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Energy, land, and food: Vital connections
Energy in Agriculture, 3 (1984) 267--275 Elsevier Science Publishers B.V., Amsterdam -- Printed in The Netherlands
267
ENERGY, LAND, AND FOOD: VITAL CONNECTIONS
RICHARD C. FLUCK
Institute of Food and Agricultural Sciences, Agricultural Engineering Department, University of Florida, Gainesville, FL 32611 (U.S.A.) (Accepted 4 October 1984)
ABSTRACT Fluck, R.C., 1984. Energy, land, and food: vital connections. Energy Agric., 3: 267--275. A basic perspective of energy, land, and food reveals vital connections. A rationale for the use of energy is examined as a fundamental premise through identification of the effects of degree of industrialization on a food system. Recognition of the pervasive role of energy as an input to industrialized agriculture and its interactions with land and other inputs are leading to their more efficient use. Conservation is resulting in increasing energy productivity in production (especially with respect to irrigation, fertilization and crop drying), processing, transportation, distribution, and food preparation. Categories of energy conservation and the time scale of conservation practices are examined for their implications. Additional effects of the energy situation are examined, including production shifts, changing patterns of consumption, and the intensiveness of agricultural production. Appropriate technology for the food chain in an energy-short future is examined.
INTRODUCTION C u r r e n t f o o d p r o d u c t i o n and d i s t r i b u t i o n s y s t e m s have evolved over decades a n d have been s h a p e d b y n u m e r o u s forces, o n e o f w h i c h has been relatively inexpensive, readily available energy. In t h e industrialized w o r l d t h o s e f o o d systems are q u i t e c o m p l e x w i t h m a n y separate b u t interrelated c o m p o nents. Vital c o n n e c t i o n s exist a m o n g these c o m p o n e n t s w h i c h a f f e c t e n e r g y c o n s u m p t i o n and t h e r e f o r e a f f e c t e f f o r t s t o conserve e n e r g y or increase e n e r g y p r o d u c t i v i t y . These vital c o n n e c t i o n s n e e d t o be identified and unders t o o d in o r d e r t o d e v e l o p f o o d systems m o r e capable o f m e e t i n g f u t u r e e n e r g y situations. E x a m p l e s o f t h e areas in o u r f o o d s y s t e m s w h e r e vital c o n n e c t i o n s exist w h i c h a f f e c t e n e r g y ( F l u c k and Baird, 1 9 8 0 ) i n c l u d e t h e c h o i c e o f p r o d u c t i o n i n p u t s and their a m o u n t s a n d the r e s u l t a n t o u t p u t s or yields; selection a m o n g various alternative p r o d u c t i o n inputs; choices o f t y p e s a n d a m o u n t s o f f o o d c o n s u m e d and r e s u l t a n t e n e r g y i n p u t s required; degree o f f o o d proFlorida Agricultural Experiment Station Journal Series No. 4464. 0167-5826/84/$03.00
© 1984 Elsevier Science Publishers B.V.
268
cessing and resultant energy required; and individual and collective decisions concerning conservation, technology and management and resultant energy conservation. Specific attention is now being directed to the effective utilization of energy in food systems, a departure from previous practice. SITUATIONAL ASPECTS OF ENERGY FOR FOOD
Table I depicts energy consumption for the United States f o o d system, as an example of an industrialized f o o d system. Energy includes all fuels, electricity, etc., b u t not human energy. It includes the direct energy and the indirect energy. This example is presented to illustrate the scope, complexity and relative importance of various categories of energy as a necessary input to an industrialized food system. An appreciation of h o w energy is used is necessary to intelligently deal with the situation. Annual energy consumption is categorized by stage of the f o o d system and b y whether the energy is consumed directly or as indirect consummable energy or as indirect capital energy. TABLE I U.S. Food system energy consumption for the early 1970's a
Stage of
food system
EJ/year
(percent in
Direct
parentheses)
Indirect
Total
Consummable Capital Agricultural Production Food Manufacturing Food Distribution Food Preparation Waste Disposal Transportation
1.50 1.40 0.95 3.90 0.05 1.58
(10.5) c (9.8) c (6.7) d (27.4) 5 (0.4) (11.1) c
Total
9.38 (65.9)
0.76 1.98 0.08 0.37 0.07 0.11
(5.3) d (13.9) c (0.6) (2.6) d (0.5) (0.8)
3.37 (23.7)
0.53 0.06 0.05 0.37 0.05 0.42
(3.7) d (0.4) (0.4) (2.6) d (0.4) (3.0) d
1.48 (10.4)
2.79 3.44 1.08 4.64 0.17 2.11
(19.6) (24.2) (7.6) (32.6) (1.2) (14.8)
14.23 (100.0)
aBooz, Allen and Hamilton, Inc., 1976; Bullard et al., 1976; U.S. Bur. Census, 1978. bCategory of largest energy use. c Categories of second level of energy use. dCategories of third level of energy use.
