Thursday, March 13, 2014

Volkswagen: e-mobility and sustainability; Part 1, the e-Golf and Golf GTE

In conjunction with its annual media and investor conference, Volkswagen is staging a two-week (8 - 21 March) e-mobility event at Berlin-Tempelhof. Although the company (both the brand and the larger Volkswagen Group) has been researching electromobility for a number of years; has previously outlined accelerating implementation of electric drive projects; and currently has two battery-electric passenger cars on the market (e-Up! and e-Golf) with other plug-in models following, the event marks a very large and public stake in the ground, in terms of defining the current and future importance of e-mobility for Volkswagen.
At the event, Volkswagen is presenting its new battery electric e-Golf, along with the battery-electric e-up! and a pre-production prototype of the plug-in hybrid electric Golf GTE. Although the other electric-drive vehicles are prominent, the focus is on the new e-Golf—the first electric version of the most successful European car.
Volkswagen is organizing the e-mobility weeks to inform politicians and policy-makers; journalists; dealers; fleet managers (70% of sales in Germany are to fleets); and the general public about present and future e-technologies and e-vehicles, as well as to make the case that, as one presenter put it: “e-mobility is at the heart of Volkswagen”.
Green Car Congress is attending the event as the guest of Volkswagen; the report will fall into multiple parts, with the initial reports first addressing the three specific e-drive plug-in vehicles highlighted at the e-Mobilitätswochen event, with subsequent reports addressing larger issues of sustainability, life cycle analysis, and technology developments.
The e-Golf
The Golf is core to Volkswagen; the company has sold more than 30 million units since the first introduction in 1974. The e-Golf is based on current 7th generation Golf, itself based on the MQB toolkit. As the Modular Transverse Matrix (MQB) architecture that underpins the new Golf A7 is so flexible, Volkswagen was able to integrate the lithium-ion battery in a space-saving frame in the vehicle floor, under the front and rear seats and in the center tunnel. Like the electric motor and the transmission, the battery pack was also developed in-house at Volkswagen and is made at the company’s facility in Braunschweig, Germany.
e-Golf driving impressions
We had the opportunity to take the e-Golf on about a 30 km circuit through Berlin; our preferred driving configuration was in Normal mode with B (maximum) regen.
The smoothness, quiet, handling and performance of the production e-Golf is markedly improved from the prototype e-Golf, based on the earlier A6-generation Golf, we had a chance to drive two years ago. (Earlier post.)
Handling is crisp with no sense of wallowing through corners, and regen is smooth while also being firm (especially in the B setting). Regen is not aggressive enough to provide a full “one-pedal” driving experience, but it’s close, especially in city traffic. Energy consumption for our trip (which included some highway time) was recorded as 14.0 kWh/100L. The cabin is free of even slight audible cues of earlier electric drives (light whining, fan noise, etc.).
In short, Volkswagen met its design target; the e-Golf drives like a Golf that happens to have a battery-electric powertrain, rather than a battery-electric vehicle that is labelled a Golf.
Key atributes of the e-Golf are its design for “everyday practicality, just like every other Golf” and its engineering for large-scale production. By leveraging the MQB platform, Volkswagen is able to manufacture different variants of the Golf—gasoline, diesel, CNG, plug-in hybrid and battery-electric e-Golf—“bumper to bumper on the production line.” This last attribute, Volkswagen believes, will give it a key differentiator and competitive advantage, particularly in terms of being able rapidly to expand electric drive offerings across its lines as market demand determines.
Our toolkits are evolving into a core innovation platform; with them, we can bring model variants, technologies and innovations to series production rapidly and flexibly. And they help us tune our vehicles more precisely to customers’ wishes.
For example, we will offer more and more models with the entire range of state-of-the-art drive technologies, from highly efficient diesel and gasoline engines, through natural gas-powered engines, down to pure-play electric vehicles and plug-in hybrids. We leave it to our customers to chose the model they want to drive.
To start with, we are offering the e-Golf for this year, others will follow suit. Thanks to the toolkits, we are also in a position to respond quickly and flexibly at any time to new market trends or shifts in demand. In our Group, electric cars aren’t built in separate plants, they are made bumper-to-bumper with diesel or gasoline models. I am convinced that the big winner of the innovation cavalcade will be our customers.
In a few years time, you will be able to get almost every [Volkswagen Group] car as a plug-in hybrid. We have said for a long time that we will only enter into the market when we are certain we have fully mastered this technology, not just technically speaking but also market-wise.
—Prof. Dr. Martin Winterkorn, Chairman of the Board of Management, Volkswagen AG, speaking at the annual meeting
Lifecycle analysis. Volkswagen has begun publishing summaries of lifecycle assessments for its vehicles. All information environmental ratings are checked and certified by the independent inspection agency TÜV NORD. The e-Golf’s CO2emissions are reduced by 99% in the use phase compared with the 63 kW/85 hp Golf 1.2 TSI when “BluePower” (green electricity) is used. Over the full lifecycle, the e-Golf shows a 61% decrease in emissions.
