Joule - South African Slow Jam

images from Optimal Energy


  • Type: Dedicated electric vehicle
  • Class: Six-seat urban MPV
  • Manufacturer: Optimal Energy Ltd
  • Propulsion system: Two options: 1) Asynchronous permanent magnet motor driving the front wheels through an 8:1 reduction gearbox, 2) Asynchronous permanent magnet motors located in the wheels, for rear or four wheel drive.
  • Top Speed: 84 mph (135 km/h)
  • Zero-to-60: 14 seconds
  • Vehicle range: 124 miles (200 km) per battery module (total potential range: 248 miles/400km)
  • Fuel(s): Electric
  • Battery system: Lithium-ion
  • Time to full battery recharge: 7 hours using 220V outlet per module
  • Price (excludes battery): Est. $26,000 (R200,000 South African Rand)
  • Monthly battery lease: Est. $193/month (R1,500 South African Rand) per module
  • Availability: 2010 in South Africa

The manufacturer says

"Joule is not only sleek and sophisticated, it comes standard with all the expected modern conveniences including blue tooth compatibility and iPod functionality, making it practical to boot."


The Optimal Energy Joule might be the sexiest and best-performing model to emerge from South Africa since Charlize Theron left the old mining town of Benoni for the runways of Milan.

Cape Town-based and privately owned Optimal Energy (Pty) Ltd was founded in 2005 thanks in part to a government investment from South Africa's Innovation Fund. Co-founder Kobus Meiring is the company's CEO and was previously in charge of the SALT (Southern African Large Telescope) program.

Like the 2010 Prius, the Joule has an optional roof solar panel that can power a few blasts from the AC or juice the battery for an extra mile or so. A steel space frame and composite (glass and carbon) and plastic body panels make up the Joule's body, and its chassis has a flat wafer structure, which the maker credits for giving the Joule's interior so much space and flexibility.

What we like

The design. When you're a start-up car company looking to get some attention, hire a distinguished name in vehicle design. If he's local, all the better. That's what Optimal Energy did, hiring fellow South African Keith Helfet, former Chief Stylist for Jaguar and responsible for the XJ220, among others. His design for the Joule is a shape-shifting gem, using lithe, graceful lines to bring together the better elements of a hatchback, mini-van, and an SUV.

joule rear

The battery option. In one of the better innovations seen so far in an electric car, the Joule's chassis was designed for either one or two lithium-ion battery modules. Just one of them gives the driver a reasonable 125 mile range for a vehicle this size. Add another, double your pleasure.

What we don’t

The claim. Optimal Energy claims the Joule has "sports-like acceleration from standstill." Name another sporty vehicle that requires 14 protracted seconds to reach 60 mph.

The leasing plan. Optimal Energy intends to sell the vehicle and lease the battery modules. There's plenty to be said in favor of leasing the battery, but early price estimates of both the Joule and the monthly lease seem to make this an especially costly route. The cost of the Joule itself needs to come down before this becomes economical.

The six seats. Three bucket seats in the front? I oppose the three bucket seats in the back so I especially oppose three in the front. News flash, fellas: this ain't a limo, where everyone deserves a pretty good seat. Some folks need to ride bitch.


There is the remote possibility that the Joule might reach US shores in 2012 or so, but there's no reason to hold your breath. It has to succeed at home first, where the market is too small to imagine generating the kind of revenue necessary to launch the vehicle outside the South African market any time soon.

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