A collaboration between the UK’s leading automotive engineering facilities has resulted in the development of the first plug-in retro-fit hybrid conversion of a combustion engine vehicle. Known as the Affordable Add-on Zero Emissions Vehicle (ADDZEV), the technology that has been developed demonstrates how it may be possible to convert much of the UK vehicle fleet into hybrid vehicles.
Developed to reduce the carbon emissions of inner-city driving, the ADDZEV system was perfected utilising a standard Vauxhall Combo van. Designed to operate as a ‘Plug-In Hybrid Electric Vehicle’ (PHEV), the development team retained the existing conventional front-wheel-drive system of the Combo but added an electric drive, powered via Exide’s low cost advanced lead acid batteries, to the rear wheels. This transformed the van into a hybrid vehicle, capable of achieving an all electric range of over 20 km, from one charge.
Conceived by a consortium of experts from Cranfield University, Millbrook Proving Ground, Provector and Oxford University with battery advice from the European Advanced Lead Acid Battery Consortium (EALABC), the project team behind the ADDZEV believes that, due to simulation studies using real-world data from a range of vehicles, the technology could be scaled up for larger vans and even city buses.
The retro-fit system announced before many manufactured plug-in hybrids have even hit the market could mean that conventional cars could be upgraded to feature the most cutting edge technology.
The system is powered through twin liquid-cooled motors, with a maximum power of 100 kW for maximum gradeability, mounted in a discrete sub-frame under the rear floor of the vehicle, Electric only drive has been limited to propel the vehicle at a speeds up to 60 km/h. For out-of-town driving or higher speed operation, the existing front-wheel-drive diesel power unit provides conventional operation. It can also be configured to switch manually between modes, enabling selection of ultra low emission operation in a low emission zone or city centre.
The batteries are charged through specially-devised control software and power management systems created by Cranfield University and Provector. As a result, drivers have two options for charge – either by connecting to the electricity grid or via the internal combustion engine that generates and stores energy when the vehicle is in motion. This results in a typical operating cost for fuel in a small delivery business that could be reduced by 40 per cent compared to operation on traditional fossil fuels alone. The technology, which can be retro-fitted onto a wide range of vehicles, has performed well in final testing at Millbrook.
Andy Eastlake, head of laboratories at Millbrook, praised the team, concluding: “This has been a diverse project with many challenges but by bringing together the technology providers, system integrators and the development organisation to connect the supply chain directly to the vehicle operator, we have been able to focus not only on what can be delivered but, importantly, on what the end customer wants to operate.”
Conducted as part of the Low Carbon Research and Development programme run by the Energy Savings Trust (EST), the project was jointly-funded by the Department for Transport and the European Advanced Lead Acid Battery Consortium.
Andrew Adonis, Minister for Transport, said: “We want Britain to be at the forefront of ultra-low carbon automotive technology. This research shows we can do that not only by producing new, more environmentally friendly electric cars, but by modifying existing vehicles.
“The technology could even be applied to buses, which will help us to cut our carbon emissions by even more. This, coupled with the incentives announced last week to make electric cars a real option for motorists, will help us to meet our aim for low-carbon vehicles to be an everyday feature of life on Britain’s roads in less than five years.”
Nigel Underdown, Head of Transport Advice at the Energy Saving Trust, said “With CO2 emissions caused by production, driving and disposal, swapping your old vehicle for a new electric or hybrid is not always the most sustainable solution. To be able to retrofit, so that the vehicle becomes more efficient and emits less carbon is a wonderful solution. We commend any steps made to reduce the emissions of the 30 million cars and vans on Britain’s roads today.”
“The project has shown the untapped environmental potential of modifying existing urban vehicle designs to hybrid,” said Nick Vaughan, Head of the Department of Automotive Engineering at Cranfield. “In the current economic climate, relying on the gradual penetration of newly-built vehicles to reduce carbon emissions will not deliver much-needed carbon savings in the short term. Our target for ADDZEV was to demonstrate what could be achieved with the existing urban fleet.”
