A new UPS truck now rolling around the streets of London looks like an ordinary delivery vehicle. But at night, the truck plugs into a new smart grid at the company’s hub in the center of the city, where it pulls in enough charge to drive up to 150 miles the next day.

The smart grid and the battery infrastructure inside the truck are made by the U.K.-based startup Arrival. They will soon fully debut in a pilot fleet of custom trucks equipped with other features, including a wraparound front window that makes it easier for a driver to see other vehicles and pedestrians. This pilot is just one piece of UPS’ larger experimentation with electric vehicles.

In July, UPS announced that it was working with Thor Trucks, an L.A. startup, to develop and test another fully electric delivery truck. In February, the company announced a partnership with Workhorse, based in Ohio and Indiana, to design and deploy new electric trucks that will be no more expensive than conventional trucks. Last December, UPS preordered 125 electric semis from Tesla, the largest publicly-announced reservation of the vehicles. In a handful of cities like Portland, the company is using electric tricycles to make deliveries on some routes.

“We’re trying to make sure that we’re diversified enough that we can go in a couple of different directions,” says Scott Phillippi, the company’s senior director of maintenance and engineering. “But we do know that electrification is in our future.”

The company first used electric trucks in its fleet in the 1930s, though like others who used early EVs, it eventually abandoned them because of economics. By 2001, it had reintroduced modern electric vehicles, and a few hundred are now on the road. That’s a small percentage of the company’s total fleet of 119,000 vehicles. But technology is now at a point where much larger scale-up may be possible.

Workhorse’s lightweight vehicle, designed from scratch, is the first to be comparable in upfront cost to a regular delivery truck. The cost of electric batteries dropped 80% between 2010 and 2017, and could drop another 50% or more by 2020 or 2025, driven in part by investment in new production capacity in China. New materials that can make vehicles lighter in weight also helps reduce the battery size needed. As electric vehicles are used, they’re also cheaper to operate. Maintenance costs are lower since electric vehicles have fewer moving parts. They also run more efficiently, and are cheaper to charge than buying fuel.

In the not-too-distant future, it’s likely that most electric vehicles could be cheaper than their counterparts running on gas or diesel, though companies will also need to invest in infrastructure for charging batteries. “The zero-emission vehicle will be a positive byproduct of the right vehicle to purchase to get the work done,” Phillippi says. “What a great way to build adoption. Businesses deploy fleets based off of numbers and how that return on investment looks.”