Elon Musk introduced the company's new electric-powered tractor trailer. The Semi goes 805 kilometres on a charge, uses Tesla's semi-autonomous driving system, with lane keeping and auto braking. The truck has lower centre of gravity than traditional haulers, dramatically reducing rollover risk; dynamic torque distribution lowers the chance of jack-knifing. Musk also introduced the second-generation Tesla Roadster. The $200,000, all-wheel-drive supercar goes zero to 100 kilometres an hour in a mind-blowing 1.9 seconds, making it the fastest production car on record.