Rivian partnered with ABC’s medical drama “Grey’s Anatomy” to custom build an electric ambulance for the show’s 22nd season, marking what producers say is an effort to start a trend toward zero-emission emergency vehicles. The Shondaland-produced series worked with Rivian to convert one of the EV maker’s commercial vans into a functioning ambulance, replacing the diesel-powered vehicles that had been used on set for 20 years. Rivian has been expanding its commercial van business beyond its consumer electric trucks and SUVs. Amazon is the EV maker’s largest shareholder and co-developed a delivery-focused van been the largest customer for the company’s electric delivery vans as part of a partnership announced in 2019. The retail giant ordered 100,000 electric delivery vans scheduled for delivery by 2030.