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by djexjms 1285 days ago
If anyone is interested in the opinion of an actual CDL holder, I think the technology has amazing promise and will eventually be adopted for many kind of CDL driving. I used to work for a public utility company (water/waster water), and we had a fleet of about a dozen or so dump trucks then we used whenever we had to dig something up. These were big machines, full size tractors with a dump bed instead of a fifth wheel (the mechanism that semi tractors normally have installed to tow trailers). They also served to tow flatbed trailers loaded with a backhoe, out to the dig site.

Now these machines never left our service area. They were always parked in the same lot every night. Putting in charging infrastructure in that lot would be trivial, and would almost certainly cost less than maintaining our own diesel storage and pumping infrastructure (which we did do because it saved us so much of our working day to be able to fuel everything up in the morning instead of having to drive to a truck stop before starting the work day).

A lot of trucking is local or regional. Those will be the markets that EV makes the most sense for. Where the trucks normally go back to the same lot every night, and the owners can cheaply put in slow charge infrastructure. Could we get EV trucking working for long-haul (a kind of trucking I've also done in the past)? Sure. It will require fast charge infrastructure though. 500 miles is a lot of range, but in long haul trucking, very often you operate in two driver teams, and your truck is always moving. Fast charging could solve that too, but perhaps the solution is to reduce the number of miles that freight spends on the road. Multi-modal shipping could be expanded. Use trains to cover large distance, and try to keep road transportation of freight to the regional level and local level. This is already an option that exists. Multi-modal is already a sub-industry in trucking. This seems like the most logical option to me, but I'm not an expert. Just somebody who has lived the industry for a few years.

3 comments

Thanks for your perspective. There are lots of people who like to shoot down technologies simply because they're ignorant of all the scenarios that exist. They see only one possible use (e.g. long haul trucking), correctly identify that the technology won't work in that scenario, then proceed to dismiss it entirely because they're unaware of the myriad of other applications.

The problem with these people is that they will go to great lengths to explain to you why your technology won't work in their specific application and feel smug because they think they've cleverly identified a flaw that you didn't think of.

Even slow overnight charging will have to be pretty beefy for these trucks and their batteries though. They're going to expend significantly more energy than your commuter car so they'll have to suck down a lot of juice overnight.
In the areas that companies build their truck lots with diesel depot's there is typically significant power available. The US electrical grid has expanded at a fairly steady rate. I don't see why it wouldn't be able to handle a continued growth rate via electric trucks.

Just to put some numbers out there, the semi battery pack is probably around 850kWh-1MWh. Imagine if this gets drained every day and a company has 10 trucks, the trucks have roughly 10-12 hours to charge (~6pm to 6am). So you'd need 1MW of electrical capacity.

This is equivalent to about 20 modern US homes (200A*240VAC) and not that crazy in the scheme of things. A medium sized factory in the US probably has a grid connection around this size depending on what they do.

The grid also has lots of excess overnight capacity. From the California Independent system operator data, the state has 42,000 MW of total capacity. Overnight demand is below 23,000 MW for much of the night. Even if we exclude the top 20% of capacity as too expensive or polluting, we still have 11,000MW of available capacity today in the overnight window in California alone.
I wonder how much longer the excess in CA will be there. As we are moving more and more towards solar we need more storage to handle shadow and the loads at night.
It's certainly doable but it's not going to be cheap at all. That's at 1300 amp service of 480v 3-phase just for charging plus the chargers to handle that ~100KW of load per truck, to provide that power you're likely going to have the external charger setup instead of just one on the truck itself and those aren't cheap.
If the numbers work, they'll do it. It's not like they're going to get 95% of the way through the design process and then give up because power delivery costs a little more.

If the ROI is there, they'll do it. If it's not, they won't.

Well yeah my point is the ROI is pushed out because of the extra expense of the install and acquiring sufficient electrical service above and beyond the cost of the new fleet.
No, but installing an maintaining diesel tanks and pumps ain't cheap either! Especially if you have to deal with any environmental destruction caused by spillage or leaking tanks (happens way, way more than most people think).
Battery swapping seems like it circumvents the slowness-of-charge problem, both for short haul (port and local urban service) and later for long haul. (Dealing with detours on the latter could be tricky though.)

5 - 10 minute battery swap vs however many minutes charging. Sure it reduces the load carrying capacity and/or range a bit, but it should still be viable for many heavy goods vehicles. Swapping makes it easier to manage battery condition and vehicle utilisation. Over time battery provision/swapping could be outsourced, so the transport company can focus on trucking, not on batteries and their needs.