The road to pure plant oil in diesel engines?

Background, objective and working method

Background

The use of pure plant oils (PPO) is nothing new. Rudolf Diesel tested his first engines with plant oil and declared that: ‘The engine can be fed with vegetable oils’.
However, even today this remains a subject of policy discussions – just as biomass transition– and therefore studies continue to be implemented concerning the use of PPO as a transport fuel, or as a fuel in stationary engines, in order to provide further information. In everyday practice more and more interest is being shown in using this fuel, as shown by the initiatives of various local authorities, provinces and private individuals. This increased interest creates the need for even more information by those initiating such projects, the government and other stakeholders. The policies that are currently being prepared under the framework of implementing the EU’s biofuel guideline also demand more knowledge of this option.
This is why SenterNovem has commissioned the CE consultancy to carry out a study into the environmental aspects, costs and technological aspects of using pure plant oil.
This commission was supervised and funded by the GAVE programme (gaseous and liquid climate-neutral energy carriers), which SenterNovem implements for the Dutch Ministries of VROM (Housing, Spatial Planning and the Environment), EZ (Economic Affairs) and V&W (Transport, Public Works and Water Management).

1.2 Objective and scope

The main objective of this report is to provide a detailed overview of the environmental aspects, costs and technical opportunities of using pure plant oil (PPO) in the Netherlands, plus activities outside the Netherlands, so that stakeholders are better able to relate PPO to other biofuels.
Since PPO can be produced using a variety of raw materials, this analysis is limited to rapeseed oil (made from rapeseed grown in the Netherlands), partly because this is the most-used raw material for the various Dutch initiatives. Also in other European Member States, rapeseed is by far the most important ingredient for PPO and biodiesel. See also [Broek, 2003]. Other possibilities include, for example, producing oil/vehicle fuel from frying fat or animal fats. But the amount of fatty residues is too small to make a significant contribution to the implementation of the EU’s biofuel guideline.
The objective is to sketch the farming of rapeseed and PPO production in the Netherlands during the period 2005-2010, for a situation in which rapeseed is an accepted agricultural crop, and PPO is commercially promoted as an acceptable alternative to diesel. The Netherlands has very little experience in cultivating rapeseed and producing PPO. This is why information has primarily been taken from rapeseed cultivation in Germany and PPO production from rapeseed as currently occurring in Germany. The information generated is therefore not specific to the Dutch situation, but provides a sketch of rapeseed cultivation and PPO production for all of northwest Europe.

Use of sources

In order to create the desired overview concerning PPO, the research team made full use of trade literature, reports on the practical side of PPO production and its use as a vehicle fuel, plus the verbal advice given by experts in the field.
With respect to cultivating rapeseed, the research team used the most recent standard publications available in the Netherlands, farming recommendations and other publications by PPO Lelystad2 and LEI DLO3 . Additional information was received by telephone from Gerard Borm and Marco de Wolf of PPO Lelystad, and Marieke Meeusen of LEI DLO, concerning the publications used. Cultivation in other countries was also given some consideration; see [Parkhomenko, 2004].
Farmers need to use fertiliser in order to grow anything. Unfortunately, this also has an environmental impact, in the form of greenhouse gas emissions as well as acidic and fertilised substances. In order to gain the required insight into these matters and their link to rapeseed farming, researchers used study reports and descriptions of the calculation methods used in government policies. The Louis Bolk Institute provided this expertise via a number of model calculations, and Filip Ehlerd (Alterra) and Maya Boer (CLM) provided additional verbal information.
Information concerning the production of rapeseed oil has primarily been taken from the literature, i.e. reports and articles written by authors such as Remmeler and Widmann, or reports from the Folkecenter in Denmark; all of which are strong supporters of using PPO as a vehicle fuel. In addition, the authors also consulted various reports and reference works from other comparable research institutes, e.g. the University of Sheffield, IFEU (institute for energy and environmental research, Heidelburg) and the Forschungsstelle für Energiewirtschaft. Information from manufacturers of large-scale production equipment was also used, particularly from Lurgi Life Science and De Smet.
For insight into using PPO as a transport fuel, the research team also had considerable contact with practical experts, such as Harold Pauwels and Mr Costenoble (of NNI, the Dutch standards institute) and Nr Noack (of Elsbett). Their information provided a valuable addition to the limited publications on practical experience of using PPO as a transport fuel.
Of these, the publications produced under the framework of the ‘100 Tractors Programme’ in Germany were particularly useful4 .
In consultation with SenterNovem, a peer review of the draft report was carried out by Ecofys and CLM, to evaluate the depth of the analysis, accuracy of the sources and the correctness of the assumptions, starting points and methodology used. As a result of this review, several changes were made to the calculations and starting points. The peer review aimed to better guarantee the reliability of the results to the general public.

Report format

This report consists of the following sections. First a global description is given of the PPO chain (Chapter 2). Chapters 3-7 describe the various parts of this chain and provide answers to questions such as:

Which technical advantages and disadvantages are related to the production and application of PPO as a vehicle fuel?

Which environmental aspects play a role?

What is the ratio between costs and benefits?

Chapter 8 discusses a number of alternatives.
Chapter 9 sets the scores for the technical, environmental and economic aspects against those of diesel and biodiesel, thus allowing the various options to be compared. Attention is also paid to the potential for using PPO in the Netherlands, and any relevant prospects for improvement throughout the chain.
Finally, Appendix A includes a brief inventory of relevant initiatives, activities and developments, both within the Netherlands and abroad. Appendices B-F provide more detailed information on the calculations used etc.

Terms
Since there are various terms used in relation to plant oil, a brief description of these terms is given here. Biofuel - Liquid or gaseous transport fuel that is derived from biomass (EU definition). Bio-oil - Popular term for biofuel (or bio-fuel). Plant oil (also known as: Pure Plant Oil) – Pressing, extraction or similar procedures produce oil from oilretaining plants. This can be natural or refined, but not chemically changed, and meets the engine types and emission regulations (EU definition of ‘pure plant oil’).
Biodiesel – For use as a biofuel, as methyl ester from plant or animal oils, of diesel quality (EU definition).

Due to the uncertainties, primarily the farming-related environmental tax, this analysis uses the ‘ranges’ that can be achieved. In order to provide an overview of the boundaries within which matters such as environment taxes and costs can vary, a worst-case scenario and a best-case scenario have been defined (see Chapter 3).
The changes carried out as a result of the peer review are described in Appendix E.

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