Speed limits and EVs

Where's the "like" button on this thing?!

It's probably the case that most other EVs will run out of juice too quickly at 80 mph to get anywhere. Brian, you might as well say "TESLA SPEED LIMIT" up there

@brianman

Very good idea. Are you going to set or propose these speed limits for real in the USA?

Brilliant idea. Best and cheapest way to promote EV adoption I've seen to date. Will probably do more for EV's (at least for Tesla) than the federal tax credit!

You should send it to Elon somehow.

deonb said:

You should send it to Elon somehow.

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Agree 100%

Having traffic on the same road with a legal 20mph spread will result in a 40mph spread. I suspect that would prove disastrous.

andrewket said:

Having traffic on the same road with a legal 20mph spread will result in a 40mph spread. I suspect that would prove disastrous.

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But I guess that in brianman's view the new speed limits would apply only on roads with a speed limit of 60mph.

Raffy.Roma said:

But I guess that in brianman's view the new speed limits would apply only on roads with a speed limit of 60mph.

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Remember that the word "Limit" in "Speed Limit" means "Maximum Speed Limit". I believe the "Minimum" speed limit on a 60 MPH freeway is 40 MPH. So in this scenario you could have vehicles driving between 40 and 80 MPH... not a good idea in my view.

This is what the signs look like where I live. It's amazing how many people interpret the word "Maximum" to mean "Minimum" :smile:

andrewket said:

Having traffic on the same road with a legal 20mph spread will result in a 40mph spread. I suspect that would prove disastrous.

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The spread on the Autobahn is more like 80 mph, and the Germans manage to make it work...mostly. But drivers in the US don't have the required lane discipline, IMO.

Speed limits are supposedly about safety, not fuel conservation anymore. Sure, the move from 70 mph to 55 mph started as a gasoline conservation measure, but it had dramatic impacts on highway fatalities. As @andrewket pointed out, increasing the range of legal speeds creates additional safety issues, so I don't see how the safety-focused bureaucrats who set speed limits would ever buy into this idea.

And I for another do not like the idea. While fast can be nice; it also eats significantly into fuel economy and safety. There are many ways to promote EV's but I do not think this is one of the better ones. Normally when I am on the Interstate I am driving for range and with virtually no high speed charging options, faster driving is really just a longer trip time wise.

So let's modify the OPs signage and keep the idea of highway safety and fuel conservation:

SPEED LIMIT

400Wh / mi

brianman said:

Furthermore, this would only appeal to the environmental crowd not the average driver. As such, it would be a step backwards from my intent in the OP.

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Agree 100%. IMO main thing is to address also to people that are not so much interested in environment. By setting a higher speed limit for EVs maybe that also a Ferrari owner would find it interesting to buy an EV.

andrewket said:

Having traffic on the same road with a legal 20mph spread will result in a 40mph spread. I suspect that would prove disastrous.

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I would agree. A few years ago, I read an article that listed factors contributing to accidents. One of them was speed differential - the gap between the fastest and slowest cars on the highway. Another way of putting it would be to say that slow drivers may not be involved in accidents, but they cause accidents.

brianman said:

So we should ban cars that are going 30 under the speed limit because they present a hazard? Like hypermilers doing 40 in a 70mph zone?

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I made an open-ended statement without recommendations. You can measure the gap going downwards with the fastest car as the baseline (as in the above example) or you can measure it going upwards using the slowest car as the baseline (e.g. - speed limits). It should be noted that some expressways already have minimum speed postings. Anyway, I leave the making of recommendations to those so inclined.