NOTE: RAPE SEED OIL FOR TRANSPORT 2:

AGRICULTURE AND ENERGY
THE ENERGY PURPOSE MARKET FOR RAPE SEED OIL

Jacob Bugge, 9/11 2000. Translation August 2001

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SUMMARY:

From a general consideration of sustainability, it would be natural for agriculture to contribute a significant part of the country's energy supply and to have a positive energy balance as an industry.

Today, agriculture has a gross energy consumption which in fact is more than twice the existing energy production from agricultural biomass.

There is a considerable difference in the utility value and coefficient of utilisation. In this context, engine fuels comprise a special class, because an extensive utilisation of electricity and hydrogen for these purposes is still in a more remote future.

The substitution principle defined in this note can be used to optimise the use of the individual renewable energy sources so each of them makes the most valuable contribution and so they all put together cover the whole spectrum of energy uses.

The cold pressed rape seed oil presents the energetically and environmentally best alternative to fossil diesel with a strongly positive energy and CO₂ balance. The use of rape seed oil for transport can substitute the agricultural industry's own fuel consumption, and it is an obvious subject of tax reductions.

With conventional cultivation of winter rape, the total fuel consumption of the Danish agricultural industry could be covered on a good 10% of the agricultural area along with covering 20% of the protein fodder consumption and 81% of agriculture's total gross energy consumption.

Utilisation of the absolute area potential of 20% of the agricultural area corresponds to a production equalling ca. 180% of the agricultural fuel consumption, 35% of the protein fodder consumption, and 180% of the gross energy consumption.

Any increase in the rape seed oil production, non food as well as food oil, conventional as well as organic, will contribute to the potential of rape seed oil for energy purposes, especially engine fuel in connexion with tax reductions.

CONTENTS:

Summary

1. Agriculture and energy

1.1. Energy forms and utility values
1.2. Liquid biofuels
1.3. The potential for rape cultivation
1.4. The substitution principle

2. The market for rape seed oil for energy purposes

3. References and key figures

1. AGRICULTURE AND ENERGY:

The active productive agricultural area covers almost 2/3 of the total land area of Denmark; in 1998 it was 62% with 2,672 million ha out of 4,308 million ha [1].

At the same time, agriculture and forestry are the only production industries which are directly based upon solar energy. This is done through production of various forms of biomass which can be used for food, directly and indirectly in the form of fodder, and for energy.

From a general consideration of sustainability, it would therefore be natural for agriculture to contribute a significant part of the country's energy supply.

Oppositely, it seems unnatural if agriculture, and especially organic agriculture, can only be carried on with an effective consumption of fossil energy, in other words with a negative energy balance. However, this is presently the case.

Under the present circumstances, Danish agriculture has in fact a gross energy consumption which is more than twice the existing energy production from agricultural biomass. Thus the gross energy consumption at the farms, in other words excluding the energy consumption for production of fertilizers and pesticides, is summed up to 33,413 PJ which is 12,5 GJ/ha [1]. The energy consumption for nitrogenous fertilizers alone amounted to at least 10 PJ in 1998 [1], [4]; inclusion of this amount would raise the agricultural gross energy consumption by 30%. The corresponding actual energy production from biomass amounted to 6,0 GJ/ha, totalling 16,029 PJ; this comprised 13,359 PJ from straw and 2,670 PJ from biogas [2].

1.1. ENERGY FORMS AND UTILITY VALUE:

Different forms of energy differ significantly in terms of utility value and coefficient of utility. Therefore, an optimum sustainable energy use based upon renewable energy requires that the prospects of the individual renewable energy sources are utilised so that each of them yields the most valuable contribution, and so that they all put together cover the whole spectrum of energy uses.

The simplest and least valuable use of energy is heat production. Electricity is a more versatile and hence more valuable energy form which is highly efficient for stationary purposes. Thus CHP gives a better utilisation of the resources than heat production alone.

In this connexion, engine fuels comprise a special class because it is actually impossible to replace them. An extensive utilisation of electricity and hydrogen for these purposes still belongs to a more remote future.

The solid biofuels such as straw can be used for heat production in burners right away. With more advanced plants they can fuel CHP; however, the installation price is still a limiting factor. With this, the solid biofuels naturally cover heat, and to a certain extent, CHP.

