are not integrated with economic decisions, AKST will be reduced to contributing to the fulfillment of consumers' requirements regarding food and non-food products.
5.4.7 Energy and bioenergy
Increased demands are being levied on agriculture to provide energy and biomaterials. Bioenergy that includes the production of liquid fuels from biomass could meet some of the world's growing energy needs. It is unclear to what extent agriculture in NAE will become an energy producer, and how much can be achieved from other renewable energy sources and conservation. The development of bioenergy will increase competition for land and water resources and push up food prices. Social, technological and economic studies are badly needed.
5.4.7.1 Ongoing trends
Since World War II, global energy consumption has increased more than six-fold. In the same period, per capita energy demand has more than doubled. The energy demand growth rate is not slowing down in spite of record oil prices and global primary energy demand is expected to grow by more than 50% by 2030 (Fresco, 2006; IEA, 2006). According to the World Energy Outlook (IEA, 2006), in the reference scenario, the average annual percent change is expected to be 1.8 for the world, 3.0 for non-OECD Asia, 1.0 for the USA, 1.2 for Canada, 0.4 for OECD Europe and 1.3 for Russia. In the case of a low growth rate, the average annual percentage change is expected to be 1.4 for the world, 0.6 for the USA, 0.8 for Canada, 0.1 for OECD Europe and 0.8 for Russia.
Energy is a key driver in agriculture through the consumption of fossil fuels and fertilizer production. Agriculture also can be a source of energy. Energy consumption in agriculture depends on the type of crop, the production system and agroclimatic conditions and the farm size. Irrigation accounts for the largest share and is thus especially vulnerable to changes in energy prices. It has also been observed that the application of farmyard manure, another source of energy, has been decreasing over time. Application of mineral fertilizers, for improving yield and productivity has been on the increase but a stringent EU policy framework and related national policies have led to a decline in recent years (Wolf et al., 2005; EC, 2007). At present in the USA (Konyar, 2001), average direct and indirect energy account for 19% of the total variable costs, ranging from ten percent for soybeans and up to 27% for cotton. For irrigated crops, energy constitutes an average of 33% of the total variable cost, and ranges from 26% for hay to 51% for sorghum. These proportions could change with the use of biobased fuels. The availability and price of energy also influences the transport of agricultural products and hence global trade.
Biofuels that can be used for transport include bioetha-nol, biomethanol, biodiesel, biogas, biohydrogen and pure vegetable oil as well as solids such as agriculture and forestry wastes (Schröder and Weiske, 2006). The two primary biofuels in use today are ethanol and biodiesel, both of which can be used in existing vehicles. Ethanol is currently blended with gasoline, and biodiesel with petroleum-based diesel for use in conventional vehicles. Globally, ethanol accounts for |
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about 90% of total biofuel production, with biodiesel making up the rest (Marris, 2006; Sanderson, 2006). Global fuel ethanol production more than doubled between 2000 and 2005, while production of biodiesel, starting from a much smaller base, expanded nearly fourfold. By contrast, world oil production increased by only seven percent during the same period.
Petroleum refining is being developed on a very large scale; biofuels are produced in lower volumes and, currently, much more decentralized. According to the World Energy Outlook (IEA, 2006), significant technological challenges still need to be overcome for the second-generation technologies to become commercially viable. In the case of biodiesel in particular, where a wide range of plant and animal feedstock can be used, production facilities tend to be rather dispersed. Ethanol fuel production has tended to be more geographically concentrated than biodiesel e.g., in the United States, predominantly in the Midwestern states that have abundant corn supplies (Worldwatch Institute, 2006).
The various biomass feedstock used for producing biofuels can be grouped into two basic categories. The first is the currently available "first-generation" feedstock, composed of various grain and vegetable crops that are harvested for their sugar, starch, or oil content and can be converted into liquid fuels using conventional technology. The yields from the feedstock vary considerably, with sugar cane and palm oil currently producing the largest volumes per hectare (Marris, 2006). By contrast, the "next-generation" biofuel feedstock comprising cellulose-rich organic material will be harvested for its total biomass (Fresco, 2006). To convert these fibers into liquid biofuels requires advanced technical processes, many of which are still under development. Advanced biofuel technologies could allow biofuels to replace 37% of US gasoline within the next 25 years, with the figure rising to 75% if vehicle fuel efficiency were doubled during that same period. The biofuel potential of EU countries is in the range of 20-25% (EEA, 2006) if strong sustainability criteria for land use and crop choice are applied and bioenergy use in non-transport sectors grows in parallel.
5.4.7.2 Uncertainties of the future
As far as energy and bioenergy are concerned, there are three major uncertainties for the future:
• To what extent will bioenergy supply develop globally?
• Which considerations will determine future bioenergy use in NAE?
• Will agriculture be able to substantially reduce energy required for production?
• What will be the consequences of bioenergy production on food prices and water usage?
Among the major considerations in NAE that will influence the energy market will be the energy security aspect. Second, there will be the increasing awareness of the need to protect the Earth's climate system through the reduction of greenhouse gas emissions (GHG). The recent (March 2007) agreement of EU leaders on greenhouse reduction targets and renewable energy use is a milestone that may well trigger changes in energy policy elsewhere (i.e., the US, Russia, China). There continues to be a lively debate regarding the trade-offs between economic growth and energy. Some ex- |