The preparation of f o o d consumes almost one third (32.6%) of the entire energy requirement of the f o o d system. Following in relative importance are f o o d manufacturing (24.2%), agricultural production (19.6%), transportation (14.8%), f o o d distribution (7.6%) and waste disposal (1.2%). Direct energy accounts for almost two thirds (65.9%) of the total, whereas indirect consumable energy accounts for less than one fourth (23.7%) and indirect capital energy a b o u t one tenth (10.4%) of the total.
269
Direct energy used in food preparation is the single largest category of energy consumption at 27.4%. Four categories, indirect consummable in food manufacturing (13.9%), direct in transportation (11.1%), direct in agricultural production (10.5%) and direct in food manufacturing (9.8%), form the second tier of categories in relative importance. Following these are six other categories using 2.6--6.7% of the total food system energy consumption: direct in food distribution; indirect consummable in agricultural production, indirect capital in agricultural production, indirect capital in transportation, indirect consummable in food preparation and indirect capital in food preparation. The remaining seven categories are of less importance, totalling 3.3%. Energy is only one of many inputs necessary for a food system to function. Figure 1 depicts, for agricultural production, energy and other inputs with which energy interacts and complements, competes, and may substitute
Fig. 1. Inputs used in agricultural production.
PRIMARY ENERGY NON-RENEWABLE "~ CRUDE OIL NATURAL GAS COAL URANIUM RENEWABLE SOLAR
THERMAL ~"I PHOTOVOLTAIC HYDRO WIND
BIONIASS GEOTHERMAL OTEC WASTES
AGRICULTURAL PRODUCTION INPUTS f'DIRECT FUELS ELECTRIC POWER INDIRECT CONSUMMABLE FERTILIZERS PESTICIDES CAPITAL MACHINERY BUILDINGS IRRIGATION EQUIP LABOR DRAFT ANIMALS
.J
Fig. 2. Pervasive role of energy as a product input.
270 for. Similar circumstances exist for other stages of the food system. Not only is energy used directly, but it also serves as an indirect input in m a n y of the other inputs necessary for food systems to function. Figure 2 indicates the pervasive role of energy in these inputs as well as the connection to the various sources from which we obtain energy. EFFICIENCY OF ENERGY USE Within the past decade energy has become a major concern in industrialized food systems. The problem which confronts society is how to efficiently use energy in providing food, but to use it in the context of the real world which evidences complex connections between the efficient use of energy and other, often conflicting, goals. When examining energy separately, a reasonable goal is to use energy efficiently, particularly when to do so also decreases, or at least does not increase, the m o n e t a r y cost of agricultural commodities and food products. Normative criteria we may apply to measure the efficient use of energy (Fluck, 1979) include: (a) energy productivity; and (b) energy ratio. In order to use either, an energy analysis of the system under study must be performed. Energy analysis is, however, yet under development and has unresolved problems (Fluck, 1980) related to such questions as energy quality, boundary placement, and multiple outputs. Results must therefore by used with care. Desirable actions resulting from considerations of energy use might include the conservation of energy, the development of new technology for the use of energy, and the development of new sources of energy. All this is, of course, being done. Examination of energy productivity as a criteria for the use of energy in a food production system is in order. Energy productivity (Fluck, 1979) is simply the quantity of an agricultural or food product produced, divided by the summation of all primary energy inputs required for its production (with convenient units: kg/MJ). Comparison of energy productivity should be limited to one product at one time and location. Several approaches exist for improvement of energy productivity, not all related specifically to energy. Included are: energy conservation; the substitution for direct energy inputs by non-energy inputs or by renewable energy inputs; the substitution of lessenergy-intensive inputs for higher-energy-intensive inputs; the use of new technology requiring less energy; and the use of new technology which increases production. Not every such practice will always improve energy productivity, however, since both numerator and denominator can change in either direction with changed production practices. Figure 3 shows, for agricultural production, how changes in both yield and energy inputs from a base position can increase or decrease energy productivity. Diagonal lines indicate percent changes in energy productivity. A system improvement which both reduces energy inputs and increases yield (area 2 on the figure), leads to the greatest increases in energy productivity. A system change which reduces yield, if energy inputs are sufficiently reduced (area 1 on the figure),
271
can lead to increased energy productivity. A system change which requires increased inputs, if yields are sufficiently increased (area 3 on the figure), can also lead to increased energy productivity. More often than not, increases in the level of consumption of a single input, even when resulting in increased yield, lead to decreased energy productivity. This is due simply to the fact t h a t production is located higher on a curve of decreasing returns. The challenge therefore is to instead find those breakthrough areas where yields are increased substantially with small or no increases in total energy inputs. These are the desirable areas where sharp improvements in energy productivity can occur. Energy inputs may have either or both of two purposes; to increase yield, (yield intensive) or to substitute for other inputs such as land and labor. Prior emphasis has been on the latter but future emphasis is expected to center more on those which increase energy productivity. | % CHANGE •
/
/
3 7
../
..f~--7
~...,
^o|?.J IN ENERGY
Fig. 3. Effects of changes in yield and energy inputs on energy productivity.