BluePower energy comes exclusively from hydro-electric generating plants in Germany, Austria and Switzerland. Cooperation and sales partners are the German company LichtBlick SE and the Volkswagen Bank.
Even if the e-Golf is run on conventional electricity—e.g. with the EU 27 electricity mix— its CO2 emissions are still 26% lower over the full life cycle than those of the Golf VII 1.2 TSI.
Golf-lca
CO2 emissions over the full life-cycle (t CO2e). Click to enlarge.
US launch. Currently on-sale in Germany, the e-Golf will be launched in late 2014 or early 2015 in the US. (All e-Golfs will be built in Germany for the time being.)
The e-Golf will come with an 8-year, 100,000-mile battery warranty (against 70% capacity). A roadside assistance program will offer free towing 100 miles from customer’s home as a means of addressing range anxiety. A carbon offset program will be introduced covering the e-Golf from manufacturing and shipping through warranty period use. Volkswagen is also looking to implement a residential solar power incentive program.
Basics. The e-Golf is powered by an 85 kW EEM-85 synchronous permanent-magnet AC motor which develops 199 lb-ft (270 N·m) of torque. The e-Golf accelerates from 0 - 25 mph (40 km/h) in 4.2 seconds and from 0-60 mph in approximately 10.4 seconds. Top speed is electronically limited to 87 mph (140 km/h). The e-Golf has a range of up to 190 km (118 miles) on a single battery charge (24.2 kWh) based on an average energy consumption of 12.7 kWh per 100 km.
Three driving modes (‘Normal’, ‘Eco’ and ‘Eco+’) and four levels of regenerative braking (‘D1’, ‘D2’, ‘D3’ and ‘B’) help drivers to get the maximum range out of each charge.
264 cells output 24.2 kWh. The e-Golf has a DIN unladen weight of 1,510 kg (3,329 lbs) (vehicle unladen weight with 68 kg driver and 7 kg of luggage, determined per RL 92/21/EEC: 1,585 kg); the lithium-ion battery accounts for 318 kg (701 lbs) of this amount and is located between the front and rear axles. It consists of 264 individual cells, which are integrated in 27 modules (each with six or twelve cells).
The voltages of the cells add up to a nominal voltage of 323 V. The total energy capacity of the battery is 24.2 kWh, of which a portion is reserved to prevent damage by excessively deep battery discharging. The front end of the battery is equipped with a Battery Management Controller (BMC). It performs safety, diagnostic and monitoring functions and also regulates the battery’s temperature in the Battery Junction Controller (interface to energy supply for the motor).
As in the smaller e-up!, there are various ways to charge the battery in the new e-Golf. The conventional solution is to use the standard charging cable and plug it into a 230-Volt mains socket. If they were fully discharged, the e-Golf batteries are then charged with alternating current (AC) from the mains at a power level of 2.3 kW in a maximum of 13 hours (100% state of charge of the battery).
As an option, Volkswagen offers a wallbox for the garage or carport, which charges at a power of 3.6 kW; this would fully charge the battery in around eight hours.
An available 7.2 kW on-board charger works with the CCS (Combined Charging System) for DC fast charging. In this case, the Volkswagen is charged at up to 40 kW of power from CCS charging stations; they charge the battery to 80% capacity in just around 30 minutes. In the e-Golf, the start time for charging—either immediate or with a programmed time offset—is activated by pushing a button on the charging plug under the “fuel door”.
Eco’ and ‘Eco+’ driving profiles. The e-Golf is equipped as standard with three driving profiles: ‘Normal’, ‘Eco’ and ‘Eco+’. The Volkswagen is automatically started in ‘Normal’ mode. For drivers wanting to extend the range, the first option is the ‘Eco’ mode. In this case, the electric motor’s maximum power is reduced to 70 kW, and drive-off torque is limited to 220 N·m. In parallel, the electronics reduce the output of the air conditioning system and modify the response curve of the accelerator pedal.
In this mode, the e-Golf can reach speeds of up to 115 km/h (in ‘Normal’ mode: 140 km/h) and accelerate to 100 km/h in 13.1 seconds (‘Normal’: 10.4 seconds).
In ‘Eco+’ mode, the electronics limit power output to 55 kW and drive-off torque to 175 Nm. At the same time, the accelerator pedal response curve is made flatter, and the air conditioning is switched off. The e-Golf now reaches a top speed of 90 km/h and accelerates at a slower rate. Nonetheless, drivers can still obtain full power, maximum torque and a top speed of 140 km/h in ‘Eco’ and ‘Eco+’ mode by kick-down.
