Fuel Cell Electric London Taxi Case Study
Intelligent Energy has led a consortium to introduce zero emission fuel cell electric taxis to London. The consortium developed and integrated robust, high efficiency, Proton Exchange Membrane (PEM) fuel cell electric powertrains into TX4 taxis from The London Taxi Company. The zero emissions London taxi is a hydrogen fuel cell and lithium battery powered electric hybrid providing a 250-mile driving range, whilst retaining all the passenger and luggage space of a conventional London taxi.
Designed with taxi drivers in mind, the fuel cell electric London taxi is capable of a full day’s operation (8 hours) and can be rapidly refulled, in less than 5 minutes. The taxi also benefits from zero road tax, an advantage of emitting zero CO2 and zero particulates. With no moving parts in the fuel cell and with electric motors driving the wheels, ride comfort and reliability are improved compared with conventional taxis.
The fuel cell electric London taxis are now featuring in the HyTEC programme and running in a London fleet from July 2012.
Key benefits of fuel cell systems
- Zero tailpipe emissions
- Significantly increased range compared to a battery only alternative
- Rapid refuelling (typically <5 minutes)
- Quiet operation
- Overall improved passenger comfort
- High system efficiency
- Continuous system health monitoring and predictive servicing
- CAN control interface
- Low cost and compact design fuel cell stack with metallic plates
- Reduced stack size incorporating proprietary stack cooling and humidification (no cooling plate)
- Reduced balance of plant components with no requirement for pre-stack humidification
- No “science breakthrough” required to realise planned cost reduction curves
- Transferable power train technology suitable for a variety of automotive and other applications
Fuel cell hybrid taxi specification
| Powertrain | Fuel cell and high voltage battery hybrid coupled to electric motor |
|---|---|
| Power | 100kW |
| Torque | 550Nm |
| Fuel | Compressed hydrogen @ 35MPa (75MPa option available) |
| Top speed | 93mph |
| 0 to 60mph | 15.5 seconds |
| Range | Up to 250 miles (165 miles on NEDC) |
| CO2 emissions | 0 g/km |
Fuel cell system specification:
| Performance | Rated net power configurations | 30kW |
|---|---|---|
| Output voltage | 200 to 400V (unregulated) | |
| Rated current | 150A | |
| Emissions | Water vapor | |
| Fuel | Fuel type | Hydrogen gas |
| Fuel quality | 99.95% (subject to composition) | |
| Supply pressure | 3 to 7 bar gauge | |
| Fuel consumption | <345 SLPM (at maximum rated power) | |
| Fuel storage | External | |
| Environmental | Storage temperature | -25°C to 60°C |
| Operational temperature | -25°C to 37°C | |
| Relative humidity | 0% to 95% | |
| Elevation | 0 to 1000 metres | |
| Physical | Mass | 170 kg |
| Volume | 177 litres |