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Comment by ZeroGravitas | Hacker News Reader

I wonder if anyone has estimated the impact of "simple" engineering changes on the progress of electric cars.

I have seen things that extrapolate out battery progress, so if batteries become cheaper/lighter/more powerful in a similar way they have in the past then that has a big impact on EVs, dropping their price and/or increasing their range.

But a lot of things seem fairly simple, if not obvious except with hindsight e.g. heated steering wheels and seats instead of air heating, heat pumps rather than resistive heating, puncture resistant tyres rather than carry a spare, led lighting, replacing side mirrors with cameras for lower drag etc. How much can straightforward, no new tech, improvements in all these areas actually help if you add them up?

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Tesla's original major innovation in this area was realizing that, if batteries are expensive, then the way to make an electric car people want to buy is to make it really expensive and really good, rather than trying to cut costs everywhere and ending up with something moderately expensive that sucked.

They don't really eke out efficiency the way you describe. They have heated seats standard and use aluminum body panels to cut weight, but it's still a big, heavy car. They're among the least efficient EVs out there. Tesla doesn't use a heat pump for cabin heating. Heated seats cut down on heating energy a little bit, but speaking from my own experience, I'd say they let me drop the cabin temperature by only 2-4 degrees (F). Energy consumption from lighting is insignificant (Tesla didn't start using LEDs until recently, I have halogen bulbs), and the weight saved from not carrying a spare tire is pretty minor. I believe they omitted it manly to have more cargo space. The main reason they go so far is because the batteries are several times larger than anyone else's (save the Bolt).

Certainly it helps. Tesla keeps pushing to replace side mirrors with cameras, as you mention, which would add maybe 3% to range. On the other hand, the Model 3 will have a steel body, since apparently cost matters more than weight there. Batteries seem to be far and away the most productive area of improvement.

> I wonder if anyone has estimated the impact of "simple" engineering changes on the progress of electric cars.

Many years ago, I was browsing through an old Hot Rodding guide to Harley Davidson motorcycles. (Don't ask why.) One line from the book that made a lasting impression was a comment to the effect that real progress was more likely to be found in one hundred 1% improvements than one 100% improvement.

As a practitioner and observer of engineering, this really resonates as something with a lot of truth. Even for seemingly transformative changes, they're backed with a long series of incremental refinements until they're actually useful. T

sounds a lot like Kaizen

Compounded growth is a powerful thing.

1% compounded 100 times = 270.48, which is way better than 100%!

And it gets even better the more steps you go:

1% x 150 = 444.84

1% x 200 = 731.6

People lament the fact that batteries "only get better about 5% per year", but compounding that means they double in performance every ~14 years!

> e.g. heated steering wheels and seats instead of air heating

The next step could be microwave heating systems that directly heat your body. But I would probably not feel comfortable with that.

https://www.wired.com/2008/01/pain-beam-centr/

Or a Japanese invention - kotatsu.

a blanket with a heater under it?

I swear it works, let me show you.

- No, no one will ever fund this

Cue the discovery of H. Pylori[1] and subsequent acceptance.

[1] http://discovermagazine.com/2010/mar/07-dr-drank-broth-gave-...

Oh yeah I was referencing the show Silicon Valley

that seems like a terrible idea?

Let me see, people are already really upset by cellphone radiations, which are non-ionizing and therefore can only be harmful from the heat it generates.

You would need marketing masterminds to sell this.

All it would take is one mommy blogger to make the connection that cell phone signals are already microwaves.

That is illegal in the US: there's a regulation that limits microwave power levels outside of an oven to little enough that it doesn't significantly heat anything.

Probably good as microwaves behave very unpredictable in the complex fat-air-water boundaries in a body.

It is hard to rule out that a focused reflection from the head accidentally heat up a part of the retina just a few degrees, which might blind someone.

Team Sky won the Tour de France and Olympic medals through continuous aggregation of marginal gains.

http://road.cc/content/feature/187025-12-ways-team-sky-devel...

My guess there is quite a lot of this low-hanging fruit improvements. Electric cars its a young technology than can go through tons of incremental changes that will add up.

E.g. compare gas cars over decades. There were tons of improvements that allow much better fuel efficiency.

>compare gas cars over decades. There were tons of improvements that allow much better fuel efficiency.

Electric motors are old technology. Most of the improvements in electric motors have already been achieved, just like the internal combustion engine.

Most of the things that original poster pointed to are improvements brought from gasoline cars (only the heat pump for heat is somewhat unique - gas engines have plenty of waste heat so they don't need that)

Air conditioners are heat pumps.

That's my point though, it's not that they invented new technology, they just sat down and said "heating is using X% of the battery, how can we lower that" and because it's an EV rather than an ICE car, different decisions would be made when picking from the existing range of off-the-shelf tech. There will be lots of these little decisions, and they'll probably add up, now that people are over the hump of "how can we build a modern EV" and just building incrementally better cars.

If you would only keep bodies warm, wouldn't you constantly have steam coming out of your mouth in cold weather? Wouldn't you have steamy windows without heating or air conditioning? What about babies in baby seats?

Plug-in baby seats.

This is the principle of the Chevy Bolt. Instead of hoping for a revolution, they went for lots of little optimizations.

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