Cover Image: January 2012 Scientific American Magazine See Inside

How to Make the Food System More Energy Efficient

Changes in agriculture, policy and personal behaviors can reduce the energy a nation uses to feed itself and the greenhouse gases it emits















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Another waste stream that can save food energy is carbon dioxide from smokestacks at coal plants. It can be used to grow algae for human food, animal feed and fuel, thereby avoiding some traditional energy inputs for agricultural production. Some people already eat algae directly for nutritional reasons, and some national restaurant chains use them as a stiffening ingredient. Algal lipids can also be converted into biodiesel, providing a low-carbon, domestic, renewable fuel that is made from something other than food-based feedstock. The remainder of the algal biomass is typically made up of proteins and carbohydrates, which might displace corn-based feed for animals, making more corn available for food and thereby contributing positively to the food-energy nexus. Some algae grow well in brackish water or saltwater, too, eliminating demand for freshwater. Private industry (through a variety of start-ups such as Solazyme), national labs such as the National Renewable Energy Laboratory, and universities such as the University of Texas at Austin and the University of California, San Diego, all have active testing and pilot programs. Although algal solutions seem to be decades away from large-scale implementation, their promise warrants additional research, so policy makers should continue funding development.

More Crop per Drop
Simply implementing innovative agricultural techniques that have already been perfected in pilot programs on a much wider scale could significantly reduce the 10:1 energy-food ratio. For example, drip irrigation provides more crop per drop, sparing freshwater and the energy needed to pump it. The conventional approach—the center-pivot sprinklers that create alienlike green crop circles in the middle of brown deserts (easily visible when flying overhead)—is extremely wasteful, spraying water into the air where a major fraction evaporates. Droplets that do land on crops are likely to hit the leaves and stalks instead of the roots, causing more evaporation loss. In a typical drip-irrigation setup, long sections of narrow tubing laid at the bottom of plants sown in a row deliver water directly to the roots.  Researchers at Iowa State University estimate that corn farmers in that state would use 40 percent less water and lower their energy bills by 15 percent with drip irrigation. Half a dozen large farm suppliers now offer the systems, which, if used widely, could save thousands of megawatt-hours of electricity nationwide every year. Incentives to switch to drip irrigation, combined with penalties for wasted water, might hasten adoption.

No-till agriculture is another promising approach. It reduces the disturbance of soils by using special planting equipment that places seeds into untilled soil through narrow surface slots rather than the blunt approach of turning the soil. Disturbing the soil less reduces labor, irrigation, energy, erosion and carbon emissions. Argentina is the world leader; more than half the farms there deploy this advanced technique. Training for farmers about the advantages of no-till can be implemented through agricultural extension services nationwide.

Laser-leveled fields can minimize erosion, irrigation and fertilizer runoff. Most fields have a gradual slope, which causes unequal water distribution and uneven collection of runoff. Rather than risking one portion getting less water than it needs, farmers often overfill the entire field, with the excess spilling over into local waterways. By making fields level, farmers waste less energy pumping water, and less fertilizer is needed because less runs off.

The advent of GPS-enabled tractors, combines and other machinery—today a standard feature offered by manufacturers such as John Deere—has introduced the concept of “precision farming,” which drives up productivity and drives down energy use. GPS guidance allows farmers to tend fields and plant crops literally to the inch, reducing wasted space, time and fuel, without even needing to steer machines with their hands. Although the upgrades for a moderately sized farm might cost $10,000, researchers at Purdue University have shown that the benefits outweigh the cost. For one thing, fuel use decreases. Incorporating GPS with field diagnostics allows farmers to map out soil conditions and fine-tune the application of chemicals, which can vary from one end of a field to the other, ultimately requiring less. Fields can also be worked at night and during fog and rain, when human visibility is limited, pushing productivity up.



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  1. 1. gesimsek 02:24 PM 12/20/11

    Let's not forget the amount of energy we use to transport the foodstuff

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  2. 2. David N'Gog in reply to gesimsek 11:13 AM 12/29/11


    That would be "distribution" which is mentioned.

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  3. 3. ssarryo 10:21 PM 12/29/11

    I think that people should start growing some crops at home or other places like a community garden, a window sill, etc. I started planting some tomatoes, onions, cilantro, and jalapeno's to make salsa.

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  4. 4. JerryWood 12:16 PM 12/31/11

    Beating The Drum of Popularism; Change what was learned for large population to reach older age: The most efficient answer will focus to absorption of nutrients. How to better use a food, so less quantity is used and more of the food does not go to waste. Sample: IGF1, found naturally in Milk & Honey helps with the absorption of amino acids. If, Billy takes a Colustrum capsule with his meat. The affect: Billy should eat less meat at dinner. Hence, less Cattle need to be raised to satisfy Billy's hunger. Or more Cattle can now be exported to satisfy the growing world population, with more people reaching older age. However, more research needs to be started on increasing the absorption of amino acids and a scale to measure absorption by.

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  5. 5. JerryWood in reply to JerryWood 02:50 PM 1/14/12

    Discovery of Plant 'Nourishing Gene' Brings Hope for Increased Crop Seed Yield and Food Security; This artilce underlines plants and increasing nutrients. Again, more research is need, when a Person consumes food, to increase absorption of nutrients.

    http://www.sciencedaily.com/releases/2012/01/120113102054.htm

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  6. 6. krishna13061991 09:49 AM 2/2/12

    In my environs, in India, the major way to reduce food-energy consumption is to focus on innovative storage and distribution chains, minimizing wastage.
    In India, meat consumption is very less compared to U.S or any other developed economy. And hence, reduced efficiency due to meat production does not occur here. However, as may be noted from the unfortunate turn of events happened over last year, our government godowns (where food stock is stored for distribution) prefer rotting of the same, to, distribution among the poor.
    An important factor that is overlooked in this discussion is the unnecessary hype that surrounds any imported food product compared to native version of the same. These imports lead to wastage of hundreds of tons of fuel. A good example is, how India imports apples from all around the globe, when they can be raised in substantial amount in Shimla. Ironically, apple from Shimla are again exported to other nations.

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  7. 7. krishna13061991 in reply to ssarryo 09:52 AM 2/2/12

    That is a great idea. That even leads to developing an innate sense of belongingness with the nature as well as the community.

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