis), you concentrate on what it will save THEM personally. DON'T mention AGW, DON'T talk about saving the planet, DO talk about saving them $10.00/acre..... Do talk about the positive National Security implications of becoming energy independent.
Posted by: Oldfart | October 6, 2008 9:42 AM
thanks you
Posted by: chat | January 22, 2009 11:47 AM