Plug & Play car: GM EV1

The EV1 was GM’s attempt to electrify cars about mid 90’s, sold trough Saturn dealerships. It came out as a response to CARB (California Air Resources Board) that forced major car manufactures to offer a zero emission vehicle. EV1 was one of many models that came out, such as Ford Ranger EV, Toyota Rav4 EV, Chevrolet S10 EV, Honda EV plus or Nissan Altra EV (R’nessa). It was introduced at 1990 Los Angeles auto show as a prototype called Impact.
General Motors made a huge technical and economical effort to develop EV1, that turn out into a symbol that remained for more than a decade. Nowadays, when talking about Chevrolet Volt / Opel Ampera, many references are made to GM’s pioneer in electric cars and once-official EV1 website (www.gmev.com) introduces the new model of the Detroit giant without a mention to the original model.

Outside
A whole new aluminum chassis, suspension and wheels were designed for the EV1. Thus, weight was reduced to 1910 pounds (865 kg) without batteries.
Main dimensions were: length 169 inches (4’31 meters), width 70 inches (1’76 meters) and height 50 inches (1’28 meters).
Exterior car panels were made from light, dent resistant plastic and they formed a teardrop shape, where front axis was wider than the rear one, as the Citröen DS. This configuration and special low rolling resistance and self-sealing 175/65 R14 tires inflated to 50 psi (3’45 bar) contributed to a poor dynamic performance. But this body reduced aerodynamic resistance, achieving an amazing 0’19 Cx (a current Prius has a 0’25 Cx) and a frontal area of 0’36 m2. Very low aerodynamic and rolling resistances were fit together to create an excellent eco car.

Interior
It was a two-seater vehicle with a quite generous trunk for its length. EV1 interior was even more advanced than the car. It’s futuristic appearance included a huge central area with the audio system, many buttons and the gear selector. Battery, speed, range and other info was available at the center screen on the dashboard. This interior design and the feeling of moving just with rolling and electric sound created an unique driving experience.

Power system and brakes
The car was moved by a 3-phase AC electric induction motor that was able to generate 102 kW (137 hp) at 7000 rpm. The torque was constant, 107 pound·feet (149 Nm) so gear shifting was unneeded. Power was translated to wheels though a single reduction gear.
Motor management was carried out by an inverter with isolated gate bipolar transistors (IGBT) power electronics.

It made 0 to 60 mph in 9 seconds and the top speed was electronically limited to 80 mph (129 km/h).
The estimated average consumption in kW·h/100 miles was 26 city/26 highway for lead-acid system and 34 city/30 highway for nickel metal hydride (Nimh) batteries.
It was equipped with hydraulic power brakes with embedded regenerative braking and electric parking brake. Braking from 60 mph to stop was achieved in 160 feet (49 meters).

Batteries
It was available with lead-acid or nickel metal hydride (Nimh) batteries. Lead-acid battery system was worth $4800 its weight was 1175 pounds (530 kg). It was made by 26 batteries connected in series and arranged in a T shape between and behind front seats. First lead-acid system was made by Delphi, with units of 12V /53 A·h and a total capacity of 16’5 kW·h at 312 V that achieved a 60 miles (96 km) range. Generation 2, released in 1999, was equipped with a Panasonic lead-acid system, valve regulated, with 12V/60A•h units, total capacity of 18’7 kW·h at 312V that achieved a 100 miles (161 km) range. It was a 99% recyclable technology, but had a higher memory effect than Nimh.
The Nimh option was also made by Panasonic and its weight was 1000 pounds (450 kg) . As the lead-acid, it was arranged in a T shape between and behind seats with units connected in series. Each unit had 13’2V and 77 A·h, with a total capacity of 26’4 kWh at 343V, that achieved a 160 miles (257 km) range. The price of the Nimh battery pack is difficult to find, but it’s somewhere between $20000 and $35000, just as a good quality and properly equipped car. Its specific energy (kW·h/kg) doubled the lead-acid figures and, moreover, Nimh had lower degradation under high currents, lower cycling sensibility (equivalent to car’s service life) and better performance in low temperatures but worst in hot weather. The recycling process regenerates the whole product and allows the production of new batteries. But it was a very expensive technology that was supposed to reduce its price when it became a mainstream product. More than 10 years later, Toyota Prius batteries have a capacity of 1’3 kW·h with Nimh technology and the retail price is around $1500. Converting that price to the EV1’s 26’4 kW·h Nimh whole pack, the result is about $30500. So, either a much more mainstream battery as the Prius didn’t get a lower price for this technology or EV1 battery pack was even more expensive than it was estimated.
In addition to above-mentioned high voltage packs, EV1 had a 12V battery to supply power to accessories.

Charging system
EV1 could be charged by a conventional 110V 60Hz charger placed in the truck. An inductive charger was also available and it allowed a no contact charge without electric risk while acting as a transformer. But its efficiency was low when compared to the conventional charger. The inductive charger connection was located between front headlights.

Equipment
Most important equipment is: ABS, traction control, tire pressure control system, dual airbag, 3 points seatbelts, daytime running lights, keyless entry/start-up with security system, electrically heated windshield and rear window defrosting and defogging, power windows, power door locks, cruise control, AM/FM radio with CD player and climate control with heat pump.

And… how much is it?
The EV1 could only be purchased under a leasing contract, that included maintenance and service, including everything from batteries to tires, and a 3 year or 36000 miles warranty with 24 hour road assistance. Estimated retail price was around $34000 to $44000, depending on year and battery technology. Monthly leasing price was between $350 and $575. Electricity cost was from $2’5 to $3 per 100 miles, against $6’8 for an equivalent gas powered car.
But, if you want to buy one nowadays, you’ll have serious trouble. EV1 were removed in 2002. Leasing contracts weren’t renewed when reaching the expiration date and GM denied any buying option suggested by users, including the warranty or service cancellation. All vehicles were picked up by GM and crushed, with few exceptions that came to universities or museums. This generated a huge controversy in USA, that increased with lawsuits and patent acquisition in battery technology by oil companies and increasing pressure from federal government that softened legal conditions that boosted this EV fever in California. GM gave many reasons for this fact, some with low credibility and others more sensible. Anyway, the most innovative GM project was ended in a non-dialogist way while other makers such as Toyota or Ford knew how to look for formulas to sell their vehicles after leasing.

A very interesting look at this history of a huge step forward and its early death were summarized in a very recommendable documentary: “Who killed the electric car?” (http://www.whokilledtheelectriccar.com/), directed by Chris Paine in 2006. Here are the links to english and Spanish sources. The second part of this documentary has just been released: “Revenge of the electric car” (http://www.revengeoftheelectriccar.com) and it reviews how it reemerged from its ashes over last years through the efforts of 4 men to build a successful electric vehicle.

Until next post, I leave you these videos to get a deeper idea of what this iconic car meant and still means:
-Promotional video
-Commercial
-The Simsons commercial. Homer agreed to do a test drive, as Lisa requested. He concluded he didn’t like the car after driving it underwater.
-One car recovered and restored
-Some information about the vehicle and its use, including some troubles with nominal and real range.

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