Procrustes,
In the UK about 40% of our road vehicles run on diesel, mainly the commercial vehicles, and about 40% of the cars. Everything else is gasoline, apart for a few LPG and electric and steam cars!
The figures that you found rather assumed that everything ran on biodiesel, which clearly can never be the case.
The truth is that we do have spare arable land here, which could be turned over to growing oil seed rape. The oil produced could be used to make locally produced biodiesel, in the same way that some German Farming co-operatives are now doing.
IMHO, growing oil crops is never going to replace all the petroleum fuel needed for road transport and farming, but it could possibly be used to offset possibly 10 or 20%.
For this to become viable, petroleum oil will have to remain at around $60 per barrel, to help stimulate these alternative renewable fuel markets. So long as we have cheap petroleum, these markets and alternatives will struggle to develop, unless they are given a Government incentive - such as has occurred in Germany.
If, I were to run my vehicles and my household requirements solely on rapeseed oil, I would be looking at about 5000 litres per year, which I think is about 30 acres of rape, which is clearly not practical for every household.
Consequently every household will continue to use a mix of fuels and electricity generated from a mix of fuels. If one particular fuel becomes cheaper, as a result of other fuels rising in price, then the energy industry will move in and utilise it. They always use the cheapest fuel. Once that was coal, then it was gas, and now it may be coal again.
The UK energy policy has got way-laid by environmentalists and anti-nuclear institutions. Britain only produces 2% of the worlds CO2. Even if we cut that by 50%, it would be a drop in the ocean compare to the ever increasing outputs from China, India and the USA.
Experts, and well respected government scientists are now saying that we must start building new nuclear plants immediately, there is no other option, otherwise we will face severe power outages by 2010, 2012.
Whilst I personnaly am not a nuclear proponent, I tend to agree, that the time for deliberating is over and we must act now. Typically a nuclear power plant takes 8 to 10 years to build before it starts generating. 9 of our 13 remaining 1st generation plants will be decommissioned by 2010. There will be a shortfall of about 20% of the electricity requirement by 2010.
This is why I am investing in 75 year old Lister technology, and finding my own personal alternatives.
Ken