DEGREE OF INDUSTRIALIZATION
An important issue and determinant of how energy is used in food systems is the degree or level of industrialization. The effects of degree of industrialization on a food system are many; an a t t e m p t is made in Fig. 4 to list them. They are stated as generalities; exceptions certainly exist. Identification of these effects m a y be useful, for instance, to a developing c o u n t r y in whose hands the decision may lie as to what extent to industrialize their food system. Less industrialization generally is associated with higher energy produc-
272 tivity, less depletion of certain resources, a greater degree of producer selfsufficiency, less interdependence, a simpler lifestyle, and reduced pollution. More industrialization is generally associated with higher land productivity, higher labor productivity, more food production, a smaller portion of the labor force employed in the food system, greater specialization and resultant more efficient agricultural production, higher quality food, a greater variety of food, and an increased standard of living. Mankind seems almost universally willing to forego the benefits of less industrialization in order to achieve the benefits of increased industrialization whenever that choice exists. That preference serves therefore as rationale for the use of large quantities of primary energy as inputs to our food systems, insofar as industrialization creates the conditions necessitating increased energy inputs. Jz
~
M
O
R
E
LESS/I\
HIGHER LAND PRODUCTIVITY HIGHER LABOR PRODUCTIVITY MORETOTAL FOODPRODUCED HIGHER ENERGY PRODUCTIVITY SMALLERPORTIONOF LABOR (USUALLY,NOT IN EVERYCASE) FORCE IN FOODCHAIN LESS DEPLETIONOF SMALLER PORTIONOF INCOME CERTAIN RESOURCES SPENT ON FOOD GREATER SELF SUFFICIENCY MORE EFFICIENT PRODUCTION ~ESS NT,ERDEPENDENCE DUE TO GREATER SPECIALIZATION 'SIMPLER' LIFESTYLE HIGHER QUALITY FOOD REDUCED POLLUTION GREATER VARIETY OF FOOD INCREASED STANDARDOF LIVING
Fig. 4. Effects of degree of industrialization of food chain. ENERGY CONSERVATION -- BACKGROUND Both agricultural and food industry have undergone, as has all industry (Schipper and Darmstadter, 1978), several phases of energy awareness and response since the 1973--74 'energy crisis'. Prior, an era of cheap energy had existed in which energy had been substituted freely for other inputs. The supply disruptions of the OPEC oil embargo brought shock and confusion. Much concern at t h a t time was focused on supply and availability, and energy policy focused on quotas and allotments. Later actions consisted to a great extent in substituting one source of energy for another and the stockpiling of reserves. The earliest conservation efforts were seen as doing w i t h o u t rather than doing with less; belt tightening, behavior modification, and the altering of demand patterns were watchwords of the day. Later, a different kind of energy conservation effort occurred; equipment modifications were made to reduce energy consumption, retrofitting was performed, and capital was substituted for energy; each involved conserving w i t h o u t doing without. A longer range conservation effort is now occurring; old equipment is being
273
replaced with new, energy- efficient equipment, and capital continues to substitute for energy. Further, new technology which is energy conserving is being developed and utilized. The future seems likely to include further substitutions of other inputs for energy as has occurred with capital. A question of significant importance is whether or under what circumstances and to what degree labor will replace significant quantities of energy. Labor seems not to have replaced energy to any extent to date, as might be expected due to the high cost of labor with respect to energy. An examination of the typical time scale of energy conservation activities suggests three subdivisions. Near-term energy conservation activities are of the 'housekeeping' sort which involve low capital outlay and higher returns. Mid-term activities involve improvements in energy efficiency using existing technology, and long term activities involve the application of advances in energy technology. It is further suggested that individuals and firms differ as to entry date into this sequence and therefore some are not y e t involved in conservation activities or are involved in near-term activities whereas others have at the same time progressed further. Another important aspect of energy conservation is the three types of energy conservation into which the aggregate of all energy conservation can be subdivided. The categories relate to the reason for which conservation occurs. One is price-induced whereby less energy is used due to higher energy prices. A second is economy-induced in which less energy is