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Comment by tinbad | Hacker News Reader

Actually there's nothing new here, many manufacturers are moving to the 48 volt system[1], which you can classify as a mild hybrid system of some sort. Many flagship cars already have it or will come out with it soon (new Audi A8).

In my opinion, calling your whole line up of cars "electrified" is a bit misleading. But I guess that's just how PR/marketing works.

[1] https://www.extremetech.com/extreme/247889-cars-moving-48-vo...

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It should be noted that a not-insignificant amount of a vehicle's emissions come from idling. Simply reducing the time a car idles can reduce its emissions by 9%[1].

[1] http://www.urbanemissions.info/wp-content/uploads/docs/SIM-1...

Yes, but I find I disable it in my car every so often, so as to not loose air conditioning. Even on not especially warm days, the more humid air when the AC is off, feels uncomfortable.

This is one of the reasons why a more thoroughly electrified car, which uses a compressor driven by an electric motor rather than by a pulley off a serpentine belt, will be more efficient. Baby steps!

Indeed. In fact, I have not kept up very well with how cars are constructed and I was surprised to learn that there is a pulley in my car. (Volvo V60 2016.) I had assumed it would be a small electric motor powering the compressor.

I'm quite excited about 48v because it means turbos can now be driven with an electric motor until there is sufficient pressure from exhaust gases to spool them, and thus, mark the end of turbo lag as we know it!

The current model Audi SQ7 uses such a turbo-charger.

I think that's https://en.wikipedia.org/wiki/Supercharger#Twincharging because they're investing engine power (via the alternator) as well as otherwise-wasted power from the exhaust.

Kinda. The difference between this and twincharging is that the supercharger is spooled by a belt driven by the crankshaft rather than an electric motor. This means that the rotational speed of the turbine (and therefore boost pressure) is proportionate to the current engine speed whereas a 48v electric motor can spool the turbo to 30,000RPM and provide full boost pressure at any engine speed.

It's interesting to see that much of the tech described in the article come from Formula 1's latest engine formula. There was a lot of complaints about Road Relevance, clearly it has born fruit.

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