With present technology, biogas can be used directly in both heat plants and CHP plants. In addition, it can be used for mobile purposes, but this requires changes in the engine construction, and the fuel tank is relatively voluminous. Therefore, biogas is most suitable for CHP.

Liquid biofuels such as rape seed oil, biodiesel and ethanol are the most versatile fuels because they can easily be used for heat production, CHP, and mobile purposes.

The negative energy balance in agriculture especially applies to engine fuels because the consumption has no notable production counterpart.

The diesel consumption for agricultural machinery amounted to 283 million litres in 1998 [1]. This corresponds to an average of ca. 105 litres diesel/ha; it is assumed that this figure applies to both conventional and organic agriculture. With a gross energy content of 39,5 MJ/l [3], the diesel consumption amounts to 11,179 PT, in other words a good 33% of the agricultural gross energy consumption.

Therefore, as an element in an optimum sustainable energy use there is every reason to make biomass-based production of engine fuels a particular area of effort.

1.2. LIQUID BIOFUELS:

Cold pressed rape seed oil can substitute diesel after a minor modification of the engine. The oil presents no fire and health hazards, and it is unpolluting. The oil is pressed in an unexpensive plant with a low energy consumption [3], and the whole production can take place at the individual farm so the fodder cakes can be used on site or be sold locally.

Biodiesel can substitute fossil diesel right away. However, biodiesel presents health and fire hazards in itself, and it is polluting. The pressing and the following esterisation comprise an industrial process with a high energy consumption which requires an expensive, centralised production plant [3], [4].

Consequently, the cold pressed rape seed oil presents the energetically and environmentally best alternative to fossil diesel. The energy and CO₂ balance for the rape crop is also strongly positive [5].

Ethanol cannot replace gasoline, but it can be used as an additive. The gasoline still presents hazards to health and environment, and it is highly flammable. The value of ethanol could especially be environmental as substitution for MTBE, but the use can remain limited by other environmental rules because ethanol increases gasoline evaporation. As for biodiesel an industrial production process with high energy consumption is required [4].

As it appears, the cold pressed rape seed oil as engine fuel is in a class of its own. The best energy use of rape seed oil is therefore mobile purposes.

Apart from the use of rape seed oil as engine fuel, the other parts of the crop, namely the rape cakes and the rape straw, hold a great potential.

1.3. THE POTENTIAL FOR RAPE CULTIVATION:

There is a great unused potential for rape cultivation in Danish agriculture. Under the favourable condition up to 1991 the production area grew to 280.000 ha which is 10,5% of the total agricultural area of 2.672.000 ha [1].

With conventional cultivation, this corresponds to a production of 840.000 tons of rape seed. Cold pressing yields 1/3 oil, i.e. 280.000 tons, and 2/3 fodder cake, i.e. 560.000 tons; in addition to this about 1,1 million tons of straw are produced [3].

An oil production of 280.000 tons corresponds to 304 million litres rape seed oil equalling 289 million litres of diesel, more than the total agricultural fuel consumption. As mentioned above this amounts to 11,2 TJ, a good 33% of the agricultural gross energy consumption.

A fodder cake production of 560.000 tons equals 623 million fodder units (FU), 20% of the total consumption of protein fodder of 3131 million FU and more than 12 times the total domestic production of 398 million FU [1], [6]. The total energy content is 10,8 TJ.

A straw production of 1,1 million tons equal a gross energy content of 15,9 TJ which corresponds to the entire present energy production from biomass, 48% of the total agricultural gross energy consumption of 33,4 TJ and more than 6 times the consumption of straw for energy purposes at the farms of 158.000 tons [1]. Along with the rape seed oil it corresponds to 81% of the agricultural gross energy consumption.

The actual gross energy consumption for rape cultivation including fertilizers and pesticides corresponds to the general average in farming excluding fertilizers and pesticides [5]. An increase in the rape production area will therefore not increase the total gross energy consumption in agriculture.

So conventional cultivation of winter rape in a good 10% of the agricultural area could cover the total agricultural fuel consumption along with 20% of the protein fodder consumption and 81% of the total agricultural gross energy consumption. Along with the present biomass production, this could actually create a positive energy balance for agriculture.