used due to less demand and less production. The current recession has caused significant economy-induced energy conservation; demand will increase as the recession ends. The third is investment-induced in which less energy is used due to capital expenditures in energy conserving equipment. True conservation includes price-induced and investment-induced. Economy-induced reductions in energy consumption m a y be mistaken for conservation. Of importance also is that normal replacement of equipment allows the o p p o r t u n i t y to reduce energy consumption at low or no additional cost due to improvements in equipment-related energy consumption. Also of importance is the fact that, in a climate of economic rationality, the decisions which are made t h a t conserve energy are mainly those which also result in increased profits or reduced costs. In other words, increased expected profits or reduced costs are prerequisite to and necessary for energy conservation. Finally, it is useful to have some idea of how much energy conservation may be possible. Recent data indicated, for example, that, between 1974 and 1981, the United States had reduced energy consumption 23% in industry, 14% in commerce, and 10% in the home. These reductions will likely be sharply surpassed sometime in the future, since second law energy efficiencies for familiar energy-consuming equipment and activities indicate that substantial further reductions in energy consumption are at least theoretically possible.
274 FUTURE EFFECTS OF ENERGY ON THE FOOD SYSTEM
Some effects of the energy situation on agriculture and the f o o d system are already evident in direction if not extent. Examples include agricultural practices currently in trouble in some areas due to high energy costs, including greenhouses, feedlot beef finishing, deep well irrigation, and artificial drying of some crops. Other effects are perhaps presently perceived quite dimly if at all. Among the continuing and expected future effects are changes in the agricultural commodities produced, changes in the geographic areas in which some commodities are produced, localized diversification to better utilize agricultural wastes, the consumption of less energy commensurate with the increased consumption of certain other inputs, and less consumption of certain energy intensive inputs. In aggregate, these changes are occurring slowly but steadily. Among the possible effects of the energy situation on the remainder of the food system are less processing, less packaging, the increased use of lessenergy-intensive m e t h o d s of food preservation and processing, less personal travel to purchase or consume food, a decreased variety of f o o d available for consumer purchase, and higher priced food. The term 'energy crisis' is not heard frequently anymore, having been for the most replaced in our vocabularly with expressions such as 'energy situation'. Nevertheless, the unescapable and inexorable future is that, without some energy source breakthrough, which would bring with it a whole new set of problems, energy will become relatively m o r e important in our scheme of things, f o o d production included. I believe that efforts directed at the interface of food and energy; at the vital connections between energy, land, other resources, and food; will prove challenging, exciting and rewarding. A former U.S. Senator said that the only difference between an optimist and a pessimist is that the pessimist is better informed. If she is correct, then I must plead guilty to at least a certain degree of ignorance on the subject, for I believe if mankind can control our own numbers, then we can feed ourselves using our available energy resources and ultimately, if needed, using only our renewable energy resources.
REFERENCES Booz, Allen and Hamilton, Inc., 1976. Energy Use in the Food System. Federal Energy Administration, Washington, DC. Bullard, C.W., Penner, P.S. and Pilati, D.A., 1976. Energy Analysis Handbook, CAC Doc. 214, Center for Advanced Computation, University of Illinois, Urbana, IL, 70 pp. Fluck, R.C., 1979. Energy productivity: a measure of energy utilization in agricultural systems. Agric. Syst., 4(1): 29--37. Fluck, R.C., 1980. Fundamentals of energy analysis for agriculture. In: Agricultural Energy. Vol. 1, Solar Energy and Livestock Production. Proc. ASAE National Energy
275 Symposium, 29 September-1 October 1980, Kansas City, MO. American Society of Agricultural Engineers, St. Joseph, MI, pp. 208--211. Fluck, R.C. and Baird, C.D., 1980. Agricultural Energetics. AVI, Westport, CT, 192 pp. Schipper, L. and Darmstadter, J., 1978. The logic of energy conservation. Tech. Rev., 80(3): 41--50. U.S. Bur. Census, 1978. Statistical Abstract of the United States. U.S. Bureau of the Census, Washington, DC, 1057 pp.
