33
Emergy Evaluation of the Swedish Economy since the 1950s Peter Hagström and Per Olov Nilsson
ABSTRACT
The aim of this work was to analyze the change in resource basis of the Swedish economy from the 1950s until the present time and to establish indices for solar emergy per Swedish krona (sej/SEK) to be used in further studies. During the period 1956 to 2002, the population increased from 7.3 to 8.9 million. Total emergy use increased from 146.1 x 1021 to 369.5 x1021 solar emjoules per year, largely due to increasing imports of oil and uranium and an expanding service sector. Total imports increased from 85.6 x 1021 to 305.7 x 1021 sej/year and exports increased from 60.8 x 1021 to 262.5 x 1021 sej/year. The fraction of indigenous resources for the total economy decreased from 41.4% to 17.3% in emergy terms. Based on income statistics and consumer price indices the standard of living measured as gross national product per person, corrected for inflation, increased threefold whereas emergy use increased twofold, indicating an efficiency increase of 50% in solar emergy use per real wealth output. The renewable part of solar emergy use decreased from 31.0% to 12.2%
during the period, showing a substantial increase in dependence on non-renewable sources.
INTRODUCTION Scope of this study
Since 1974, scientists at the Swedish University of Agricultural Sciences have been involved in various programs and projects on biomass for energy. The Department of Bioenergy is trying to provide a scientifically based estimate of the theoretical and practical potential of biomass for energy in the Swedish energy supply system. Evaluation by methods based on standard economic theory are insufficient as standard economic theory and monetary values underestimate the importance of natural resources, in particular wood, peat, coal, oil, natural gas, hydro power and uranium (Hall et al. 1986, Chapter 2; Odum 1996, Chapter 4). Odum’s emergy evaluation theories were applied in an analysis of forest production and industries for the year 1988 (Doherty et al. 2002). This study are now extended by looking at the historical development, from fifty years ago until the present, as a background to a study on alternatives for the future. With the available resources it was not possible to study every year, so five years were selected. 1956 and 1972 were chosen, as there is a good study on energy balances in forestry and agriculture for these years (Genfors and Thyr 1976). For 1988, there is the aforementioned study by Doherty et al. (2002); 1996 was investigated by Lagerberg et al. (1999); and 2002 is the latest year with complete statistics for the Swedish economy.
Although the focus of these studies is on bioenergy, it is necessary to study Swedish economy in general as it is not possible to make a relevant analysis of any part of the economy without considering the next larger level of the hierarchical web (Odum 1996, Chapter 2). Another reason for studying the economy as a whole is that the emergy evaluation method may require that a solar emergy
to monetary unit index be established, that is a general value of how many basic energy units a monetary unit can buy. The main scope of this paper was to calculate such indices for the years 1956, 1972, 1988, 1996 and 2002 to be used in further bioenergy studies. A second aim was to analyze the change in resource basis of the Swedish economy for this period.
General Facts about Sweden
Sweden is one of the largest countries in Europe (447 760 km2), only Russia, Ukraine, France and Spain are larger, and extends 1600 kilometers from north to south, the same distance as Berlin to Moscow or New York to Minneapolis. In the north, winters are long, cold and snowbound but during the brief summers, there is twenty-four hours of daylight. In the south, winters are considerably milder and summers are longer.
Approximately half of Sweden’s land area is covered by forest. More than one third of the country is mountains, lakes and marshes. At present, less than a tenth of the total area, slightly less than 3 million hectares, is under cultivation. Sweden has a relatively favorable climate, considering its northerly location. However, the scale of agriculture varies greatly between the northern and southern parts of the country. The most extensive agricultural activity is found in central and southern Sweden.
The growing season in the far south is 240 days per year, whereas in the far north it is less than 120 days. The climate in central and southern Sweden is temperate. Annual precipitation during the last hundred years averaged 600 mm, but has increased to over 650 mm in the last decade.
In 1850, Sweden was a poor agrarian country with a population of about 3.4 million. Between 1870 and 1970, a rapid economic transformation occurred with an annual growth rate of 4% (compared with an annual average of less than 2% in the period 1970–2002). Behind this development was the successful exploitation of Sweden’s main natural resources: wood, iron ore and hydroelectric power.
An additional factor was dramatic improvements in transportation, notably the expansion of the railroad, road networks and ports. Also contributing to Sweden’s industrialization were improvements in agricultural productivity, which left laborers free to find jobs in the growing industrial sectors.