Driver profile settings
SettingPower outputTorqueTop speed
Normal85 kW270 N·m87 mph
Eco70 kW220 N·m72 mph
Eco+55 kW175 N·m56 mph

Regenerative braking in settings ‘D1’, ‘D2’, ‘D3’ and ‘B’. In addition to setting a driving mode, driving range can also be influenced using the regenerative braking system. Drivers can choose from five levels: ‘D’ (no regenerative braking), ‘D1’, D2’, ‘D3’ and ‘B’.
In gear lever setting ‘D’ the driver taps the gear lever knob to the left to switch to ‘D1’ (1 tap), ‘D2’ (2 taps) or ‘D3’ (3 taps). Tapping the knob to the right moves down the D levels. If the gear lever is pushed to the right and held there longer, the electronics switch back to ‘D’ in one jump. The driver activates regenerative braking level ‘B’ by pulling the gear shift lever backwards. In an electric car, this number of levels leads to a different way of driving because it is possible to use regenerative braking to intentionally slow the vehicle.
Level ‘D1’ regenerates energy and slows down the car the least, while level ‘B’ has the strongest effect. At levels ‘D2’, ‘D3’ and ‘B’, the deceleration via regenerative braking is so strong that the brake lights automatically come on. However, if the battery is fully charged, no braking energy is regenerated. This also reduces effective braking power, which the driver can feel intuitively.
Volkswagen developed a special electromechanical brake servo for its electric cars. This optimizes the driver’s braking force in the same way that brake servos do in conventional cars. However, with the electromechanical brake servo this happens by what is known as ‘brake blending’—a process in which low levels of deceleration are produced solely through the e-motor’s braking torque. Stronger deceleration, meanwhile, is achieved by combining the braking torques of the electric motor and the hydraulic brake system.
Safety. The body shell now has 28% of parts in ultra-high-strength hot-formed steel, up from 6% on the Golf Gen 6. New safety features include standard Automatic Post-Collision Braking System, which applies the brakes to stop secondary impacts in a collision.
Connected vehicle services and other features. The electrically powered Golf is the only model of the series to be equipped with the high-end Discover Pro radio-navigation system as standard. Its convenience features include the “Volkswagen Car-Net-e-Remote” app that lets users perform functions from a smart phone, e.g. to remotely start battery charging, activate the standard parking heating/cooling function (during the charging process) or access vehicle data.
Other features include the driving profile selector (“Normal”, “Eco”, “Eco+”), a heated windscreen and an automatic climate control system. Exterior features distinguishing the e-Golf include LED headlights and—a visual feature used to identify all Volkswagen cars with an electric or plug-in hybrid drive—c-shaped daytime running lights. All Golf cars with an electric motor also display a blue crossbar in the radiator grille and in the headlight housings (“e-design line”). Further features at no extra charge include LED rear lights and aerodynamic 16-inch alloy wheels.
Golf GTE
The GTE is not only a plug-in hybrid, it is also the third model in the GT (Gran Turismo) line, alongside the iconic gasoline-powered GTI and the diesel GTD.
GTE_35
Golf GTE in front of the hangar doors at Tempelhof. Click to enlarge.
The GTE shares the basic powertrain hardware with the Audi A3 e-tron PHEV; software controls will differ. The newly unveiled Golf GTE packages a 1.4-liter 150 PS (148 hp, 110 kW) TSI direct-injection gasoline engine with a 75 kW electric motor; combined system power is 204 PS (150 hp), with torque of 350 N·m (258 lb-ft). Using the electric motor alone, the GTE is capable of speeds of 81 mph (130 km/h); with the TSI engine as well, the Golf GTE can accelerate from zero to 62 mph in 7.6 seconds and on to 135 mph (217 km/h).
The Golf GTE offers combined cycle fuel economy (provisional) of about 157 mpg US (1.5 l/100 km) and CO2 emissions of 35 g/km. Theoretical range is around 580 miles (933 km). Equipped with an 8.8 kWh Li-ion battery pack, the Golf GTE can travel up to 31 miles (50 km) in all-electric mode, depending on conditions. The battery weighs 120 kg, giving the GTE a total curbweight of 1,520 kg (3,351 lbs).
Volkswagen is optimistic about customer reception for the GTE, which combines the sporty driving dynamics of the Golf GTD (the diesel GT model; the gasoline-powered GTI remains a higher-end performance option) with the low-emissions potential of a plug-in.
There are no details currently available on market introduction or pricing.
While Volkswagen has large numbers of the e-Golf and e-Up! at Berlin-Tempelhof for test drives, it had only four GTE prototypes; driving time was thus limited. Nevertheless, based on a few rounds on the old Tempelhof tarmac, the GTE delivers on its sporty target.
With all-electric drive selectable from the console, the driver can cut out the engine altogether (state of charge allowing), and function simply as an EV. In this mode, the GTE cruised effortlessly through Berlin and onto a higher speed highway with ease.

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