267
ENERGY, LAND, AND FOOD: VITAL CONNECTIONS
RICHARD C. FLUCK
Institute of Food and Agricultural Sciences, Agricultural Engineering Department, University of Florida, Gainesville, FL 32611 (U.S.A.) (Accepted 4 October 1984)
ABSTRACT Fluck, R.C., 1984. Energy, land, and food: vital connections. Energy Agric., 3: 267--275. A basic perspective of energy, land, and food reveals vital connections. A rationale for the use of energy is examined as a fundamental premise through identification of the effects of degree of industrialization on a food system. Recognition of the pervasive role of energy as an input to industrialized agriculture and its interactions with land and other inputs are leading to their more efficient use. Conservation is resulting in increasing energy productivity in production (especially with respect to irrigation, fertilization and crop drying), processing, transportation, distribution, and food preparation. Categories of energy conservation and the time scale of conservation practices are examined for their implications. Additional effects of the energy situation are examined, including production shifts, changing patterns of consumption, and the intensiveness of agricultural production. Appropriate technology for the food chain in an energy-short future is examined.
INTRODUCTION C u r r e n t f o o d p r o d u c t i o n and d i s t r i b u t i o n s y s t e m s have evolved over decades a n d have been s h a p e d b y n u m e r o u s forces, o n e o f w h i c h has been relatively inexpensive, readily available energy. In t h e industrialized w o r l d t h o s e f o o d systems are q u i t e c o m p l e x w i t h m a n y separate b u t interrelated c o m p o nents. Vital c o n n e c t i o n s exist a m o n g these c o m p o n e n t s w h i c h a f f e c t e n e r g y c o n s u m p t i o n and t h e r e f o r e a f f e c t e f f o r t s t o conserve e n e r g y or increase e n e r g y p r o d u c t i v i t y . These vital c o n n e c t i o n s n e e d t o be identified and unders t o o d in o r d e r t o d e v e l o p f o o d systems m o r e capable o f m e e t i n g f u t u r e e n e r g y situations. E x a m p l e s o f t h e areas in o u r f o o d s y s t e m s w h e r e vital c o n n e c t i o n s exist w h i c h a f f e c t e n e r g y ( F l u c k and Baird, 1 9 8 0 ) i n c l u d e t h e c h o i c e o f p r o d u c t i o n i n p u t s and their a m o u n t s a n d the r e s u l t a n t o u t p u t s or yields; selection a m o n g various alternative p r o d u c t i o n inputs; choices o f t y p e s a n d a m o u n t s o f f o o d c o n s u m e d and r e s u l t a n t e n e r g y i n p u t s required; degree o f f o o d proFlorida Agricultural Experiment Station Journal Series No. 4464. 0167-5826/84/$03.00
© 1984 Elsevier Science Publishers B.V.
268
cessing and resultant energy required; and individual and collective decisions concerning conservation, technology and management and resultant energy conservation. Specific attention is now being directed to the effective utilization of energy in food systems, a departure from previous practice. SITUATIONAL ASPECTS OF ENERGY FOR FOOD
Table I depicts energy consumption for the United States f o o d system, as an example of an industrialized f o o d system. Energy includes all fuels, electricity, etc., b u t not human energy. It includes the direct energy and the indirect energy. This example is presented to illustrate the scope, complexity and relative importance of various categories of energy as a necessary input to an industrialized food system. An appreciation of h o w energy is used is necessary to intelligently deal with the situation. Annual energy consumption is categorized by stage of the f o o d system and b y whether the energy is consumed directly or as indirect consummable energy or as indirect capital energy. TABLE I U.S. Food system energy consumption for the early 1970's a
Stage of
food system
EJ/year
(percent in
Direct
parentheses)
Indirect
Total
Consummable Capital Agricultural Production Food Manufacturing Food Distribution Food Preparation Waste Disposal Transportation
1.50 1.40 0.95 3.90 0.05 1.58
(10.5) c (9.8) c (6.7) d (27.4) 5 (0.4) (11.1) c
Total
9.38 (65.9)
0.76 1.98 0.08 0.37 0.07 0.11
(5.3) d (13.9) c (0.6) (2.6) d (0.5) (0.8)
3.37 (23.7)
0.53 0.06 0.05 0.37 0.05 0.42
(3.7) d (0.4) (0.4) (2.6) d (0.4) (3.0) d
1.48 (10.4)
2.79 3.44 1.08 4.64 0.17 2.11
(19.6) (24.2) (7.6) (32.6) (1.2) (14.8)
14.23 (100.0)
aBooz, Allen and Hamilton, Inc., 1976; Bullard et al., 1976; U.S. Bur. Census, 1978. bCategory of largest energy use. c Categories of second level of energy use. dCategories of third level of energy use.