In the beginning of the 20th century, there was a gradual shift from staple industries toward manufacturing of higher value-added products. Demand from staple industries played a crucial role for the machinery and transportation equipment sectors. The need for efficient transportation in a country with long distances contributed to the success of the car manufacturers Volvo and Scania for example.
Behind the success of the electrical engineering group ASEA (now part of ABB) was the need to transmit energy from northern to southern Sweden. Economic growth was further stimulated by a number of epoch-making Swedish inventions and innovations. Many of today’s major Swedish manufacturing groups, including ASEA/ABB, Ericsson (telecommunications), SKF (industrial bearings), Sandvik (cemented carbide and steel) and Alfa Laval (processing equipment), still base their operations on ideas from the period before or around the beginning of the 1900s.
Sweden also benefited from not being drawn into the two world wars of the 20th century. In particular, the reconstruction of Europe after World War II enabled Swedish industry to quickly increase its share of foreign markets. Rapid economic growth also laid the groundwork for a household-oriented domestic goods and services sector as well as a rapidly expanding construction industry. More information on Swedish geography, economy and social and cultural development is published in fact sheets on the Internet by the Swedish Institute <http://www.si.se>.
Energy
Global industrialization has been driven by fossil fuels. Swedish development is an integrated and interdependent part of the economic development of the world as a whole. Historically, forests
thus, development has been heavily dependent on increasing imports of fossil fuels along with expanding use of the country’s hydropower potential.
In the beginning of the 1970s as much as 70% of Sweden’s total energy supply came as imported oil, mainly from the Arab states. After the attack on Israel and the simultaneous initiated oil embargo in 1973, it became obvious that Sweden had to change its energy supply situation. A substantial nuclear power capacity was built up in the 1970s and 1980s. However, public concerns about nuclear power (the risk of accidents such as Chernobyl in 1986 and the risk of the spread of radioactive materials due to terrorist attacks) and the environmental effects of fossil fuels (global warming and climatic change) created a political situation. As a result, the Swedish parliament decided to phase out nuclear power and decrease the emission of greenhouse gases according to the Kyoto protocol (adopted in Kyoto, Japan, 1997) and consequent decisions of the European Union. How this complicated equation will be resolved is not clear, but much hope is placed on more efficient energy use and renewable energy from biomass, wind power, sun collectors and solar cells.
METHODS
The emergy evaluation methods used in this paper were developed by H.T. Odum and are described in many of his publications and compiled in the book Environmental Accounting (Odum, 1996). Chapters 5 “Emergy Evaluation Procedure” and 10 “Emergy of States and Nations” are especially relevant for this study. Methods are also accurately described by Doherty et al. (2002).
Transformities (i.e. solar emergy units per unit actual energy, mass or money) for various processes are given in these references.
Primary input data from national statistics of indigenous production, import and export of goods and services (Geological Survey of Sweden, 2003; Statistics Sweden, 1959, 1975, http://www.scb.se) were compiled in a spreadsheet. The emergy value of each item was then calculated by multiplying the quantity or monetary value by their respective transformity. These emergy values were then added in order to calculate the total emergy use for each year and the emergy in import and export of goods and services for each year.
The calculated emergy values were used to calculate the fraction of indigenous resources used from the total national economy for each year. Furthermore, the emergy use was compared with national economic statistics to evaluate the change in resource efficiency in the national economy for each respective year. The use of renewable resources versus non-renewable was also evaluated.
RESULTS
The indigenous resource base of Sweden includes the renewable resources of sunlight, kinetic wind energy, rainfall, stream flow and the energies from a portion of the Baltic Sea, including tides and surface winds, driving waves and currents. Major indigenous renewable production systems are forestry, agriculture, fishing and hydroelectricity generation. Sweden has an active and prosperous mineral and metal ore extractive industry, including iron ores, copper, lead, zinc, and other mineral rocks. The indigenous environmental and meteorological inputs are presented in Tables A.1 and A.2.
Imported and exported goods, fuels and human services are compiled in Tables A.3 and A.4. These data are summarized and supplemented in Table 1. Based on these evaluations, overview indices of annual emergy-use, origin and economic and demographic relations were calculated (Table 2).
