London’s iconic black cabs to go green
May 23, 2008 While improvements in engine technology have led to a marked improvement in fuel efficiency and carbon emissions in vehicles running on internal combustion engines in recent years, even greater cuts in emissions need to be made to tackle the global environmental problems associated with them. We’ve seen commercial airlines turning to biofuels, trucks running on liquefied natural gas and buses using ethanol engines. One of the most promising solutions for the humble car of the future could is hydrogen fuel cell systems, with a number of car manufacturers investing heavily in development.
The only local emissions from hydrogen fuel cell systems come in the form of water vapor. With the aim of accelerating the introduction of this environmentally friendly technology to commercial fleets, a collaboration led by hydrogen fuel cell developer, Intelligent Energy, and including Lotus Engineering Ltd, LTI (London Taxis International) Ltd and TRW Conekt, will see a fleet of classic London cabs fitted out with zero emissions hydrogen fuel cell power systems in time for the Olympics in 2012. The program is part of the UK government's Technology Strategy Board recent allocation of funding of £23 million for 16 innovative low carbon vehicle development programs.
The taxis will be powered by fuel cells and batteries configured into an electric hybrid, so the vehicles will be able to operate for a full day without refueling. They will be capable of achieving speeds of up to 75 mph, with the fuel cell powertrain providing better acceleration than standard taxis and the fuel cells system will be able to function at temperatures as low as -20°C, and will fit in the space allotted to the engine in the current LTI TX4 taxi design. One of the big hurdles facing the introduction of hydrogen fuel cell vehicles has been the lack of infrastructure for refueling such vehicles and to overcome this the taxis will top up their hydrogen tanks at central depots with the refueling process taking only a few minutes.
Intelligent Energy are hoping the use of London’s iconic black cabs will provide evidence of the commercial viability of hydrogen fuel cell technology and aim to introduce other commercial fleets of zero emission fuel cell hybrid taxis in other cities by 2014. Their technical teams have already successfully integrated fuel cell power systems into motorbikes, delivery vehicles and even aircraft, recently providing the power system for the world's first manned fuel cell powered flight.
The partners will bring their respective expertise to the project. Intelligent Energy will test and optimize the fuel cell system with the aim of developing a durable and dependable fuel cell engine providing power output of >25kW, that will be capable of providing reliable power to a fleet of 50-100 vehicles for 2012. Lotus Engineering will work to package the components of the fuel cell drive system and to build control systems that optimize the performance of the fuel cells and electrical drive systems as well as testing a range of vehicle operating systems, such as refueling, hot and cold start performance and durability testing on a simulated London taxi duty cycle. TRW Conekt will lead the safety analysis program, including braking and steering systems and will also be involved in other activities such as testing vehicle controls, electrics and electronics, while LTI will provide donor vehicles and assist with structural modifications to the chassis of the taxis.