The preparation of f o o d consumes almost one third (32.6%) of the entire energy requirement of the f o o d system. Following in relative importance are f o o d manufacturing (24.2%), agricultural production (19.6%), transportation (14.8%), f o o d distribution (7.6%) and waste disposal (1.2%). Direct energy accounts for almost two thirds (65.9%) of the total, whereas indirect consumable energy accounts for less than one fourth (23.7%) and indirect capital energy a b o u t one tenth (10.4%) of the total.
269
Direct energy used in food preparation is the single largest category of energy consumption at 27.4%. Four categories, indirect consummable in food manufacturing (13.9%), direct in transportation (11.1%), direct in agricultural production (10.5%) and direct in food manufacturing (9.8%), form the second tier of categories in relative importance. Following these are six other categories using 2.6--6.7% of the total food system energy consumption: direct in food distribution; indirect consummable in agricultural production, indirect capital in agricultural production, indirect capital in transportation, indirect consummable in food preparation and indirect capital in food preparation. The remaining seven categories are of less importance, totalling 3.3%. Energy is only one of many inputs necessary for a food system to function. Figure 1 depicts, for agricultural production, energy and other inputs with which energy interacts and complements, competes, and may substitute
Fig. 1. Inputs used in agricultural production.
PRIMARY ENERGY NON-RENEWABLE "~ CRUDE OIL NATURAL GAS COAL URANIUM RENEWABLE SOLAR
THERMAL ~"I PHOTOVOLTAIC HYDRO WIND
BIONIASS GEOTHERMAL OTEC WASTES
AGRICULTURAL PRODUCTION INPUTS f'DIRECT FUELS ELECTRIC POWER INDIRECT CONSUMMABLE FERTILIZERS PESTICIDES CAPITAL MACHINERY BUILDINGS IRRIGATION EQUIP LABOR DRAFT ANIMALS
.J
Fig. 2. Pervasive role of energy as a product input.
270 for. Similar circumstances exist for other stages of the food system. Not only is energy used directly, but it also serves as an indirect input in m a n y of the other inputs necessary for food systems to function. Figure 2 indicates the pervasive role of energy in these inputs as well as the connection to the various sources from which we obtain energy. EFFICIENCY OF ENERGY USE Within the past decade energy has become a major concern in industrialized food systems. The problem which confronts society is how to efficiently use energy in providing food, but to use it in the context of the real world which evidences complex connections between the efficient use of energy and other, often conflicting, goals. When examining energy separately, a reasonable goal is to use energy efficiently, particularly when to do so also decreases, or at least does not increase, the m o n e t a r y cost of agricultural commodities and food products. Normative criteria we may apply to measure the efficient use of energy (Fluck, 1979) include: (a) energy productivity; and (b) energy ratio. In order to use either, an energy analysis of the system under study must be performed. Energy analysis is, however, yet under development and has unresolved problems (Fluck, 1980) related to such questions as energy quality, boundary placement, and multiple outputs. Results must therefore by used with care. Desirable actions resulting from considerations of energy use might include the conservation of energy, the development of new technology for the use of energy, and the development of new sources of energy. All this is, of course, being done. Examination of energy productivity as a criteria for the use of energy in a food production system is in order. Energy productivity (Fluck, 1979) is simply the quantity of an agricultural or food product produced, divided by the summation of all primary energy inputs required for its production (with convenient units: kg/MJ). Comparison of energy productivity should be limited to one product at one time and location. Several approaches exist for improvement of energy productivity, not all related specifically to energy. Included are: energy conservation; the substitution for direct energy inputs by non-energy inputs or by renewable energy inputs; the substitution of lessenergy-intensive inputs for higher-energy-intensive inputs; the use of new technology requiring less energy; and the use of new technology which increases production. Not every such practice will always improve energy productivity, however, since both numerator and denominator can change in either direction with changed production practices. Figure 3 shows, for agricultural production, how changes in both yield and energy inputs from a base position can increase or decrease energy productivity. Diagonal lines indicate percent changes in energy productivity. A system improvement which both reduces energy inputs and increases yield (area 2 on the figure), leads to the greatest increases in energy productivity. A system change which reduces yield, if energy inputs are sufficiently reduced (area 1 on the figure),
271
can lead to increased energy productivity. A system change which requires increased inputs, if yields are sufficiently increased (area 3 on the figure), can also lead to increased energy productivity. More often than not, increases in the level of consumption of a single input, even when resulting in increased yield, lead to decreased energy productivity. This is due simply to the fact t h a t production is located higher on a curve of decreasing returns. The challenge therefore is to instead find those breakthrough areas where yields are increased substantially with small or no increases in total energy inputs. These are the desirable areas where sharp improvements in energy productivity can occur. Energy inputs may have either or both of two purposes; to increase yield, (yield intensive) or to substitute for other inputs such as land and labor. Prior emphasis has been on the latter but future emphasis is expected to center more on those which increase energy productivity. | % CHANGE •
/
/
3 7
../
..f~--7
~...,
^o|?.J IN ENERGY
Fig. 3. Effects of changes in yield and energy inputs on energy productivity.