During the period 1956 to 2002, the population increased from 7.3 to 8.9 million. The total emergy use, U, increased from 146.1 x 1021 to 369.5 x 1021 solar emjoules per year, mainly due to increasing imports of oil and uranium, a rapidly increasing public service sector (mainly health care, education and social services), and an increase in service input to goods production. As this production becomes increasingly advanced and international, more services (i.e. research and development, marketing, transportation etc.) are needed to ensure the smooth functioning of production and sales
Table 1. Summary of major solar emergy flows and market economic monetary flows for Sweden in 1956, 1972, 1988, 1996 and 2002. Compiled from Tables A.1–A.4 in the Table Annex
1) Renewable environmental sources (R) are corrected for double counting of byproduct solar emergy by summing all independent, over-land contributions and subtracting the coupled flows since the annual global solar emergy budget was used to derive solar transformities for each source (see Doherty et al. 2002, Tables 1, 2 and 4 for details): sun + wind + stream hydro-geopotential energy + chemical potential energy in rain + net uplift – (sun + wind) = (270.0 + 96.6 + 43.0) x 1020 sej/yr = 409.6 x 1020 sej/year.
Variable Item 1956 1972 1988 1996 2002
R
N
F G I P2I
E P1E
B X P2
P1
U
Renewable sources1) [1020 sej/year]
Sun Wind over land Evapo-transpired rain Hydro-geopotential Net land uplift Waves received Tides
Non-renewable sources within Sweden (mineral and metal ores) [1020 sej/year]
N1 Refined within the country N2 Export of unprocessed raw materials Imported fuels (fossil fuels, uranium) [1020 sej/year]
Imported goods, minerals, fertilizers [1020 sej/year]
Money paid for imports [109 SEK/year]
Solar emergy value of service in imports [1020 sej/year]
Money received for exports [109 SEK/year]
Solar emergy value of service in exports [1020 sej/year]
Exports transformed, upgraded within country [1020 sej/year]
Gross National Product [109 SEK/year]
European trade partner’s solar emergy/SEK index [109 sej/SEK]
Sweden’s solar emergy/SEK index (U / GNP) [109 sej/SEK]
Total solar emergy2) [1020 sej/year]
452.4 10.5 47.6 96.6 270.0 43.0 42.8 1.1
301.0 152.2 148.8 328.1 101.2 13.2 427.2 13.0 343.2 116.4 55.2 3 240 2 642 1 461
452.4 10.5 47.6 96.6 270.0 43.0 42.8 1.1
508.2 266.8 241.4 834.5 199.9 46.2 673.6 49.3 587.1 349.0 203.8 1 458 1 188 2 427
452.4 10.5 47.6 96.6 270.0 43.0 42.8 1.1
284.2 132.6 151.6 916.1 245.9 341.4 1 051.4 359.7 903.2 618.0 1 114.5 308 251 2 798
452.4 10.5 47.6 96.6 270.0 43.0 42.8 1.1
305.9 175.4 130.5 1 081.3 277.1 568.7 1 237.4 688.3 1221.1 771.1 1 817.2 218 177 3 224
452.4 10.5 47.6 96.6 270.0 43.0 42.8 1.1
307.9 185.5 122.4 999.3 371.8 870.6 1 686.3 1 012.4 1 598.9 903.5 2 340.0 194 158 3 695
Physical energies in surrounding seas were calculated similarly: sun + wind + waves + tide – (sun + wind + tide) = 42.8 x 1020 sej/year. R-total = land based emergy + sea based emergy = (409.6 + 42.8) x 1020 sej/yr = 452.4 x 1020 sej/year.
2) U = N1 + R + F + G + P2I
systems. The tendencies for the distribution of emergy for imports and exports for the different years can be seen in Figure 1.
From 1956 to 2002, total imports increased from 856 x 1020 to 3057 x 1020 sej/year and exports increased from 608 x 1020 to 2625 x 1020 sej/year (Figure 2). Total indigenous renewable production increased slightly from 696 x 1020 sej/year to 902 x 1020 sej/year, whereas the total indigenous non-renewable sources was almost constant (about 300 x 1020 sej/year), except in 1972 when it was 508 x 1020 sej/year (due to a high production of iron ore). The emergy flow from renewable sources was assumed constant for the different years (452 x 1020 sej/year). The percentage of indigenous resources of the total economy decreased from 41.4% to 17.3% in terms of emergy use (see Table 2).
