Video: Utilizing A Combustion Heater In A Fully Electric Car – A User’s Story

FEB 27 2014 BY JAY COLE 50

It’s below freezing outside, you own an electric car, you have a distance to drive that is close to your vehicle’s maximum range.  What do you do?

Yupe, It's Another Cold One!

Yupe, It’s Another Cold One!

For most the choice is simple:

  • transform into you super alter ego – “Popsicle Man” while you conserve energy
  • incorporate a little detour to a public charging station
  • hop in you 2014 Land Rover Range Rover Sport instead

Or, as demonstrated by commenter Stanislav Jaracz in New Jersey, you can install a diesel/petrol combustion heater for less than optimal plug-in driving days.

All the heat you want – all the time; and according to Jaraczs when used in a Mitsubishi i-MiEV, up to 75% more range on those extreme cold days over using your factory heating system.

In addition to the video Stan was kind enough to pass on some backstory on the heater and his experiences with the Mitsubishi i-MiEV:

My new (improved) Winter Driving Experience

It is well known fact that EV’s have shorter driving range in cold weather, as much as 60% lower. Residents of California may not know (or feel) what I am talking about but here in Northwestern area, my fellow EV drivers know what I am talking about as this Winter has been particularly rough. And then come our Northern Canadian brothers with even lower temperatures. Let me throw a question: What source of energy do we use to heat our homes?

Stan's i-MiEV Waits To Be Driven In 21 Degree New Jersey Weather

Stan’s i-MiEV Waits To Be Driven In 21 Degree New Jersey Weather

According to National Geographic, nearly 60% of homes in the US are heated with natural gas, followed by electricity and oil. In addition, the US Census 2000 shows the colder the state the bigger proportion of heating oil. Electricity is used mostly in warm southern states such as Florida.

How come that we heat our poorly insulated EV’s with electricity stored in precious battery packs? According to US Energy Information Administration, coal and natural gas fired power plants make over 2/3 in the US energy mix. These fuels are burned and the heat is converted to electric power at 30-50% efficiency, then transmitted to our homes while loosing around 6.5% and then losses during battery charging/discharging cycle. And then we convert the electricity back into the heat in our EVs. So, what is the reason we waste electricity to heat our EV’s?

I was determined to eliminate the inefficient energy conversions / transport and burn the fuel right in my EV. This would also disconnect the competition between energy use for propulsion and heating, which would significantly increase driving range in Winter, while keeping all passengers warm and cozy.

Getting Ready To Heat Things Up!

Getting Ready To Heat Things Up!

My EV (Mitsubishi iMiEV) had a liquid heating system based on the gasoline sibling and to compensate for the lack of the ICE waste heat, the Mitsubishi engineers opted for PTC heater located under the floor. After reading blogs on and searching online, I have learned about parking heaters used in cold climates to keep truck cabins warm while saving fuel and engine wear & tear.

The major brands are Webasto and Espar. I was able to identify local distributors for each of these brands and obtained pricing and availability. However, paying over $1,000 prompted me to search for cheaper alternatives. Finally, I have taken the chances and ordered “generic” JP diesel parking heater, direct ship from China. Actually, this was a complete set including all brackets, bolts, wires, mini-timer, muffler etc.

I have made a plan for the installation but it had lots of unknowns. How do I anchor the heater? How do I wire the heater control? Can I incorporate it within the vehicle climate control? Several tests had to be done before comitting to remove the old PTC heater and install the new diesel heater. And, I would not be able to make it without the help of my fellow blogger John Annen who sent me detailed vehicle manual and gave me advice on a wiring solution.

To cut the story short, I was pretty lucky and replaced the heater in one day. The dimensions of both heaters were similar and I was able to utilize original brackets to bolt the new heater into the same place. Later, I have modified the wiring and heater control to be independent of the vehicle climate control as the operation was more reliable.

