In a study on "energy-smart" food production, released ahead of next week's Rio+20 conference on sustainable development, the FAO warned that failure to change could leave people hungry.
"Higher costs of oil and natural gas, insecurity regarding the limited reserves of these non-renewable resources, and the global consensus on the need to reduce greenhouse gas emissions could hamper global efforts to meet the growing demand for food, unless the agrifood chain is decoupled from fossil-fuel use," the report says.
Global food production - from farms to the processing and marketing chain - consumes 30 percent of all available energy, according to the FAO study. Of that consumption, 70 percent happens after food leaves farms, when it is transported, processed, packed, shipped, stored, marketed and prepared.
The report notes that about 40 percent of all energy used in the food chain is lost, with around one third of all food, or around 1.3 billion tonnes, thrown away due to spoilage and waste each year.
"There are huge opportunities to improve energy efficiency in the food chain, as well as to produce sustainable energy within agriculture - these opportunities must be boldly explored, and I hope to see them figure prominently in discussions at Rio+20," FAO Director-General José Graziano da Silva said in a statement.
ADAPTING FOOD SUPPLY CHAIN
At each stage of the food supply chain, practices can be adapted to become less energy-intensive, the FAO paper says.
Changing how land is prepared for crops can cut the amount of energy used on farms, along with more fuel-efficient engines, less reliance on non-organic fertilisers and pesticides, and a shift to crop varieties and animal breeds that require fewer inputs.
Beyond the farm gate, there is great scope for improving food transportation, insulating storage facilities better, cutting down on packaging, reducing food waste and cooking more efficiently, the FAO says.
The use of renewable energy - solar, wind, mini-hydro and bioenergy - in farming systems and villages can boost agriculture and rural livelihoods. And animal waste and other organic by-products of farming and food production can be used to generate energy such as bio-gas, the report says.
It also highlights how nearly 3 billion people have limited access to modern energy services for heating and cooking, and 1.4 billion have zero or limited access to electricity.
As a result, they have little chance of achieving food security, and no opportunities for securing productive livelihoods that can lift them out of poverty, the report says.
"Feeding a growing world population will require a 60-percent increase in food production by 2050, but we are not going to be able to meet that goal the way we did during the Green Revolution, relying on fossil fuels," said Alexander Müller, FAO's assistant director-general for natural resources and the environment. "A very different approach is required."
The organisation has launched an "Energy-Smart Food for People and Climate (ESF) Programme", aiming to help member countries make their food production systems more energy-efficient, diversify into renewable energy, and improve energy access and food security through integrated production of food and energy.
(Editing by Rebekah Curtis)