I happen to work in the biofuel industry, so I hope I'm well-placed to comment on the issues
Bio-fuel doesn't just have to come from crops, there are new experiments to create large volumes of bio-diesel from algae.
Absolutely right. First generation fuels from food crops will never reach more than a few percent, for reasons of crop availability and technical limitations. Algae is one of the most advanced second generation technologies, and "BTL" biomass to liquids is not far behind.
Apparently even if the entire arrable farming land of the UK was turned over to growing bio-fuel it would still not provide anything like enough for our needs, and that's before the problem of growing crops for human and animal consumption, and the loss of farm land for housing. On a world scale the situation is no better, and even coming close to predicted future demands for fuel would mean massive deforestation, which defeats the point from an environmental point of view.
Transport fuel will never be 100% biofuel. However, the use of an increasing percentage, from sustainable and especially waste biomass sources, can provide a large component. Growing corn for ethanol is unsustainable and insufficient; however biofuels from waste (like waste wood, non-food parts of corn and even municipal waste) as well as coal and gas, can be used to make liquid fuels for the overall mix. It is all about that balance.
yeah but bio fuel is not a viable option, we need the land to grow food not fuel. Alot of land does not create alot of fuel to make it worth while. hope XC do not put it inot practise, it's okay for royal train though
Second generation is a different matter - billions of litres can be derived from agricultural and forestry residues and the long term aim of the industry is to move as quickly as possible away from food crops as a feedstock. My source is the International Energy Agency, amongst others.
Incidentally you need around one tonne of biomass to produce a barrel of oil equivalent.
All diesel in the UK has been termed as "bio-diesel" since 2009
A small percentage is sourced from biological sources, rather then synthetic sources
Now that it exceeds 5% it is nothing more than a publicity stunt
The benefits are negligible
That's not correct. It is true that most diesel in the UK contains around 5% fatty acid methyl ester biodiesel and can be termed "B5" but the fuel itself is not termed biodiesel. The term biodiesel refers only to the fatty acid methyl ester component. In fact, Tesco's fuel has been 5%ish for a while (as gasoline around 5% ethanol) for some time without any publicity.
The EU target of 10% biofuel in the European fuel pool by 2020 will have a modest effect on overall emissions (if you believe that CO2 causes climate change) but it is about a journey. 1st gen is a stepping stone, 5% is a stepping stone, 10% in 10 years is a stepping stone, all required on the route to fully sustainable transport.
You use the term "synthetic diesel" which is actually a term for second and third generation biofuel, as well as diesel from coal and gas (i.e. it is diesel but has not come from oil). The South Africans have made synthetic fuel for decades, since the oil embargo, and the US recently approved such synthetic fuel for use in aviation. British Airways are sponsoring a forthcoming plant to make synthetic biofuel from waste in East London.
You are partly right to say the the benefits of 1st gen biofuel can be low in terms of "greenhouse gas reduction potential", some of the savings are modest compared to fossil diesel.
One benefit of a true synthetic BTL diesel is that the carbon saving can be very large (up to 90%) that of fossil diesel, and can be made from marginal and waste crops. So the benefit is most certainly not negligible.
In the case of the royal train (back on topic), if the claim is true, the 67 is running on first generation 100% FAME biodiesel, which will be from food sources such as rapeseed. I have certain doubts about whether the claim is true, at least for anything but the demonstration run mentioned in the press release. The logistical and technical challenges of ensuring a separate fuel supply for two locos, for what is a small fraction of their duties, seems a little easier to say than to do!!
I hope this helps!