As a comparison, it is worth mentioning that the agricultural engine fuel of the past, oat, took up 380.955 ha in 1938, just under 12% of the then agricultural area of 3.268.000 ha and just under 28% of the corn-and-legumes area of 1.377.000 ha [7]. By far the greater part of this area, probably ca. 355.000 ha, was used for fodder; thus the oat area in 1990 - 1992 was only 26.000 ha [1]. It should be noted that both grain and straw were used for fodder. In addition to this, the feeding of horses took up ca. 460.000 ha with root crops, grass, and hay [7], [8]. See also the key figures for horse feedstuffs at the end of this note.

All together, the feeding of horses has taken up ca. 815.000 ha, 25% of the total agricultural area.

This means that the present agricultural engine fuel need can be covered by rape seed oil from 40% of the area which was used for similar purposes in the 1930's.

It is worth mentioning that at the same time mechanisation has replaced most of the manual labour, and there is a considerable parallel production of rape cakes and rape straw.

With a total crop rotation area of ca. 2.500.000 ha, the maximum area potential of rape cultivation is ca. 500.000 ha [3]. This is stil only 80% of the area taken up by the feeding of draught horses in the 1930's. The corresponding rape production could cover ca. 180% of the agricultural fuel consumption, 35% of the protein fodder production, and 145% of the gross energy consumption.

1.4. THE SUBSTITUTION PRINCIPLE:

It would seem obvious to cover the agricultural industry's own energy consumption directly through biomass. As an element in this, the agricultural machinery could be run on rape seed oil. This would also give immediate environmental improvements in agriculture. Among other things, spillage and leaking of fuel would be harmless. In Germany, tractors run on rape seed oil, primarily because of environmental considerations.

However, the same overall effect would result from the use of rape seed oil for road transport where the total fuel consumption of 4.411 million litres is 15 times greater [9].

This corresponds to using the straw centrally instead of at the individual farm. This an be done with the same utility value of the straw if a central CHP plant replaces a CHP plant at the farm or if the straw is used in a district heating plant instead of a straw burner. If a centralised CHP plant replaces a straw burner at the farm, the utility value is improved.

The substitution principle is defined as follows:

A production or use of a product comprises a substitute for a certain renewable energy form, if the production/use either results in an increase in the said renewable energy production or replaces this with a renewable energy production with at least the same utility value.

This substitution principle opens up the prospects of the best possible use of the renewable energy resources, including rape seed oil for transport as substitute for covering the agricultural industry's own fuel consumption.

An extensive use of rape seed oil as engine fuel can be implemented quickly and at relatively low costs within the transport sector with its rather standardised engine technology, whereas the very heterogenous agricultural machinery requires a longer transition period. It would be obvious to couple this to the introduction of electricity and hydrogen for road transport on a longer term.

Thus, with a Danish production of rape seed oil for transport purposes, agriculture can contribute to a more environmentally sound transport sector. Precisely this sector has shown a lack of positive environmental results and an increasing contribution to energy consumption and greenhouse effect. A breakthrough for rape seed oil can push the development.

Another and very important effect of the substitution principle is that any increase in the rape seed oil production, including food oil, will increase the potential for rape seed oil and other plant oils as engine fuel.

This is caused by the fact that the market for food oil is saturated, so a new production, e.g. of organic rape seed oil, will replace the same amount of food oil which then becomes available for energy purposes. The effect is increased by the slight difference between non-food and food rape seed oil mentioned below.

2. THE MARKET FOR RAPE SEED OIL FOR ENERGY PURPOSES:

In Germany, where the technology of modification of diesel engines has been developed, rape seed oil is exempted from diesel tax. Consequently, there is a growing market for car conversion. In a period without agricultural diesel tax compensation, there have been signs of a proper tractor conversion market, but the development has come to an end.

In Denmark, rape seed oil for transport is subject to the same taxes as diesel. Therefore it is only the rising oil prices which have created a real interest in running cars on rape seed oil. A possible tax reduction can really push the development.

