The car is started using unleaded petrol but automatically switches to methane when the engine is "up to temperature". If the methane tank runs out the Bio-Bug reverts back to petrol.
GENeco is part of the Wessex Water group of companies and operates one of the largest sewage treatment works in the country to recycle waste, produce renewable energy and provide the agricultural industry with a nutrient-rich fertiliser.
With support from the South West Regional Development Agency, GENeco fitted equipment to treat gas generated at Bristol sewage treatment works so it could power the VW Beetle in a way that doesn’t affect its performance.
Mohammed Saddiq, GENeco’s general manager, said: “Our site at Avonmouth has been producing biogas for many years which we use to generate electricity to power the site and export to the National Grid.
“With the surplus gas we had available we wanted to put it to good use in a sustainable and efficient way. We decided to power a vehicle on the gas offering a sustainable alternative to using fossil fuels which we so heavily rely on in the UK.
If you were to drive the car you wouldn’t know it was powered by biogas as it performs just like any conventional car. It is probably the most sustainable car around.
GENeco claims 70 homes flushing for a year can power one Bio-Bug for 10,000 miles - the average annual mileage for a UK motorist. So that would power 285,714 cars, less than 1% of the 32m on the road.
Like other alternative motor fuels from compressed natural gas to dimethyl ether to even hydrogen, bio-methane could gain acceptance as a fuel for auto fleets or buses, which need a centralized location for refueling.
Mohammed Saddiq added: "Previously the gas hasn't been clean enough to fuel motor vehicles without it affecting performance"
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