DEGREE OF INDUSTRIALIZATION
An important issue and determinant of how energy is used in food systems is the degree or level of industrialization. The effects of degree of industrialization on a food system are many; an a t t e m p t is made in Fig. 4 to list them. They are stated as generalities; exceptions certainly exist. Identification of these effects m a y be useful, for instance, to a developing c o u n t r y in whose hands the decision may lie as to what extent to industrialize their food system. Less industrialization generally is associated with higher energy produc-
272 tivity, less depletion of certain resources, a greater degree of producer selfsufficiency, less interdependence, a simpler lifestyle, and reduced pollution. More industrialization is generally associated with higher land productivity, higher labor productivity, more food production, a smaller portion of the labor force employed in the food system, greater specialization and resultant more efficient agricultural production, higher quality food, a greater variety of food, and an increased standard of living. Mankind seems almost universally willing to forego the benefits of less industrialization in order to achieve the benefits of increased industrialization whenever that choice exists. That preference serves therefore as rationale for the use of large quantities of primary energy as inputs to our food systems, insofar as industrialization creates the conditions necessitating increased energy inputs. Jz
~
M
O
R
E
LESS/I\
HIGHER LAND PRODUCTIVITY HIGHER LABOR PRODUCTIVITY MORETOTAL FOODPRODUCED HIGHER ENERGY PRODUCTIVITY SMALLERPORTIONOF LABOR (USUALLY,NOT IN EVERYCASE) FORCE IN FOODCHAIN LESS DEPLETIONOF SMALLER PORTIONOF INCOME CERTAIN RESOURCES SPENT ON FOOD GREATER SELF SUFFICIENCY MORE EFFICIENT PRODUCTION ~ESS NT,ERDEPENDENCE DUE TO GREATER SPECIALIZATION 'SIMPLER' LIFESTYLE HIGHER QUALITY FOOD REDUCED POLLUTION GREATER VARIETY OF FOOD INCREASED STANDARDOF LIVING
Fig. 4. Effects of degree of industrialization of food chain. ENERGY CONSERVATION -- BACKGROUND Both agricultural and food industry have undergone, as has all industry (Schipper and Darmstadter, 1978), several phases of energy awareness and response since the 1973--74 'energy crisis'. Prior, an era of cheap energy had existed in which energy had been substituted freely for other inputs. The supply disruptions of the OPEC oil embargo brought shock and confusion. Much concern at t h a t time was focused on supply and availability, and energy policy focused on quotas and allotments. Later actions consisted to a great extent in substituting one source of energy for another and the stockpiling of reserves. The earliest conservation efforts were seen as doing w i t h o u t rather than doing with less; belt tightening, behavior modification, and the altering of demand patterns were watchwords of the day. Later, a different kind of energy conservation effort occurred; equipment modifications were made to reduce energy consumption, retrofitting was performed, and capital was substituted for energy; each involved conserving w i t h o u t doing without. A longer range conservation effort is now occurring; old equipment is being
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replaced with new, energy- efficient equipment, and capital continues to substitute for energy. Further, new technology which is energy conserving is being developed and utilized. The future seems likely to include further substitutions of other inputs for energy as has occurred with capital. A question of significant importance is whether or under what circumstances and to what degree labor will replace significant quantities of energy. Labor seems not to have replaced energy to any extent to date, as might be expected due to the high cost of labor with respect to energy. An examination of the typical time scale of energy conservation activities suggests three subdivisions. Near-term energy conservation activities are of the 'housekeeping' sort which involve low capital outlay and higher returns. Mid-term activities involve improvements in energy efficiency using existing technology, and long term activities involve the application of advances in energy technology. It is further suggested that individuals and firms differ as to entry date into this sequence and therefore some are not y e t involved in conservation activities or are involved in near-term activities whereas others have at the same time progressed further. Another important aspect of energy conservation is the three types of energy conservation into which the aggregate of all energy conservation can be subdivided. The categories relate to the reason for which conservation occurs. One is price-induced whereby less energy is used due to higher energy prices. A second is economy-induced