“Frequent starts and stops, long periods of idling, very short distances, often in first and second gear only – even Volkswagen’s most economical TDI motors aren’t as efficient as they could be under these driving conditions. Electric motors are different – there’s no leaving the engine running, no idling, no clutch, no changing gears. Another advantage is that energy is recovered when braking”, says Strunz, not without a hint of pride in his voice.
The Caddys clocked up a good 14,000 kilometers in 80 days, travelling up to 44 kilometers without having to be recharged. The electric vehicles’ lithium-ion batteries need around 90 minutes to “refuel”, so that two rounds a day are possible. The 85 kW (115 PS) electric motor, taken from the future Golf blue-e-motion, has an electronically limited top speed of 120 km/h. Its nifty acceleration from standstill drew unanimous praise from the drivers. Deutsche Post DHL was in turn pleased at the low operating costs – the electricity cost around six cents per kilometer, not even a quarter of the price of diesel fuel. It also discovered that electric vehicles cost less to maintain than vehicles with a combustion engine.
Feedback from the postal delivery workers on the Caddy blue-e-motion provides the Volkswagen Group’s developers with important insights for technical improvements and the construction of future series. “When it’s raining and our clothes are damp, the windows fog up while we’re sitting in the car. The heating has to unfog them quickly”, says Ivonne, touching on a safety issue – unobstructed visibility, even in damp conditions or below-zero temperatures. “Safety is our number one priority in electric vehicles as well”, stresses Jörg Strunz. The problem is that the electric drive produces very little warmth, meaning that, for the time being, the battery is the only source of energy for the heater. This reduces the vehicle’s range.
Engineers still have to solve tricky problems like these on the road to an electric future. Batteries need to be made more powerful, safer and cheaper, a charging infrastructure has to be developed and the energy required to “refuel” must be generated from renewable sources. Volkswagen’s electric age is starting soon: the zero-emission up! and Golf blue-e-motion are scheduled to quietly take over the streets from 2013, followed by the Caddy blue-e-motion. If it were up to the drivers from DHL, they would sooner switch over to electricity today than tomorrow.