He explains what those mean.

It's vehicles specialized on site-diverse way out of the city activities, like forest management and mining.

Well, I personally disagree on mining, but yes, those exist, and it's very likely they will not be electric.

Mining is actually planning on switching to electric. Mines often have underground areas where air at all is a problem, so running an engine requires extra ventilation and air quality control. Mines tend to cover limited areas, so it is feasible to have wires (either like a train where a phantograph, or drag the wire). Much of the equipment is semi-permanent so you can run fixed wires. The rest tends to run a fixed route so battery swap can be done often on schedule.

Not all mines operate in that way, but a significant number do. And of course nobody said that they had to switch 100%, some equipment can switch where it makes sense while others remain diesel.