Table 2. Overview indices of annual solar emergy-use, origin and economic and demographic relations for Sweden in 1956, 1972, 1988, 1996 and 2002
Name of index Derivation 1956 1972 1988 1996 2002
Flow of imported solar emergy [1020 sej/year]
Economic component [1020 sej/year]
Total exported solar emergy [1020 sej/year]
% Locally renewable (free) Economic/environment ratio Ratio of imports to exports Export to imports
Net contribution due to trade (imports minus exports) [1020 sej/year]
% of solar emergy-use purchased
% of solar emergy-use derived from home sources Solar emergy-use per unit area [109 sej/m2] Population [106 inhabitants]
Solar emergy-use per person [1016 sej/person]
Renewable carrying capacity at present living standard [106 people]
Carrying capacity using local resorces [106 people]
Fraction electric1) Fraction fossil fuels2)
Fuel-use per person [1015 sej/person]
F+G+P2I U-R N2+B+P1E R / U (U - R) / R
(F+G+P2I) / (N2+B+P1E) (N2+B+P1E) / (F+G+P2I) (F+G+P2I ) - (N2+B+P1E)
(F+G+P2I) / U (N1+R) / U U / area
U / population (R/U)*(population)
[(R+N)/U]*(population) (electricity-use) / U (fuel-use) / U fuel-use / population
856.5 1 008.7 608.5 31.0 2.23 1.41 0.71 248.0
58.6 41.4 355.5 7.339 1.99 2.27
3.78 0.05 0.22 4.47
1 707.9 1 974.7 1 177.4 18.6 4.36 1.45 0.69 530.5
70.4 29.6 590.5 8.129 2.99 1.52
3.22 0.07 0.32 10.00
2 213.4 2 346.0 1 672.7 16.2 5.19 1.32 0.76 540.6
79.1 20.9 680.9 8.459 3.31 1.37
2.23 0.18 0.14 7.22
2 595.8 2 771.2 2 122.7 14.0 6.13 1.22 0.82 473.1
80.5 19.5 784.3 8.844 3.64 1.24
2.08 0.16 0.14 8.19
3 057.4 3 242.9 2 624.8 12.2 7.17 1.16 0.86 432.6
82.7 17.3 899.1 8.941 4.13 1.09
1.84 0.14 0.10 7.45
1) Solar emergy for electricity generation estimated from solar transformity including human services, 0.2 x 106 sej/J (Odum, 1996).
2) Emergy values for imported fuels (F) were estimated using solar transformities from Odum (1996) which include associated human services (coal 40 000 sej/J; natural gas 48 000 sej/J; crude oil 54 000 sej/J; refined petroleum 66 000 sej/J) so that the full cost of these primary sources were considered.
Emergy per monetary unit ratio
The results of the calculations of the buying power of a monetary unit – the emergy per monetary unit index – are shown in Table 1 (indices P1 and P2). Index P1 decreased from 2642 x 109 sej/SEK in 1956 to 158 x 109 sej/SEK in 2002. According to Odum (1996, p. 312), this decrease was partly due to inflation and partly to economic development (which increases money circulation for the same resource use), and to some extent due to increasing efficiency in resource use.
Based on income statistics and consumer price indices, the standard of living measured as gross national product per person (GNP), corrected for inflation, increased threefold whereas emergy use only increased twofold, indicating an efficiency increase of 50% in solar emergy use per real wealth output (Table 3). This increase was partly due to more efficient resource use and partly to industrialization (fuels of relatively low transformity replaced human and draught animal energy of high transformities).
As economic expansion was driven by fossil fuels, the dependence on non-renewable resources increased considerably during the period and the renewable part of solar emergy use decreased from 31.0% to 12.2% (see Table 2, index R/U).
igure 1. Distribution of emergy flows for imports and exports in Sweden in 1956, 1972, 1988, 1996 and 2002.
Imports
0 200 400 600 800 1 000 1 200 1 400 1 600 1 800
Fossil fuels Electricity and uranium for nuclear
power generation
Fertilizers, food, fodder and fish
Metals and goods Services
Emergy (1E20 sej/year)
1956
1972 1988 1996 2002
Exports
0 200 400 600 800 1 000 1 200 1 400 1 600 1 800
Fossil fuels Electricity Wood and
forest industry products
Food and fodder from agriculture and
stockraising
Metals, machines and
other goods
Services
Emergy (1E20 sej/year)
1956
1972 1988 1996 2002
F
0 500 1 000 1 500 2 000 2 500 3 000 3 500
Renewable sources Total indigenous nonrenewable
sources
Total indigenous renewable production
Total imports Total exports
Emergy (1E20 sej/year)
1956
1972 1988 1996 2002
Figure 2. Emergy flows in Sweden in 1956, 1972, 1988, 1996 and 2002.
