The United Nations projects a world population of 9.7 billion by 2050. As a result, the world will have to feed 2.5 billion more people than today. The United Nations Food and Agriculture Organization estimates that by 2050 current food production needs to rise by 70 percent to satisfy the expanding demand. Given the planetary boundaries, especially limited energy and water resources, meeting this target is one of the century’s biggest challenges. At the same time, increased demand for processed food, meat, dairy, and fish adds further pressure to the food supply system, and growing impacts of climate change pose a further constraint.
The following article aims to provide a basic knowledge on the Energy-Agriculture Nexus. Check out the introduction video on the Energy-Agriculture Nexus by the partners of the "Powering Agriculture: An Energy Grand Challenge for Development" (PAEGC) initiative:
Further information on the mentioned MOOC on "Powering Agriculture - Sustainable Energy for Food" and related materials you can find here.
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The Energy-Agriculture Challenge
The Water-Energy-Food Nexus
The interdependency of water, energy and food is of concern. Food production requires water and energy throughout the agri-food sector. Energy production requires water and a substantial amount of biomass which needs to be produced using soils, water and nutrients. About 30 percent of global energy usage can be traced back to the food sector. This includes supply industry, agricultural production, processing, transport, merchandising and consumption. Agricultural primary production alone accounts for 20 percent, along with food processing (including transport) amounting to 40 percent. The agricultural and food sector thus contributes significantly to global energy consumption along the agricultural value chains. Further, Agriculture is currently the number one consumer of water resources, accounting for 70 percent of all freshwater use. Water is required for food production, processing, transport and preparation. Energy production processes use another 15 percent of global freshwater withdrawals. Energy, on the other hand, is a basic requirement for the withdrawal / pumping, distribution and treatment of water.
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Population Growth and Food Production
In the 1960s, the ‘green revolution’ offset the looming food disaster. Its success was based on improved plant breeding, intensification due to irrigation, increasing usage of inorganic fertilizer and energy inputs along the food chain. From farm mechanization, chemical fertilizers and pesticides to processing, cooling and packaging, fossil fuels made a significant contribution to this success. Such resources will not be available at cheap prices forever – all the more reason to start looking for alternatives. As the human population continues to grow, so does the demand for food.
However, a simple repetition of the green revolution to meet the increasing demand is highly unlikely. Fossil fuels are being increasingly exploited. This is happening at the cost of increasing greenhouse gases in the atmosphere. In addition, the continuing dependency on fossil fuels in the agri-food sector creates a high risk of fluctuating prices, potentially making food unaffordable for the economically weak – at least temporarily. The supply of fertile arable land is finite and therefore increased demand for food also puts pressure on the planet’s limited resource base. To identify effective changes, stakeholders will have to look at different aspects and segments along the agri-food value chains. For instance, approximately 40 percent of the global land area is classified as agricultural land with very limited opportunities for expansion. The FAO estimates that globally every year 25,000 million tonnes of topsoil are washed away by water erosion. Not only is the area available for food production limited but its suitability for production is being continuously eroded. There is an urgent need for solutions. Cultivation methods that make efficient use of resources are a major step forward.
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Agricultural Production and Value Chains
One conclusion to draw from the above analysis is that the agrifood sector must become more efficient to feed more people. This can be achieved either through energy efficiency measures or through the application of renewable energy. In any case, changes need to include the entire agricultural value chain as shown in Figure 1. This includes: the input provider, the farmers, the processors, the packagers, the distributors and retailers. Efficiency gains can be made in agricultural processing by decreasing energy input and use, as well as by reducing food losses before, during and after processing. In sub-Saharan Africa alone, 20 percent of harvests are lost, which comes at an annual cost of US $4bn . Losses often occur due to nonexistent, inadequate and/or interrupted energy inputs during storage or transportation and in markets.
Figure 1: Agricultural Value Chains (Sims et al., 2015)
However, reducing waste is not only a matter of energy: reducing waste is first and foremost about behaviour. By joining forces, civil society, private sector and government in high-GDP countries can reduce waste in the retail and consumption sector.