in which less energy is used due to less demand and less production. The current recession has caused significant economy-induced energy conservation; demand will increase as the recession ends. The third is investment-induced in which less energy is used due to capital expenditures in energy conserving equipment. True conservation includes price-induced and investment-induced. Economy-induced reductions in energy consumption m a y be mistaken for conservation. Of importance also is that normal replacement of equipment allows the o p p o r t u n i t y to reduce energy consumption at low or no additional cost due to improvements in equipment-related energy consumption. Also of importance is the fact that, in a climate of economic rationality, the decisions which are made t h a t conserve energy are mainly those which also result in increased profits or reduced costs. In other words, increased expected profits or reduced costs are prerequisite to and necessary for energy conservation. Finally, it is useful to have some idea of how much energy conservation may be possible. Recent data indicated, for example, that, between 1974 and 1981, the United States had reduced energy consumption 23% in industry, 14% in commerce, and 10% in the home. These reductions will likely be sharply surpassed sometime in the future, since second law energy efficiencies for familiar energy-consuming equipment and activities indicate that substantial further reductions in energy consumption are at least theoretically possible.
274 FUTURE EFFECTS OF ENERGY ON THE FOOD SYSTEM
Some effects of the energy situation on agriculture and the f o o d system are already evident in direction if not extent. Examples include agricultural practices currently in trouble in some areas due to high energy costs, including greenhouses, feedlot beef finishing, deep well irrigation, and artificial drying of some crops. Other effects are perhaps presently perceived quite dimly if at all. Among the continuing and expected future effects are changes in the agricultural commodities produced, changes in the geographic areas in which some commodities are produced, localized diversification to better utilize agricultural wastes, the consumption of less energy commensurate with the increased consumption of certain other inputs, and less consumption of certain energy intensive inputs. In aggregate, these changes are occurring slowly but steadily. Among the possible effects of the energy situation on the remainder of the food system are less processing, less packaging, the increased use of lessenergy-intensive m e t h o d s of food preservation and processing, less personal travel to purchase or consume food, a decreased variety of f o o d available for consumer purchase, and higher priced food. The term 'energy crisis' is not heard frequently anymore, having been for the most replaced in our vocabularly with expressions such as 'energy situation'. Nevertheless, the unescapable and inexorable future is that, without some energy source breakthrough, which would bring with it a whole new set of problems, energy will become relatively m o r e important in our scheme of things, f o o d production included. I believe that efforts directed at the interface of food and energy; at the vital connections between energy, land, other resources, and food; will prove challenging, exciting and rewarding. A former U.S. Senator said that the only difference between an optimist and a pessimist is that the pessimist is better informed. If she is correct, then I must plead guilty to at least a certain degree of ignorance on the subject, for I believe if mankind can control our own numbers, then we can feed ourselves using our available energy resources and ultimately, if needed, using only our renewable energy resources.
REFERENCES Booz, Allen and Hamilton, Inc., 1976. Energy Use in the Food System. Federal Energy Administration, Washington, DC. Bullard, C.W., Penner, P.S. and Pilati, D.A., 1976. Energy Analysis Handbook, CAC Doc. 214, Center for Advanced Computation, University of Illinois, Urbana, IL, 70 pp. Fluck, R.C., 1979. Energy productivity: a measure of energy utilization in agricultural systems. Agric. Syst., 4(1): 29--37. Fluck, R.C., 1980. Fundamentals of energy analysis for agriculture. In: Agricultural Energy. Vol. 1, Solar Energy and Livestock Production. Proc. ASAE National Energy
275 Symposium, 29 September-1 October 1980, Kansas City, MO. American Society of Agricultural Engineers, St. Joseph, MI, pp. 208--211. Fluck, R.C. and Baird, C.D., 1980. Agricultural Energetics. AVI, Westport, CT, 192 pp. Schipper, L. and Darmstadter, J., 1978. The logic of energy conservation. Tech. Rev., 80(3): 41--50. U.S. Bur. Census, 1978. Statistical Abstract of the United States. U.S. Bureau of the Census, Washington, DC, 1057 pp.