Table 3. Relative standard of living in monetary terms and relative solar emergy per person. Base year
1956 1972 1988 1996 2002
1956
Note
1 ross national product (GNP) per e index (year 1956 = 100)
per capita a, base year 1956
7 517 100 7
1.99 1.00
25 065 194 12
2.99 1.50
131 755 725 18
3.31 1.66
205 455 1 051 1
3.65 1.83
261 716 1 120 2
4.13 2.08 2
3 4 5 6
G
capita [SEK]
Consumer pric
Index weighted GNP per capita [SEK]
Relative "standard of living" in monetary terms
Solar emergy use [1016 sej/capita]
Relative sej/capit
517 1.00
920 1.72
173 2.42
9 549 2.60
3 368 3.11
al product (X) divided by population.
se).
.
ta for the topical year and index weighted GNP per ed by population.
er capita for the topical year and solar emergy use per capita for
1 Gross nation
2 Data taken from Statistics Sweden (http://www.scb.
3 GNP per capita divided by (Consumer price index / 100)
4 Calculated as the quotient of index weighted GNP per capi capita for 1956. 1956 = 1.00.
5 Total solar emergy (U) divid
6 Calculated as the quotient of solar emergy use p 1956. 1956 = 1.00.
Energy
Sweden’s energy supply for the years studied is shown in Figure 3. In 2002, Sweden’s energy supply c
s an important role in Sweden’s energy supply. In 2002, hydropower and nuclear
960s and 1970s from abo
ports of fossil fuels, mainly oil and oil products, increased markedly from 156 TWh
en in Tables A
e total energy use (indigenous production plus imports minus exports) increased from 397.2 x
etals and minerals
The percentage of mined iron ore in relation to the total indigenous mined production was between
onsisted of 335 TWh of fuels and 141 TWh of electricity. About 70% of the fuels were imported (208 TWh of oil and natural gas and 29 TWh of coal and coke). The remaining 30% (98 TWh) came from indigenous sources, mainly wood. Half of the oil products were used in the transport sector; the other half was equally used by the residential and service sectors and industry (Swedish Energy Agency, 2003).
Electricity play
power together accounted for 91.7% of total power production. The remaining 8.3% was generated by condensing power, gas turbines, industrial back-pressure power, wind power and combined heat and power (CHP) plants, which produce both electricity and hot water for district heating (Swedish Energy Agency, 2003). The nuclear power plants are powered by imported fuel.
Although Sweden does have domestic uranium deposits, they are mostly low grade and not considered economical. Earlier mining plans also met strong opposition from environmentalists.
The capacity of hydroelectric power production in Sweden expanded in the 1
ut 25 to about 65 TWh/year. However, production varies according to the weather. In the dry year of 1996, production was down to 52 TWh, but in 2000 and 2001, it was as high as 79 TWh/year.
Most hydropower comes from nine rivers in the northern half of Sweden. Expansion of hydropower capacity is restricted according to a decision by the Swedish parliament. The four unexploited rivers in the northern part of the country will remain untouched for environmental reasons. As shown in Table A.2, the indigenous production of hydroelectricity increased from 69.3 x 1020 sej in 1956 to 203.6 x 1020 sej in 1988.
Up to 1973, the im
in 1956 to 349 TWh in 1972. Subsequently, the nuclear power sector expanded rapidly andimported fossil fuels were largely replaced by electricity. However, in 2002, the total import of fossil fuels (666.6 x 1020 sej) was more than twice the import of uranium (274.6 x 1020 sej) in emergy terms.
The import of crude petroleum was much higher than domestic need, which can be se .3 and A.4 (refined fuels were exported all the years studied). Imports of energy increased from 328.1 x 1020 sej in 1956 to 999.3 x 1020 sej in 2002. During the same period, export of energy (mainly refined fuels) increased from 0.4 x 1020 sej to 343.4 x 1020 sej. This was due to investments in refinery capacity during the 1970’s and 1980’s, in order to increase the flexibility in choice of oil suppliers.
Th
1020 sej in 1956 to 936.2 x 1020 sej in 1996, but by 2002, the total energy use had decreased to 851.6 x 1020 sej. The total import of energy was at a maximum in 1996 (1081.3 x 1020 sej), but total exports had increased to 343.4 x 1020 sej by 2002.
M
60% and 70% during the whole period in terms of emergy. The second most important mined fraction was sedimentary material (mainly limestone and dolomite), the percentage of this fraction in relation to the total indigenous mined production fluctuated between 16% and 30% during the period in terms of emergy. The total indigenous mined production reached a maximum in 1972 (508 x1020 sej), whereas during the other years studied, the total indigenous mined production was about 300 x 1020 sej (see Table A.2).