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The relationship between agriculture and climate change is twofold – agriculture is a contributor to greenhouse gases and is a sector affected by the impacts of climate change.
Climate Change and Primary Agricultural Production
Meeting the increasing demand for food is further challenged by the impacts of climate change. Impacts can include extreme events such as drought, floods, changing rain and temperature patterns. Collectively, this has a great impact on the agro-business sector. Food security is influenced by decreases in production in certain areas and incomes are at risks due to volatile food prices.
Agriculture remains the main income source for rural populations (2.5 billion). Already extreme weather events and diseases are reported to negatively affect agricultural production. As a result of climate change impacts, significant crop decrease in maize production of up to 30 percent by 2030 is expected in Africa and up to 10 percent for staple crops in Asia.
These changes call for adaptation measures such as new technologies and the cultivation of new crops. Studies predict the shortage of water and food for billions of people due to climate change.
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Adaptation to Climate Change
In view of growing food demand, successful adaptation to climate change must do more than just maintain the status quo. It requires the increase of production under inferior conditions. Therefore, adaptation strategies need to be broadly supported by institutions and policies and resulting legislation need to be modified. Targeted investments will be required and capacity development will be needed to achieve integrated action across diverse sectors. The complexity of the challenge has been highlighted in the report on the International Assessment of Agricultural Knowledge, Science and Technology for Development, published in 2009 (UNEP). The report also stresses the central role of the small-scale farming sector in meeting the challenges outlined above. Successful adaptation will require action on all scales: from subsistence farmers to the national frameworks and international agreements.
Broadly speaking, climate change adaptation will require the farmer/smallholder to
- shift to more robust crops or more stress-tolerant varieties,
- modify land use, e.g. trees in farmland,
- integrate soil cultivation and conservation,
- increase irrigated land, taking account of sustainable water management,
- integrate water harvesting technologies.
Whereas adapting our agricultural production systems to better deal with the effects of climate change is a central need, agriculture also contributes to climate change. Agricultural, food and other land use (AFOLU) represent 24 percent of total GHG emissions. Methane release in this context should not be overlooked. The flooding of rice fields, which creates anaerobic conditions, is a major contributor. Studies show that one third of all agricultural methane emissions derive from rice production.
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Climate Neutral Productivity Growth
Agriculture must produce more while faced with the impacts of a changing climate. More production growth needs to be achieved without further increasing the GHG load already in the atmosphere. From 2001 to 2011, carbon dioxide emissions from crop and livestock production increased from 4.7 billion tonnes to over 5.3 billion tonnes. This is equivalent to an increase of 14 percent. The use of fossil fuels and fossil-based energy needs to be reduced dramatically. Possible solutions include the introduction of renewables, optimization of processes and lowering of energy intensity. Land use needs to change so that it no longer releases GHG into the atmosphere but eventually builds up carbon stocks in soils and biomass. The same applies to agriculture, especially with regard to beef cattle farming and paddy rice production, which are now considered to be major methane emitters.
The potential for optimization in the supply of food is very much linked to the supply of energy. Abundant energy resources such as wind, solar, hydro and biomass energy are available. These technologies make on-site generation of electricity and thermal energy possible. The implementation is feasible on all scales, from subsistence farming to large-scale agriculture. Some technologies have improved significantly, both technically and economically: one example is the significant decrease in solar power plant prices.
Lowering energy intensity builds on behavioural changes, the development and implementation of low-carbon practices, and investment in improved technologies with a particular focus on energy efficiency. In the last three decades, the deployment of energy efficient practices has led to more efficient energy usage in high-GDP countries. The goal should be to globally enable the production of more food per unit of land with less energy inputs, calling for higher efficiency of energy use in agriculture. Besides reducing GHG emissions, this has the potential to make food production more resilient and less dependent on a fossil fuel-based energy supply.
An example of energy saving potential can be found in the highly energy-intensive processing of tea in Kenya. Read more about Energy Efficiency in the Kenyan tea sector here.
