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Toyota Prius Plug-in Hybrid Electric Vehicle trial results


Interim findings from Toyota and EDF Energy ’s demonstration of the Prius Plug-in Hybrid Electric Vehicle (PHEV) in London confirms that the technology can deliver greatly improved fuel efficiency and lower emissions in urban driving.

The petrol-electric Prius PHEV can be plugged in to an electricity supply to extend its electric-only range to 12.5 miles, and this also improves its fuel economy and lowers its tailpipe emissions.

Early indications show that the average fuel consumption in the London area is 27 per cent better than an equivalent diesel car, although Toyota has not released the actual fuel consumption results.

Data analysed from the full European programme shows average fuel consumption that is 36 per cent better than a best-in-class diesel car of equivalent size, and 49 per cent better than a similar size best-in-class petrol model.

Working in partnership with EDF Energy, the UK’s largest producer of low carbon electricity, Toyota has leased 20 PHEVs to London-based businesses and organisations to monitor both vehicle performance and recharging patterns.

Based on the third-generation Prius, the PHEV is equipped with a lithium-ion battery that lets the car be driven for longer distances and at higher speeds on electric power alone. Battery charge can be topped up simply by plugging the car into a dedicated electricity supply at the driver’s workplace, on-street charging point or home.

Details of journey times, speeds and distances, fuel usage and vehicle recharging have been logged since the three-year demonstration began last summer. Information gathered so far in the UK shows that:

? Average journey distance has been 7.3 miles, with 59 per cent of all journeys covering between 3.1 and 12.4 miles

? Average speed has been 17.7mph, with 69 per cent of journeys at speeds less than 18.6mph

? Initial fuel consumption data indicate performance is 27 per cent better than an equivalent diesel

? Average recharging time is 72 minutes

? Where drivers have access to a domestic charge point, more frequent recharging occurs

These results show that PHEV’s performance is well-suited to the demands of urban driving: the car is capable of running for up to 12.5 miles solely on its electric motor in EV mode – battery charge and road conditions permitting – at speeds up to 62mph. This means it can accomplish the great majority of typical urban journeys with zero petrol consumption and tailpipe emissions.

Furthermore, should the battery charge be used up in the course of a journey, or before a recharging opportunity, PHEV will seamlessly switch to power from its full hybrid system, which includes a 1.8-litre VVT-i petrol engine. This means the driver need suffer no “range anxiety” about the distance the car can cover.

User perceptions of the PHEV are also being monitored through regular interviews with drivers conducted and analysed by Oxford Brooks University. Feedback received so far shows a very positive response to the car and its performance, and to the procedure and equipment used for charging.

The experience already gained from the London demonstration supports the positive results Toyota is witnessing with its PHEV demonstration programmes with 200 cars in 18 countries across Europe, including a large-scale project with EDF involving 100 PHEVs in the French city of Strasbourg.

Data analysed from the full European programme shows average fuel consumption that is 36 per cent better than a best-in-class diesel car of equivalent size, and 49 per cent better than a similar size best-in-class petrol model.

The results show that the PHEV’s 12.5-mile (20km) EV range is sufficient to cover most day-to-day travel needs of the drivers taking part in the programme – the average European journey distance is 8.2 miles (13.2km), and two thirds of all journeys are of less than 12.5 miles.

Twenty-two per cent of drivers have even been able to drive further than the official 12.5-mile range in EV mode.

Electric-powered driving so far has accounted for one third of all miles driven in the PHEV demonstration.

A significant part of the programme has been EDF Energy’s installation of smart-metered charging infrastructure at workplaces and a home location. Consumption data tied to driver, vehicle and charge point are captured through a keypad identification system to gain an in-depth insight into charging patterns and preferences and use of the charging infrastructure.

Initial results reveal different approaches to recharging across the vehicle operators taking part in the programme, with dedicated drivers recharging most frequently and therefore maximising the low carbon and cost mileage benefits.

The results of the trial have informed the development of EDF Energy’s latest recharging product, EcoRecharge. This features an intelligent timer to enable easy off-peak recharging, and a smart meter to provide customers with statements on their vehicle’s carbon and electricity consumption. EDF Energy’s low carbon charge point package means households with a plug-in vehicle can save money by receiving 20 per cent cheaper electricity during evenings and weekends with its Eco 20:20 tariff.

The London leasing demonstration is part of the Technology Strategy Board’s Ultra Low Carbon Vehicle Demonstrator Programme and benefits from funding support from the UK Government through the Office for Low Emission Vehicles (OLEV).

Speaking on behalf of Transport for London, one of the organisations taking part in the demonstration programme, Mike Weston, Director of Operations said: “We are working hard to reduce the environmental impact of our support fleet and are currently using of a range of electric and plug-in hybrid vehicles including the Prius Plug-in Hybrid. These vehicles help to reduce CO 2 emissions and improve London’s air quality. With the launch of the Source London network of electric vehicle charge points I’m certain that even more drivers will also choose electric or plug-in hybrid vehicles.”

The on-going data collection continues to provide Toyota and EDF Energy with a great resource for learning more about the priorities and preferences of end users, both in terms of how they use their vehicle and their recharging requirements. Together with experience and information gained from other demonstrations in Europe, this will enable an effective strategy to be prepared for designing and marketing a full production PHEV and for shaping and introducing the most effective charging opportunities and infrastructure to promote low carbon energy usage.

The organisations taking part in the programme are Transport for London, the Government Car and Despatch Agency, the Metropolitan Police Service, News International and Sky.

EDF Energy is one of the UK’s largest energy companies and the largest producer of low-carbon electricity, producing around one-sixth of the nation’s electricity from its nuclear power stations, wind farms, coal and gas power stations and combined heat and power plants. The company supplies gas and electricity to more than 5.5 million business and residential customer accounts and is the biggest supplier of electricity by volume in Great Britain.

The London PHEV leasing demonstration is one of eight projects in the Technology Strategy Board’s national Ultra Low Carbon Vehicle Demonstrator programme, part-funded through the Office for Low Emission Vehicles (OLEV) and administered by Cenex.

The Technology Strategy Board is a business-led executive non-departmental public body, established by the Government. Its role is to promote and support research into, and development and exploitation of, technology and innovation for the benefit of UK business, in order to increase economic growth and improve quality of life. It is sponsored by the Department for Business, Innovation and Skills (BIS). For more information please visit .

Although it has a 12.5 mile electric-only range, the Toyota Prius Plug-in is still primarily a petrol-engined car; whereas the Vauxhall Ampera Extended-Range Electric Vehicle (E-REV) is almost the opposite – it’s always an electric car, with a petrol generator able to provide extra range.