BMW Hydrogen 7

The BMW Hydrogen 7 is a limited-production hydrogen internal combustion engine vehicle produced from 2005 to 2007. Based on the BMW 760Li, it features a modified 6-liter V-12 engine that can run on both hydrogen and gasoline, making it a bivalent engine. Only 100 units were made, primarily given to public figures like politicians and celebrities to promote hydrogen technology.

The vehicle uses high-pressure injectors for hydrogen combustion, employing a unique ignition system combining spark and diesel methods. This achieves efficiency levels comparable to turbodiesel engines. The car can switch between fuels seamlessly via a steering wheel button or automatically when one fuel is depleted.

Hydrogen is stored as a liquid in a 170-liter, highly insulated tank maintained at cryogenic temperatures (−253 °C). If unused for 17 hours, the tank vents pressure, losing all hydrogen within 10–12 days. Critics argue this project may be greenwashing, as hydrogen production's environmental impact outweighs the benefits of reduced tailpipe emissions.

The Hydrogen 7 produces 256 horsepower and 390 N⋅m torque, accelerating from 0 to 100 km/h in 9.5 seconds. It offers a hydrogen range of 201 km and gasoline range of 480 km, totaling over 640 km. Fuel efficiency is about 50 L/100 km on hydrogen. Compared to Honda's FCX Clarity, which achieves better mileage, the Hydrogen 7 is heavier by 250 kg due to its hydrogen system.