This thread is a perfect example of why I don’t open any links or even you tube posted video’s on open web sites.
Do you mean one like this, that plugs into the cigarette lighter and heats the inside of the car? I had never heard of them when I lived in Anchorage.
I’ve never been to Alaska, but they’re popular with truck drivers who run generators at night rather than idling the truck. I’ve never bought one myself, but I’ve seen them on the shelves in just about every truck stop north of Florida.
Maybe yes, maybe no.
After all, the most recent scam phone calls that I have gotten from people claiming to be from The IRS and from Microsoft were both voiced by people who could barely speak English.
Luckily for them, I did my best to teach them some new words in English. You know…words with only 4 letters!
I think that many spammers–like phone scammers–think that they are smarter and more proficient in English than they really are. In other words, they would need to be a lot smarter than they actually are in order to realize that they’re not so smart.
Given the nasty source of the link, it might not have been spam at all, but a link inserting malware. In that case the poster couldn’t care less about their grammar. Who knows?
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Don’t they use generators with inverters that can power a 115VAC heater and isn’t that what they use???
I’ve never been a trucker, but it would surprise me if someone running a generator would use a heater designed to plug into a cigarette lighter.
That’s an interesting question. My working theory is that having an electric heater that can use either power source (AC or DC) would be best, especially since a lot of diesel tractors struggle to generate enough heat to heat the inside of the cabin in the coldest weather. Many appliances sold for use in commercial trucks can use either AC or DC. My TV was one.
A generator setup in a semi is probably similar to a generator setup in an RV, where running the generator automatically keeps the batteries charged, so you could still run the heater on the 12 volt outlet while running the generator. The company I worked for was too cheap to put generators in trucks, so my truck never had a generator. It had an idle system that would start up the engine to run the heater or air conditioner intermittently, so the only place to plug in an electric heater or an electric cooler was the 12 volt outlets. The idle system in my truck worked kind of like a generator, because it would also start itself up to charge the batteries when they got low.
Using an inverter to convert DC to AC is an inefficient process. In fact, if your appliance’s power supply converts AC to DC, you would be converting DC to AC with the inverter, and then AC back to DC with the appliance’s power supply, a very inefficient process. It’s more efficient to plug in a DC device that doesn’t need an inverter to a 12 volt outlet. In fact, you can buy a universal DC power supply that will give you the output your device needs, but straight from the 12 volt outlet to the appliance.
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Good points, whitey.
I have to suspect that there are self-contained generator/heating units designed for sleeper cabs. I tried looking, but not knowing what I was looking for I was unable to find anything. Is there a trucker in the house? 
Modern inverters are actually surprisingly efficient. A lot of the new technology generators for camping actually generate AC at a very high frequency, 400Hz or so depending on the RPM of the engine, rectify it into DC and then have an inverter convert it to 60 Hz AC.
These generators actually consume less fuel than simple alternators that generate 60 Hz AC directly, especially at part load simply because the engine rpm is not married to 60 Hz and doesn’t have to sit there and run at a full 3600 rpm even when it is only powering a radio.
The inverter generators engine rpm is independent of the output frequency and the engine rpm can be optimized for the power actually being provided. Like putting a car’s transmission in a deep overdrive when you are on a level highway instead of always having it in a passing gear suitable for the steepest hill you will encounter.
Yes, which also supplies 120V to outlets (at least in the RV’s I’ve been in) for running a, say, 1500W heater.
The only built-in heaters I’ve seen in RVs burn propane to generate heat and have blowers, thermostats, and control systems that run off the house battery (DC). Since running the generator charges the house battery, the heating system will run off the generator, but only indirectly. This propane/DC setup allows RVers the option of boondocking off the grid in cold weather without running the generator.
You can run a 120V space heater off the generator, but you’ll burn a lot more gas doing it. When I turn on a device that uses a lot of wattage, like a rooftop air conditioner, I can hear the generator boost its idle speed to compensate. If I was at a campground connected to a 30 or 50 amp electrical connection, I’d save my propane and run an electric heater, but it’s more efficient to heat an RV with propane/DC than it is to use the generator.
The generators in semis and RVs might be similar, but I don’t think the heating systems are similar at all since I’ve never seen a commercial truck that had a propane tank attached.
@Whitey The generators used on semis run off the trucks diesel tanks & also keep the battery"s charged. You can either use 12volt or 110volt heaters.
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Thank you, Captain Obvious. I wasn’t referring to the propane heaters.
Here’s a company with products to keep a trucker warm, including a diesel-fired heater and 12V electric bunk pad:
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Running a generator in order to electrically heat a camper is actually insanely inefficient. You’d get more heat by putting the generator inside and the heater outside and using the waste heat of the engine to heat the camper.
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Car Talk Lackey
Portable 12V Car Heaters
The best, safest alternative to your factory heater is a 12V heater that’s specifically designed for automotive use. However, you’ll typically find that the ones that are designed to plug into your cigarette lighter won’t put out enough heat. That’s due to the fact that accessories that are plugged into the cigarette lighter receptacle can only draw so much amperage (typically 10 or 15 amps) without blowing a fuse.
Larger 12V car heaters have to be wired directly to the battery (typically with an inline fuse for safety) in order to draw enough power to put out the kind of heat you need during the cold winter months.
As to how well these heaters work is concerned, your mileage is going to vary. They typically don’t put out as much heat as a factory heater, but if you temper your expectations, you shouldn’t be too disappointed. Of course, you still have to think about how much power the heater is drawing. If your alternator isn’t up to the task, you might be better off just saving up enough money to fix the problem right.
There’s a company called Gerbing that makes a large line of 12 volt heated jackets, pants, gloves etc mainly marketed to the motorcycle rider market but they also have 7.2 volt rechargeable lithium battery clothing for hunting or football stadium use. It takes a lot less power to heat your clothes than it does to heat the entire cab.
There might also be 12 volt electric blankets if you just want to sleep warm while using a fraction of the power needed to heat the entire cab.
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Seems to me the best option is the old VW gas heater I had in my bug. Sure it used gas out of the tank but would drive you out with the heat it put out. I have no idea if anything like that is now available after-market but seem far more effective than an electrical heater. Actually when I drove around the state in the winter, I used to carry one of those fish house propane heaters for emergency use. Sure you had to be careful of the exhaust but would heat a fish house on the lake ice.