Figure 3. The contribution of various fuels to the Swedish energy budget for the selected years.
Imported metals and alloys mainly consisted of steel. The quantity of imported metals and alloys increased from 18.3 x 1020 sej in 1956 to 62.2 x 1020 sej in 2002, as shown in Table A.3.
From 1956 to 1988, iron ore was the most important export commodity in emergy terms. In 1956, the percentage of exported iron ore (148.8 x 1020 sej) in relation to the total export (269.5 x 1020 sej), excluding service, was 55.2%, after which it declined steadily to 11.9% (122.4 x 1020 sej and 1031.2 x 1020 sej respectively) in 2002. During the same time, the export of steel products increased steadily, and in 2002 the percentage of exported steel products (81.0 x 1020 sej) in relation to the total export of steel products and iron ore (203.5 x 1020 sej) was 39.8% (see Table A.4). This was due to an increasing indigenous refinement of the iron ore to steel products.
Forestry and Forest Products Industry
During the period, the forest harvest increased from 143 x 1020 to 231 x 1020 sej/year and increased its share of the indigenous renewable production from 21% to 26% in terms of emergy.
In monetary terms, paper production now accounts for more than half of both value-added and export value in Swedish forest products industry, and is the segment that has expanded the most for several decades, as new pulp capacity has been integrated with paper production. Market pulp production capacity has remained largely unchanged whereas sawmill capacity has risen.
The Swedish forest products industry is strongly export-oriented. In 2002, about 85% of paper and market pulp output was exported; the corresponding figure for sawn timber products was 75%.
Western Europe is the dominant market.
Exports of wood and forest industry products have constantly increased in monetary as well as in emergy terms (Table 4). In 1956, about one third of the export income came from wood in exchange for almost 80% of the exported emergy. By 2002, the relative export income from these products had decreased to about 8% of total export value in exchange for one third of the country’s exported emergy. Exported emergy from wood and wood products in relation to total emergy use remained constant at around 6–8%.
Food
In spite of its limited arable land and climatic disadvantages in comparison with many other countries, Sweden’s agricultural production is only slightly less than the level of consumption.
The total indigenous production of food was in principal at the same level during the period. Maximum production was in 1988 (513.8 x 1020 sej), and after that, there was a slight decrease to 475.5 x 1020 sej in 2002. However, the indigenous fishing industry showed a maximum production in 1996 (63.6 x1020 sej), see Table A.2.
The import of food commodities increased during the period, from 21.9 x 1020 sej to 78.0 x 1020 sej (see Table A.3). However, export increased markedly, from 9.3 x 1020 sej in 1956 to 57.0 x1020 sej in 2002 (see Table A.4). Hence, total Swedish food consumption (indigenous production plus imports minus exports) has been relatively stable at around 500 x 1020 sej, with a modest increase mainly reflecting population growth.
In 2002, the nutritional value per person per day was approximately 12.2 kJ. Bread and grain products, meat and edible fats accounted for half of the calorific intake in Sweden. In weight, animal products are the smaller part, but in emergy terms, they dominate because of high transformities. In 1956, the percentage of livestock and dairy in relation to the total indigenous food production (agricultural crops, livestock, dairy products and fish) was 73% in emergy terms; however, since the
Table 4. Export of wood and forest industry products in monetary and in emergy terms
Note 1956 1972 1988 1996 2002
1 2 3 4 5 6
Money received for exports [109 SEK/year]
Money received from exports of wood and forest industry products [109 SEK/year]
% of export income
Emergy in exports upgraded within the country [1020 sej/year]
Emergy in exports of wood and forest industry products [1020 sej/year]
% of exported emergy
13.0 4.0 31.3%
116.4 91.0 78.2%
49.3 9.3 18.9%
349.0 176.2 50.5%
359.7 58.8 16.3%
618.0 219.1 35.5%
688.3 62.0 9.0%
771.1 240.2 31.2%
1 012.4 78.2 7.7%
903.5 289.2 32.0%
1 Data taken from Statistics Sweden (1959, 1975, http://www.scb.se).
2 Data taken from The National Board of Private Forestry (1962) and National Board of Forestry (1976, 1991, 1998, 2003).
3 Money received from exports of wood and forest industry products divided by money received for exports (E).
4 Specified in note 9, Table 1.
5 Sawlogs, roundwood, sawn wood, board, chemical and mechanical pulp and paper products included (solar emergy values for each item specified in Table A.4.).