Since the agricultural industry only pays half CO₂ tax and thus cannot benefit from a tax reduction, it must be expected that at least the initial development will take place within the transport sector where it is also easier and cheaper to introduce the rape seed oil as mentioned above.

For the time being, the Danish consumption of plant oils for transport has by and large been covered by import of non-food rape seed oil from Germany, but lately Danish suppliers have emerged.

In the future, a growing market for rape seed oil for energy purposes must be expected, also owing to a rapidly increasing demand for rape seed oil for heating as substitute for fossil heating oil. With this competing use, rape seed oil is exempted from oil tax. The result is actually a support to the most inferior use of the rape seed oil, whereas the use for CHP and even more for transport is still impeded by taxes.

A tax reduction for rape seed oil for transport will strengthen the market and at the same time bring the development in accordance with the abovementioned principle that an optimum sustainable energy use implies the best possible use of the utility values of the individual energy forms with engine fuel in a class of its own.

With an increasing demand for rape seed oil for energy and a limited price difference (ca. 0,20 DKK/l in September 2000) there is in effect an open market which comprises both non-food rape and rape as a reform crop (crop with EU support). The latter part already contributes to the production of rape seed oil for energy purposes.

This means that all rape cultivation in Denmark, both as reform crop and as non-food, forms part of the market basis for rape seed oil for energy purposes.

With a continuation of the present development it must be expected that an increasing amount of the rape seed oil based on reform crops will be used for energy.

Similarly, it must be expected that there will be a market for an increasing organic production of rape seed oil, especially if the price of fodder cakes can secure the competitiveness of the organic oil. According to the substitution principle described above, an increase in the organic rape seed production will increase the total potential for supply of rape seed oil for transport and other energy purposes, even if the organic rape seed oil is exclusively used as food oil.

3. REFERENCES AND KEY FIGURES:

REFERENCES:

[1] Landøkonomisk Oversigt 1999, Udgivet af De Danske Landboforeninger. (Agricultural-economic summary 1999, issued by the Danish Farmer's Union). Ca.150 pages report in Danish, available at www.ddl.dk

[2] Energistyrelsens statistik (Danish Energy Agency statistics), www.ens.dk/statistik/98/

[3] Jacob Bugge: Anvendelighed af rapporten EMBIO som grundlag for vurdering af biodiesel og koldpresset rapsolie, Nordvestjysk Folkecenter for Vedvarende Energi 2000. (APPLICABILITY OF THE REPORT EMBIO ... (etc), Folkecenter 2000): 30 pages report in Danish. English summary available at www.folkecenter.dk.

[4] EMBIO - Energistyrelsens Model til økonmomisk og miljømæssig vurdering af BIObrændstoffer, Januar 1997, Udarbejdet af COWI. (EMBIO The Danish Energy Agency's Model for economic and environmental assessment of BIOfuels, January 1997, elaborated by COWI): 233 pages two volumes report in Danish.

[5] Note: Rape seed oil for transport 1: Energy and CO₂ balance, Folkecenter for Renewable Energy, 2001. Available at www.folkecenter.dk.

[6] Fodermiddeltabel, Sammensætning og foderværdi af fodermidler til kvæg, Rapport nr. 91. Landsudvalget for Kvæg, Oktober 2000. (Feedstuffs table, composition and fodder value of feedstuffs for cattle, Report no. 91, National Board for Cattle, October 2000): 52 pages report in Danish.

[7] Landbrugsstatistik 1900 - 1965, Bind I, Statistiske Undersøgelser Nr. 22, Danmarks Statistik 1968. (Agricultural Statistics 1900 - 1965, Vol I, Statistical Investigations, Statistics Denmark 1968): 469 pages two volume report in Danish.

[8] Oplysninger om arbejdshestes foderforbrug fra Landbrugets Rådgivningscenter ved Erik Clausen. (Information on fodder consumption by draught horses from the Danish Agricultural Advisory Centre by Mr.Erik Clausen).

[9] Nøgletal for transport 1999, Danmarks Statistik. (Key figures for transport 1999, Statistics Denmark): In Danish, available at www.dst.dk

KEY FIGURES:

Fodder value and energy content in rape cakes from cold pressing of rape seed oil [6]:

Composition of horse fodder and relative area use for this in 1938 [7], [8]:

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