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PHEVs are now the most Reliable – Electric Vehicle Routing Option 5

Date:07-29 08:21 Source:Internet Info Agency Authour:Li Anding

Volkswagen Group China CEO Jochem Heizmann once asked me about the viability of promoting Volkswagen’s plug-in hybrid technology in China. In my opinion, plug-in hybrid electric vehicles (PHEVs) are now the most reliable, energy efficient, and eco-friendly new energy vehicles in China, offering a better option than all-electric vehicles (Evs), which have to balance battery weight and driving range. At Auto China 2014, we saw a number of concept PHEVs launched by China’s domestic brands. In the past two years, Volkswagen has also launched a range of PHEV models, and together with a number of industrial, academic and research institutions, has participated in a 4-year PHEV research project led by the German government. Now it has become the third major automaker, following Toyota and GM, to shift its priority in new energy vehicle development from EVs to PHEVs.

The plug-in hybrid origiinates from two sources. One is Toyota, where it was developed to back up hybrid vehicles with electric vehicle technology for further fuel economy, once hybrid vehicles’ fuel-saving potential began to approach its limit; this they called the “plug-in hybrid electronic vehicle" (PHEV). The other source is GM, where technology has been developed to generate electricity from fuel and recharge the battery once the electrical power is exhausted. This overcame the EV limitation of driving range, and thus it was named the “extended-range electric vehicle" (E-REV). Because Toyota was an early adopter of R&D in this technology, PHEVs are used more widely in China, covering both types of electric vehicles.

The “Plug-in” is based on the original hybrid technology. With a smaller Li-ion battery pack for charging and energy recovery, a PHEV can cover 20km on a single charge, and switch back to the hybrid engine when battery is depleted. When the Prius was introduced in China, the government authorities considered the 20km driving range too short and thus disqualified the model for new energy vehicle (NEV) purchase incentives. However, Toyota’s technical staff told me that 20km is the right value calculated on the basis of a large volume of statistical data, balancing average travel needs against battery cost and fuel economy. 20km on a charge enables smaller battery packs, therefore lower costs. Yet this 20km of pure electric capacity can improve a hybrid vehicle's comprehensive fuel efficiency from 50% to 74%. The GM E-REV Volt is designed to travel 80km on a charge. With a fuel engine and an electric motor coaxially connected in series, the vehicle can reach a driving range of 570km between fill-ups, since the fuel engine can start to generate electricity to recharge the batteries once their charge is exhausted. But compared to the Prius, GM’s Volt has to carry an additional 120-150kg of battery weight, and the international average cost for this type of Li-ion battery is US$809 per kilogram. As a result, the Volt’s price is about 10% higher than the Prius.

In a test drive, I drove a Volt from a hotel near Quanye Bazaar in Tianjin to Xuanwumen in Beijing. With 3 adults on board and the air conditioning on, I was still able to accelerate from time to time on the way without the “range anxiety” associated with all-electric vehicles. Ultimately, the car ran 59.9km under all-electric mode (80km is the theoretical capacity) and 83.6km under extended range mode, consuming 10.4KwH of electricity and 7 liters of fuel.

Volkswagen’s PHEV product can travel 50km on a charge, which makes it just eligible under China’s official standards for purchase subsidies for new energy vehicles.

China’s own BYD brand started long ago on a dual-mode electric model, the D3DM, which is actually an E-REV product. At present, its PHEV QIN is relatively more mature in technology, and the price is close to that of a conventional vehicle once purchase subsidies are included.

Two years ago in Shenzhen, BYD collected statistical data on F3DM users with typical mileage requirements in excess of 60,000km, and the results showed that the ratio of fuel mileage and electric mileage was 1:1. Electric mileage covered most commuting on weekdays (60km between recharges) and fuel mileage was mostly for long journeys at weekends. If the hybrid model's energy recovery is taken into account, this fuel efficiency is impressive.

Indications are that BYD’s PHEV models could soon be granted NEV subsidies in Beijing.

(The author is a senior auto observer, senior reporter of Xinhua News Agency, and President of Internet Info Agency.)


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