6
1980s it has been about 65% (see Table A.2).
Machines and vehicles
The import of vehicles increased from 9.9 x 1020 sej in 1956 to 25.1 x 1020 sej in 2002 (see Table A.3). During the same time, the export of vehicles increased from 2.6 x 1020 sej to 40.8 x 1020 sej, and the export of machines increased from 8.5 x 1020 sej to 95.2 x 1020 sej (see Table A.4). Thus, the import of vehicles was approximately as large as the export of vehicles and machines in 1956, but in 2002, the export of vehicles and machines was more than five times greater than the import of vehicles in emergy terms.
Other imports and exports
Wool and cotton were important import commodities during the 1950s and 25.6 x 1020 sej was imported in 1956. This quantity declined to 6.1 x 1020 sej in 1996, but increased to 14.5 x 1020 sej in 2002 (see Table A.3).
During the whole period, fertilizers were important commodities, as shown in Table A.3.
Imports reached a maximum in 1988 (27.8 x 1020 sej) but declined to 17.5 x 1020 sej by 2002.
The import of plastics increased markedly during the period, from 0.7 x 1020 sej in 1956 to 39.0 x 1020 sej in 2002 (see Table A.3).
Commodities specified as other imported goods in Table A.3 were animal hides, clothing, cotton fabrics, synthetic fibers, tires, chassis and other car parts. The import of these commodities increased steadily during the whole period, from 5.8 x 1020 sej in 1956 to 53.6 x 1020 sej in 2002.
Commodities specified as other exported goods in Table A.4 were ADP machines, ADP parts, telecommunications equipment, televisions and car parts. The export of these commodities also increased steadily during the whole period, from 1.7 x 1020 sej in 1956 to 41.3 x 1020 sej in 2002.
DISCUSSION
Odum used the concepts of emergy and transformity to develop a tool for evaluating systems where both the work of nature and that of humans in the generation of products and services were taken into account. The principles are logical and easy to understand, but some difficulties arise when applied in a study like this one.
A transformity can be looked upon as the physical cost, in emergy terms, for a unit of a service or commodity, expressed in terms of actual energy or mass. Like monetary costs, the transformities change with technological development. For example, the transformity for cutting a log with a handsaw and transporting it from the forest to the roadside with draught animals, as the work was done in 1956, was probably higher than the transformity for doing the same operations with a highly mechanized system in 2002. This study indicated that on average the transformities for the total Swedish economy might be 33% lower today than fifty years ago. Table 3 indicates that “real wealth”
per capita has increased three times for twice the resource input. The efficiency increase is partly due to technological development but presumably is more dependent on changes in the types of energy used: transformities for fossil fuels and electricity are considerably lower than transformities for draught animal and humans. Transformities, like monetary costs, are also dependent on the scale of the economy.
A practical problem in emergy evaluation is that it is time consuming to derive all the different transformities. Hence, the same transformities were used for all the years studied. The same
data was also used for natural renewable resources for all years, though climatic conditions, for example rainfall, differ among the years. In the latter case, the differences did not influence the result, as they were a small part of the total emergy-use.
Due to the need for extensive analysis, another difficulty is to find a proper estimate of the emergy/money ratio for other countries. This index has to be known as it influences the calculation of the emergy/money index for the country of interest, or what is termed by economists ”terms of trade”
between countries. In this study, the value given by Odum in Doherty et al. (2002) provided a starting point, which was 2.0 x 1012 sej/USD for the year 1988. The conversion rate of 6.5 SEK/USD in 1988, which is used in that report, gave 3.08 x 1011 sej/SEK. This value gave a calculated index for Sweden in 1988 of 2.51 x 1011 sej/SEK, which means that Sweden received more emergy per SEK in imports than was sent out per SEK in exports. The same relations in terms of trade were assumed, without further analysis, for all years.
Doherty et al. (2002) calculated the estimates of sej/SEK indices for 1988, and Lagerberg et al. (1999) calculated the estimates for 1996. These estimates differ somewhat from the sej/SEK indices shown in this article, for instance, the sej/SEK index for 1996, shown by Lagerberg et al., was 2.14 x 1011 compared to the 1.77 x 1011 calculated in this work. The discrepancies were mainly due to the different data references and transformities used for some items. Lagerberg et al. working with the data available at that time, calculated a higher value for total emergy use, 3598 x 1020 sej compared to the current 3224 x 1020 sej, and a lower value for GNP, 1678 x 109 SEK compared to 1817 x 109 SEK.
