DURBAN, SOUTH AFRICA and ROME, ITALY — The global food system needs to reduce its dependence on fossil fuels to succeed in feeding a growing world population, the United Nation’s Food and Agricultural Organization (FAO) said on Nov. 29.

"There is justifiable concern that the current dependence of the food sector on fossil fuels may limit the sector's ability to meet global food demands. The challenge is to decouple food prices from fluctuating and rising fossil fuel prices," according to an FAO paper published during the UN Conference on Climate Change.

High and fluctuating prices of fossil fuels and doubts regarding their future availability mean that agri-food systems need to shift to an "energy-smart" model, according to the report Energy-Smart Food for People and Climate.

The food sector both requires energy and can produce energy — an energy-smart approach to agriculture offers a way to take better advantage of this dual relationship between energy and food, it says.

The food sector (including input manufacturing, production, processing, transportation marketing and consumption) accounts for around 95 exa-Joules (1018 Joules), according to the report — approximately 30% of global energy consumption — and produces over 20% of global greenhouse gas emissions.

On-farm direct energy use amounts to around 6 exa-Joules per year, if human and animal power are excluded — just over half of that is in OECD countries.

On farms, energy is used for pumping water, housing livestock, cultivating and harvesting crops, heating protected crops, and drying and storage. After harvest, it is used in processing, packaging, storing, transportation and consumption.

"The global food sector needs to learn how to use energy more wisely. At each stage of the food supply chain, current practices can be adapted to become less energy intensive," said FAO Assistant Director-General for Environment and Natural Resources Alexander Mueller.

Such efficiency gains can often come from modifying at no or little cost existing farming and processing practices, he added.

Steps that can be taken at the farm level include the use of more fuel efficient engines, the use of compost and precision fertilizers, irrigation monitoring and targeted water delivery, adoption of no-till farming practices and the use of less-input-dependent crop varieties and animal breeds.

After food has been harvested, improved transportation and infrastructure, better insulation of food storage facilities, reductions in packaging and food waste and more efficient cooking devices offer the possibility of additionally reducing energy use in the food sector.

Adding up both on-farm and post-harvest losses, around one-third of all food produced — and the energy that is embedded in it — is lost or wasted, FAO's report notes.

FAO's report also highlights the tremendous potential for agriculture to produce more of the energy needed to feed the planet and help rural development.

"Using local renewable energy resources along the entire food chain can help improve energy access, diversify farm and food processing revenues, avoid disposal of waste products, reduce dependence on fossil fuels and greenhouse gas emissions, and help achieve sustainable development goals," it says.

Where good solar, wind, hydro, geothermal or biomass energy resources exist, they can be used as a substitute for fossil fuels in farming and aquaculture operations. They can also be used in food storage and processing. For example, sugar mills frequently use their residue materials for combined heat and power generation. So-called "wet processing wastes" like tomato rejects and skins, or pulp from juice processing, can be used in anaerobic digester plants to produce biogas. Already, millions of small-scale domestic digesters are being used by subsistence farmers in the development world to produce biogas for home use.

Significant action is needed to reduce food losses, and this will also improve energy efficiency in the agri-food chain.

Finally it is essential to improve access to modern energy services to the millions of people who still use biomass in a nontraditional way as energy for cooking and heating.

Transitioning to an energy-smart agricultural sector will be a "huge undertaking" that will require long-term thinking, and needs to start now, FAO said.