A link to a Swedish manufacturer of small and medium scale processing equipment for estrification of oils:

http://www.ageratec.se/biodiesel_index.asp?lang=EN

Thank's for this link. My brother in law is investigating for potential market applications in France exactly for this material. He claims 1 ha of rapeseed oil needs 50 liters of diesel to be completly worked from seeding to harvest and yields 2000 l of rapeseed oil. Waste of the process can be used for various applications like cow feeding.

I still have concerns for global EROEI, since most studies don't include all energy requirements like construction and maintenance of all the engines (ever seen how a wheel on a tractor is changed ?), irrigation (in our countryside water has to be pumped for irrigation. Water volume required has been increasing in the past years). Volumes of fertilizer and pesticides vary enormously from one published study to the other as do the estimated BTU's for the manufacturing of these products (see links provided by robert rapier for an estimation of these spreads).

And for the long term I keep asking my brother in law to please consider soil depletion (a very real issue, since plants do need other elements than N,P,K and CO2 to grow), surface of arable land (in slight excess in France but already competing with agriculture for food). Also don't forget that EROEI of our whole transportation system is <<1. This means that energy taken from biomass is taken out and isn't put back into the system except for CO2. For now there is an excess biomass with regard to the whole ecosystem, otherwise oil wouldn't have formed. So we can sacrifice some of this ... but at what ecological cost and in what places ? Moreover, if we increase the area of arable land, will we really increase the total biomass (i.e. the carbon sink) ? I stay with stuart staniford on this point, increasing our total C02 emission is probably very deleterious.

I must say that these arguments don't hold for someone involved in agriculture. In Europe biodiesel will increase, regardless of what we say or may think, unless the consequences become disastrous or the economy breaks down.

The soil depletion issue is on my mind as well, and for the same reason. Using biomass for fuels removes more than nutrients from the system. The basic soil structure is at risk from the removal of carbon, which ends up in the atmosphere, where the feedback from warming contributes further to the loss of carbon from soils, as I posted here.
From what I've read, biomass left on the surface decays quickly and contributes relatively little to soil tilth.  Matter left inches to feet below the surface and undisturbed by tilling tends to remain.  That matter consists of plant roots, not stalks and stems.

This points toward using zero-till, leaving an optimum amount of organic matter on the surface and returning all nutrients either as liquid effluent or ash.  If some of the carbon can be returned as charcoal (inorganic) and tilled in every ten years or so, the nutrient-holding capacity of the soil could be substantially increased at the same time as carbon is sequestered for millennia.

EP,

You are absolutely right!
(I don't often find myself agrreeing with you so wholeheartedly ;-)
No-till, leave as much as possible in place or return everything you don't use.
These principles are the essence of the Masanobu Fukuoka philosophy of natural farming. I believe such principles can be applied in varying situations with positive long-term results.
i.e. lower external inputs (energy, materials) and healthy soil.
Mr. Fukuoka has been analysing energy inputs versus energy outputs of farming since the 1930s.
Blinded by the "Green Revolution", most people dismissed his valid concerns about the disaster being created by "modern" farming methods.