When most people think of leak testing, one childhood event probably comes to mind: Submerging a filled bicycle inner tube in a sink full of water, hoping to find the exact leak location by following a trail of air bubbles.

ORION TOWNSHIP, MI—A General Motors Co. manufacturing plant in Metro Detroit that was idled during the Detroit automaker’s federally induced bankruptcy is now one of the keys to GM’s future, reports The Detroit News. Orion Assembly is one of two plants where GM is investing $100 million in total to retool for Cruise AV production. The other is the Brownstown battery assembly plant, where roof modules for the Cruise AV are built.

At the recent Geneva Motor Show, vehicle electrification was a leading topic of conversation. While automakers aren’t giving up on the good-old internal combustion engine just yet, they’re investing billions of dollars to develop fully electric systems that are reliable, safe and cost-effective to assemble.

The automotive industry is undergoing the biggest transformation in its 130-year history. Automakers and suppliers around the world are scrambling to develop autonomous vehicles. And, they’re under increasing pressure from outsiders ranging from Silicon Valley tech giants to startup entrepreneurs.

Whenever anyone mentions hybrid-electric vehicles today, most people automatically think of cars, buses and trucks. But, up in the sky, the technology is also getting a lot of attention from aerospace engineers. That’s because electric systems are greener, lighter, quieter and more energy-efficient than traditional alternatives.

Many experts tout fuel cells as one of the cleanest forms of green energy, because the devices reduce CO2 emissions and provide greater energy efficiency than combustion engines.

Within the next decade, a large portion of the U.S. Army’s huge fleet of vehicles could run on battery power. In fact, the Pentagon plans to acquire more than 92,000 electric vehicles by 2020.