Hacker News Reader

Comment by idiotsecant | Hacker News Reader

In my area of the country there is one very simple modification manufacturers could make to ensure their vehicles are wildly more useful: add diesel heaters. Heat the batteries and the people during the winters rather than using onboard power to do it. It would sip diesel and contribute hugely to utility. I am in the process of building my own because nobody makes one

View on HN

Why? A lot of EVs these days comes with a heatpump so heating doesn’t use that much power. I live in a cold country where 98% of new cars are EVs and I have never heard anyone asking for something like this. A quick search on popular EV forums shows a few threads from 2010-2014. That’s it. I know webasto has a product like this, but there’s practically zero cars on the road with it installed.

Heat pumps are mostly useless when it is minus -20 C. Diesel heater is the most practical solution. Sodium or LMFP batteries will help, but even with them the range reduction in winter due to the need for heating and increased drag from cold air is just too great.

> Heat pumps are mostly useless when it is minus -20 C.

Two-thirds of households in Norway are heated by heat-pump, so I don't think that can be true.

you're not making the point you think you are. The average January temperature in most of Norway is about 10 C higher than in most of Yukon and Alaska. Norway just isn't that cold.

That said, heat pumps absolutely do work in -20 C. I would know because i have two at home and one in the car. All three worked just fine at -25 C this past winter.

I meant in heat pumps in cars due to size constrains. For homes there are heat pumps that work even at minus -30C, but one just cannot fit that into a car.

And I really do not get why there is no even option to have a diesel heaters in cold climates. It adds like 100 kilometres per long trip for a litre of fuel when it is cold and allows to use smaller and cheaper battery in EV.

How many homes have heat pump as their sole heating?

That's a useless statistic without knowing if it's their sole heat source. Just based on costs, I'm betting there's a lot of wood stoves and pellet stoves kicking around.

diesel fuel itself needs to be heated at -20 C and below. I used to have a diesel car which would start itself up periodically when its fuel temp was getting close to -20 C, just to warm up the tank & pipes.

Yeah, the 1999 diesel truck I had did the entirely opposite thing: it had a 120v electric block heater, so you'd plug it in when it was cold. (In New England, I used it once to see how it worked, but never actually needed it in practice.) At the time I saw stories (I never confirmed in any depth though) that Minnesota had 120v outlets on parking meters, giving some sort of weather-encouraged compliance :-)

Ok i get that some people really do need to deal with extreme temperatures regularly, but it totally misses the point when discussing a mass market car like the Corolla. It’s like asking business casual footware to be equipped with crampons for when you need to walk up a glacier.

The point of diesel heater is to remove the need to plugin hybrid in many cases and just go with EV plus heater.

if you get into standstill traffic in the winter, it's actually life-threatening not to have alternative power source that can warm up the passengers (and the battery). One interstate road I'm driving sometimes, has many abandoned Teslas sitting on the side of the road after a sleepless night of staying in traffic during some snow blizzard...

No different than gas vehicles running out of fuel.

Do the math and let's say theres even 50 percent charge of a 60kwh pack...and you just blast a 1000w of heat constantly....thats still 30 hours of heating at 1kw of power lol.

Gas vehicles burn .25 to .5 gallons per hour so uh...that 16 gallon tank completely topped off is 'only' 32hours. Half the tank and down to 16hours.

Just as a point of contention. Its hard to find an EV that is only gonna pull 1000w using the heater.

My EV doesn't have a heatpump and the resistive heating pulls up to 8KW warming up the cabin on a cold day.

I keep a 12v heated blanket around to save power. (no heated seats/steering wheel)

Heated seats are where the real power savings come in.

Webasto would like to have a word. "..can operate for up to 22 hours on less than one gallon of fuel.."

https://www.webasto.com/en-us/choose-vehicle-solution/oil-an...

Those are aftermarket products for use in heavy vehicles, not something that's present (or usable) in passenger cars.

They are pretty common in passenger cars too, google 'standheizung' or 'stationary heater' and you'll find a ton of them. You might not realize that that is what it is. On cars sold in the Nordics and some German brands it is just a checkbox during the order process.

It's quite normal in colder climates, but mostly in Diesel cars. I had it in my VW Multivan. I've never heard of anyone installing Webasto in their EV.

There are all sorts of China knockoffs of them going up and down the size scale.

It's amazing how comparing 1kw of power to vastly more than 1kw of power results in skewed results!

Every ev already has this today, 10 years ago it was in some leading cars like teslas. Only the leaf and a few others didn't have battery heating and cooling, and the fact that so many think those problems are in all evs set back the whole market.

A 10 year old tesla can heat and cool the battery before leaving, you could set a daily time to heat it up, or just turn it on just before you go manually if you wished.

This feels like something that would be offered by US/Canada manufacturers as a niche option, and nowhere else. Norway seems to be coping just fine without it.

(China also has regions of extreme cold; it would be interesting to see how regional EV adoption/adaptation has happened there)

In high school, one of my friends had a VW (air cooled) with a torpedo heater installed that would heat the interior to 30 degrees C in a matter of minutes - no matter how cold it was outside.

Likewise, in university, my friend's army jeep had a gas heater that would melt snow off his canvas roof.

People are consuming 30% of their battery power to heat the vehicle and batteries - and that's with reduced battery range. It only makes sense to add a container for gas/diesel and a heater - really can't understand why manufacturers are against instant and very low cost heat as an option to protect range and increase safety (in case you're stranded in the winter with a depleted battery).

Best of luck adapting one to your vehicle.

It spends some battery, but my electric car heats much faster than my diesel cars ever did. Why on earth would I use a diesel heater that’s more expensive to run and slower?

Manufacturers don't do torpedo heaters outside of campers because they are a PITA. You need to find a place for the fuel tank and the fuel receptacle, for the heater itself, and you need an exhaust that requires clearance. And for a heater integrated into regular airflow routing it gets even more complex.

Indeed - both heaters (torpedo and whatever the jeep had) blew hot air "around" and were not integrated into the vents. I think the jeep unit just drew from the gas can - not sure about the torpedo heater, but they were very economical for the amount of heat they produced.

-40 (air temperature - not windchill) is nothing to mess with. The instant heat from a battery pack is great if you're always close to charging, but there's absolutely no way I'd head into the wilderness in winter with just an EV.

Sounds like a stock EV is not for you, or the very close to 0% of the world's population with similar needs.

That's ok.

Certainly it uses some battery energy to do that battery heating. If you have a plugin at. home, even a 120v one, you can just use your home power.

just a caveat - some EVs, like Hyundai models, require using an app and the internet to enable this. If you use only the key fob, the heat pump compressor does not run.

Volvo's first electric car had this, I always thought it was neat (I rented one a few times through a car sharing service that had them) https://en.wikipedia.org/wiki/Volvo_C30#C30_DRIVe_Electric_(...

Webasto. They make a really decent little unit, easy to integrate too.

EVs should always be plugged in. There is electricity wherever it is parked. Heating or cooling can be done using grid, instead of onboard battery.

EVs play a role in the energy ecosystem. They absorb excess production during the day and can supply power back to the grid by participating in a virtual power plant (VPP).

I have been waiting for a manufacturer to finally embrace this tech. I know electric buses already do it. I think people just have a mental barrier about this because EVs are supposed to be eco friendly.

I really hope you succeed

You mean wood pellet heaters. Then you can pretend it is CO2 neutral.

Reply on news.ycombinator.com