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Energy Input in Agricultural Value Chains
This unit focuses on agricultural value chains, discusses their indirect and direct energy inputs and explores the energy usage from production to processing, post-harvest and storage. Last but certainly not least, the financing side of alternative energy.
Figure 2: Energy Inputs in Agricultural Value Chains (Best, 2014)
Energy Input in Agricultural Production
Potential for climate change mitigation and hence for decreased GHG emissions lies in every single step of the agricultural value chain with its diverse direct and indirect energy inputs. Energy is used at every stage: from production over processing, post-harvest and storage to distribution and retail.
Direct and indirect energy inputs are equally necessary in agricultural value chains but they occur at different steps. Farms and processing plants apply direct energy at the operational level. It comprises, for instance, product supply and transport energy, with fuel or biofuel being used to bring the produce to the market. Additional energy consumed for production, processing and commercialization of products is categorized as direct energy input, as is energy for irrigation, land preparation and harvesting.
When correctly used, direct energy in irrigation systems has the potential to reduce water and energy consumption at the same time and further increase yield. If conventional energy sources are substituted by wind-powered or solar PV irrigation systems, [[Powering Agriculture: Irrigation|irrigation] can become sustainable. Nevertheless, sustainable irrigation also uses resources. With low-cost easily accessible energy in particular, there is a risk of over-exploitation.
Indirect energy is applied through the use of machinery, pesticides and fertilizers. A closer look at fertilizers, especially nitrogen fertilizers, clearly reveals the amount of energy input. Nitrogen fertilizer accounts for an energy input of 19.4 kWh per unit. Nonetheless, energy-intensive fertilizers have the potential to save indirect energy through advanced engineering and computer-aided technologies. Improving accuracy and timing of applications, with biosensors for soil fertility monitoring and trace gas detection, can significantly reduce fertilizer usage and thus decrease energy inputs.
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Energy Input in the Downstream Sector
The downstream sector in agricultural value chains includes processing, post-harvest, storage, cooling, distribution and retail. These activities can easily consume large amounts of energy, so energy efficiency measures and renewables are very important. Tobacco production in Zimbabwe is an example: the (heat) curing process accounts to over 50 percent of the total on-farm energy demand. The use of solar power can replace natural gas or liquefied petroleum gas in this heating process. There are several measures to preserve food. Cooling is one alternative to maintain food quality; however, its carbon footprint is by no means negligible. For some products, the total carbon footprint can amount to 10 percent and that’s only taking their refrigerated storage into account. If electricity inputs, the manufacturing of cooling equipment and lost refrigerants are considered, it is clear that GHG emissions from the refrigeration process are skyrocketing.
Energy consumption does not stop with the on-farm food operations and measures to preserve product quality. The processing and packaging part of the agricultural food chains is also a main contributor to overall energy utilization. A retail food product, for instance, needs around 14 kWh/kg to 28 kWh/kg for processing and packaging. Food processing plants in the USA are one example of this immense consumption of energy. The wet-milling of corn accounts for up to 15 percent of total energy used by the food industry. When not applying the best technologies, food processing plants are producing with an energy intensity up to 50 percent higher than necessary. By utilizing thermal and mechanical vapour compression, the milling of wet corn could save up to 15 to 20 percent in its energy-intensive dewatering, drying and evaporation process.
Small-scale food processing plants in developing countries often use outdated technologies and, as a result, consume more energy than necessary. The possibilities for improvement are abundant especially in regard to energy efficiency measures. Good maintenance of older processing plants can lead to energy savings of 10 to 20 percent without investing in new capital. By improving combustion efficiency, reusing the heat from exhaust gases and applying high-efficiency motors, energy savings of up to 20 to 30 percent are achievable. With higher capital investment, even higher energy saving can be achieved.
Transport is another consumer of energy in agricultural value chains. For instance, when transporting for fresh fruit by air or by road to markets several hundred kilometers away, transport can account for up to 50 to 70 percent of the total carbon footprint. However, only around 1percent of food products are transported by air, so that typically, the energy input for transport is a relatively small share of total energy inputs into an agricultural value chain. While transport is a relevant topic for the Energy-Agriculture Nexus, this course does not further elaborate on this topic but focuses on the value chain steps of primary production, storage and handling, and value added processing (Figure 2).
