Tuesday, 19 November 2013


Logo and text now affixed to buses used in the venture (Malcolm Conway)

On the 7th of November Boris Johnson announced plans to run London’s buses on biofuel from food waste — including chip fat and a suet-like substance.

The Mayor’s environment adviser Matthew Pencharz suggested the pilot scheme could be rolled out across Transport for London’s bus fleet.
But the proposal to operate 120 buses across 10 routes on a biofuel and diesel blend was immediately dismissed as a gimmick. Critics said that while biofuel could cut CO2 emissions they would not reduce the levels of deadly particulates that have helped make London’s air quality among the worst in Europe.
They also questioned the point of the pilot when TfL was already testing four electric buses that could leap-frog any other technology if successful.
Stephen Knight, Lib-Dem environment spokesman for London, said: “Putting a part blend of biodiesel in 120 London buses is just a gimmick as all forms of diesel create air pollution.
“When over 4,000 Londoners face an early grave each year due to London’s appalling air pollution the Mayor’s first priority should be ensuring that London buses run entirely on electricity.”
However, Mr Pencharz insisted the scheme was a cost-effective way of reducing CO2 emissions by about 15 per cent for each bus with no mechanical changes required.
Mike Weston, TfL’s director of buses, said: “Using biodiesel recycles waste products reduces carbon emissions and we hope that by successfully trialling it we will encourage other transport operators to consider using it too.”

The full allocation of 120 buses at Stagecoach London's Barking Garage will be used for this venture, of which 100 are required for the peak vehicle requirement on ten TfL bus routes (5,15,62,101,145,169,366,387,687).

There are four different types of bus operated on the routes, ADL E400 and E40D Enviro400 and Dennis Trident double-decks, and ADL  Enviro200 and Optare Versa single-decks. Examples of each type are illustrated below on the respective routes throughout East London, the images courtesy of Haydn Davies.

The Other Point of View

Focus Transport asked Cumbria Classic Coaches for their point of view as they had, until recently, run their fleet on bio-diesel from a local supplier who processed and re-cycled vegetable cooking oil.

Will Hamer from Cumbria Classic Coaches said they wanted to do their bit to reduce emissions and initially thought that there also could be a cost saving.
Although there were positive issues such as increased power and torque and quieter running they were massively overshadowed by a number of negatives that couldn't be ignored.
The fuel caused glazing within the injector pumps and rack, like you would get on the inside of a chip pan resulting in major problems with inaccurate fuel injection.
The bio-diesel was so acidic that it destroyed seals within the lift pump. It leaked into the sump of the injection pump and also into the main engine sump thus diluting the engine oil.
It cleaned out the main fuel tanks of each vehicle and sent residue into the filters and clogged them mostly at the inconvenient times, even though there was a programme to check and change filters at more frequent intervals.
During cold weather the fuel waxed and made engine starting more difficult. Fuel economy suffered by 2mpg and when what were advantageous fuel duty rates increased during the time the company were using bio-diesel all chances of cost saving were wiped out.
It was not unknown for a purple gel to form in the bottom of the fuel storage tank at the depot. This would have caused major problems to the engines and it had to be separated and was credited for by the fuel supplier who replaced the shortfall.
On reflection Will said that it had been a useful experiment and had assisted in improving emissions. MOT's were easily passed due to the absence of harmful particles in the exhaust emissions but they could not continue due to the number of overwhelming negatives associated with using the fuel.
The fleet of AEC, Guy and Leyland buses and coaches were used extensively on a variety of tours, bus routes, film & TV contracts and Private Hire especially Wedding hire during this period, and provide quite a contrast to the more modern vehicles used in the current venture.

Will ended the interview by saying that he wished the London scheme well and that he hoped that the problems that Cumbria Classic Coaches had encountered would not be experienced in this latest effort to use this type of fuel. He also added that he hoped that vehicle warranties would not be affected in the more modern vehicles that are operated in London.

Here the company's former Crosville Motor Services Bristol Lodekka is refuelled with straightforward diesel at a local outlet in Kirkby Stephen at the end of a busy day, the driver no doubt expressing his delight at being at the helm of such an interesting vehicle (or not as the case may be!)


With the aforementioned problems came a considerable amount of head scratching and consultation to remedy the situation. You can maybe add your own interpretation and comments to the following two images

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