Since then, the GNP has been adjusted upwards by the authority for Statistics Sweden. Additionally, data from Geological Survey of Sweden (SGU) instead of Statistics Sweden was used in this work as reference for mined quantities of ores, metals and minerals, as SGU’s statistics for these items are more accurate.
In this study, some commodities had a maximum production and import in 1988 or 1996. This was also determined for example for the total energy use, which was at a maximum in 1996, and the total food consumption, which was at a maximum in 1988. However, differences for specific commodities may only show variations in the state of the market for the years studied and not be evidence of long-term trends. Some general trends have however, been indicated, for example, the renewable part of solar emergy use has steadily decreased since the 1950s, and was only 12.2% in 2002.
In 2002, electricity and fossil fuels accounted for about 10% of GNP but for as much as 40%
of the total emergy use (see Table 2). Human services are the other dominant and rapidly growing part of total emergy use in the national economy. This is reflected in Table A.4, where an increase from 342 x 1020 sej in 1956 to 1599 x 1020 sej in 2002 regarding services in exports is shown. Thus, the share of services in relation to total exports increased from about 55% to 60% during the period.
So far, a growing service sector seems to have been beneficial to the economic system as a whole, however, lately there are signs that this effect is declining. As shown in Table 3, economic development is built on bringing in more resources, i.e. increasing emergy supply, and using these resources more efficiently, i.e. lowering transformities. One question for the future is if we have reached the point where total emergy use is peaking, and the only way of improving is to increase efficiency with the available resources, i.e. lower transformities?
REFERENCES
Doherty, S., Nilsson, P.O. and Odum, H.T. 2002. Emergy Evaluation of Forest Production and Industries in Sweden. Swedish University of Agricultural Sciences, Department of Bioenergy, Report No. 1. Uppsala, Sweden.
Genfors, W. and Thyr, B. 1976. Dataunderlag för energibalansberäkningar inom skogsbruket.
(English summary: Basic data for energy-balance evaluations in forestry). Royal College of Forestry, Department of Operational efficiency. Research Notes No. 96. Garpenberg, Sweden.
Geological Survey of Sweden (SGU). 2003. Statistics of the Swedish Mining Industry 2002.
[Bergverksstatistik 2002.] Per. publ. 2003:1. Sweden (in Swedish).
Hall, C.A.S., Cleveland, C.J. and Kaufmann, R. 1986. Energy and resource quality: the ecology of the economic process. New York: John Wiley & Sons. ISBN 0-471-08790-4.
Lagerberg, C., Doherty, S.J. and Nilsson, P.O. 1999. Evaluation of the Resource Efficiency and Sustainability of the Swedish Economy Using Emergy-Based Indices. In Lagerberg, C. 1999.
Emergy Analysis of the Resource Use in Greenhouse Crop Production and of the Resource Basis of the Swedish Economy. Swedish University of Agricultural Sciences, Acta Universitatis Agriculturae Sueciae, Agraria 191. Alnarp, Sweden.
Odum, H.T. 1996. Environmental Accounting: Emergy and Environmental Decision Making. John Wiley and Sons. New York, U.S.A.
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[Skogsstatistisk årsbok 1974.] Jönköping, Sweden (in Swedish).
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[Skogsstatistisk årsbok 1991.] Jönköping, Sweden (in Swedish).
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TABLE ANNEX
Table A.1. The physical energy, transformities and the solar emergy received over land and over Sweden’s share of the Baltic Sea. From Doherty et al. 2002, Table 2
E [J] Transformity
[sej/J]
Emergy [1020 sej]
Physical energy received over land Solar insolation Wind, kinetic energy Evapo-transpired rain Hydro-geopotential energy Net uplift Physical energy over the Baltic Sea Solar insolation Surface wind absorbed Rain, chemical Runoff, chemical Tidal energy Waves received
1.05E+21 3.17E+18 5.31E+17 7.20E+17 1.33E+11
5.68E+20 1.98E+18 6.32E+16 1.40E+17 6.56E+15 1.40E+17
1.00E+00 1.50E+03 1.82E+04 3.75E+04 3.23E+10
1.00E+00 1.50E+03 1.82E+04 4.85E+04 1.69E+04 3.06E+04
10.50 47.55 96.64 270.00 43.00
5.68 29.70 11.50 67.90 1.11 42.77