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Financing of Alternative Energy Solutions
Agricultural value chains contain many opportunities for energy efficiency measures and renewables. Investment in these sectors can yield significant savings in energy and reduce GHG emissions. Of course, alternative energy solutions come at a cost. Whether they are applicable is very much dependent on the individual situation and financial background. For instance, lack of access to the energy grid changes the opportunity costs dramatically and thus influences the decision-making process. Cost-benefit analysis and feasibility analysis are valuable to spark a decision.
External costs play a major role in relation to alternative energy solutions. “External costs” means that all costs are included – and that also means the costs to the environment when environment-unfriendly measures are used.
Clean energy solutions aim to increase dairy farm productivity and income, the improvements can play a major role in the livelihoods of smallholders. SunDanzer can be mentioned as one example. Recognizing the need for affordable cold-chain technologies, SunDanzer has developed a small-scale portable cooling system tailored for use in the Kenyan dairy market. Read more [[SunDanzer: Solar-Powered Refrigeration for Kenyan Dairy Farms|here].
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Population growth and limited resources
- The world’s human population will reach 9 billion by 2050 – demand for food will grow.
- Rapidly growing demand for resources in a resource limited world defined by planetary boundaries.
- The agri-food sector has to become more efficient to meet the growing demand.
- Around 30 percent of global energy usage can be traced back to the agri-food sector, including supply industry, agricultural production, processing, transport, merchandising and consumption.
- Extreme weather events due to climate change impact agricultural production.
- Adaptation measures need to be implemented, such as new technologies and cultivation of new crops.
- Introduction of renewables, optimization of processes and lowering of energy intensity can design productivity growth in a carbon-neutral way.
- Agricultural processing can mitigate climate change by increasing energy efficiency and by applying renewable energy technologies.
- Direct and indirect energy inputs are needed in agricultural value chains.
- Processing, post-harvest, storage and cooling are energy-intense steps of many agricultural value chains.
- Reduction of energy consumption in processing plants presents high potential for increasing energy efficiency.
- Options for financing alternative energy solutions is very much dependent on the individual context, such as the institutional setting.
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- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 FAO, 2011. Energy-smart food for people and climate, Issue paper, Food and Agriculture Organization of the United Nations. Available online at: http://www.fao.org/docrep/014/i2454e/i2454e00.pdf
- ↑ Godfray, H.C.J.; Beddington, J.R.; Crute, I.R.; Haddad, L.; Lawrence, D.; Muir, J.F.; Pretty, J.; Robinson, S.; Thomas, S.M.; Toulmin, C., 2010. Food Security: The Challenge of Feeding 9 Billion People. Science (2010) 327 (5967) 812-818.
- ↑ FAO, 2013. Climate smart agriculture – Sourcebook, Food and Agriculture Organization of the United Nations. Available online at: http://www.fao.org/docrep/018/i3325e/i3325e.pdf
- ↑ UNEP, 2009. International Assessment of Agricultural Knowledge, Science and Technology for Development, United Nations Environment Programme. Available online at http://www.unep.org/dewa/agassessment/reports/IAASTD/EN/Agriculture%20at%20a%20Crossroads_Global%20Report%20(English).pdf
- ↑ Tubiello, F.N. et al, 2014. Agriculture, Forestry and other land use emissions by sources and removals by sinks, ESS Working paper No. 2. Available online at: http://www.fao.org/docrep/019/i3671e/i3671e.pdf
- ↑ 6.0 6.1 6.2 6.3 6.4 6.5 Sims, R., Flammini, M., Puri, M., Bracco, S., 2015. Opportunities for agri-food chains to become energy-smart. Food and Agriculture Organization of the United Nations (FAO) and POWERING AGRICULTURE: An Energy Grand Challenge for Development (PAEGC). Available online at http://poweringag.org/docs/opportunitiesagri-food-chains-become-energy-smart
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