Burning Diesel To Heat The i-MiEV On Those Cold Days Enables Much More Available Range

Burning Diesel To Heat The i-MiEV On Those Cold Days Enables Much More Available Range

My first impression was not so positive because the heater produces characteristic diesel odor. Before I realized that it is happening only at the start (and at shut down) I was experimenting with (bio)ethanol as a fuel. Although the heater still works with ethanol and it is essentially odorless, the performance (or Btu) was significantly lower. When I figured the smell is only temporary, I switched back to diesel.

The heater has two power stages, 2.4 kW and 5 kW. It starts at full power and when the heater fluid reaches 176 F (80 C), it adjusts the power stage to maintain the temperature within a defined window. The percieved heating intensity in the cabin is much greater compared to the original PTC heater and for most of the time, the lower power stage suffices.

Saving the battery power for propulsion significantly increases driving range even at very low temperatures. I was also able to direct the warm air into the battery pack to improve the battery performance as well. So, on a day when the temperature is 21F (-6C), the fully charged vehicle showed me 87 miles available. With the PTC heater, it would be maybe around 50 miles. The range estimate is much more similar to Summer, maybe 95 miles with the same driving history.

So, we can say that the diesel heater reversed about 80% of the Winter negative effect. And what is the (fuel) cost? The lower stage consumes 9.1 fl.oz./hr (0.27 L/hr), which translates into 380 MPG at my average speed of 25 MPH. In reality I am just finishing the first 5 gallon diesel can after 1700 miles. Having the vehicle modified, I can continue using it for the same (long) trips I got acustomed to in Summer, avoiding the use of ICE second family car.

In conclusion, my new Winter driving experience reasures me that the best way to heat the cabin and battery of an EV is via combustion process and electric powertrain is the best technology for propulsion. And, the heating does not have to come from a fossil fuel, it could be biodiesel, bioethanol, compressed biogas/syngas. I like to draw apparently unrelated comparison. When electric starter was introduced into ICE cars early in 20th century, it greatly enhanced value and practicality of ICE vehicles. And it was an inspiration from electric car. Similarly, combustion heater is an inspiration from ICE and it greatly enhances its value.

Stanislav Jaracz is a native of Czech Republic (former Czechoslovakia) and he came to the USA in 1998 to pursue study at graduate program in the Department of Chemistry, Columbia University in the City of New York. He has settled in NJ in 2007 working in consumer products industry as a technology professional. He began to think sustainably in 2010. His house is fitted with PV solar roof and high-efficiency natural gas-heat pump hybrid heating system. Influenced by the famous “Who killed the electric car” he acquired 2012 Mitsubishi iMiEV in March 2012, the first iMiEV sold in the NJ state.

Hat tip to offib!

Categories: General, Mitsubishi


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50 Comments on "Video: Utilizing A Combustion Heater In A Fully Electric Car – A User’s Story"

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I like the way this guy thinks!!

Does the i3 use its REX waste heat for cabin or batteries in cold weather?

The i3 uses a heat exchange pump just like the Renault Zoe and 2013/14 Nissan LEAF. Instead of the energy-intensive induction heaters that’s the biggest culprit of range decreases in winter, the i3’s, LEAF’s and Zoe’s heater is like a “fridge in reverse” as it’s commonly described. They’re 3 times more efficient than the old ones.

I assume that the REX won’t, just to keep weight increases at a low and probably price as well but cost cutting is an unlikely feature of any BMW.

No it doesn’t. You would think there would be some way to use that wasted heat, but since the REx is optional, that would require a bunch of coolant piping, etc., that isn’t present in the electric version.

Not only does the i3 REx not use waste heat to warm the cabin, it has only an inefficient PTC heater. The heat pump comes only with the 100% electric i3.

I believe this is due to not enough space under the hood.

I thought about using a propane heater, but decided it was just not safe.

Before I read this article and learned about the existence of parking heaters I had considered a 10x8x5″ domestic kerosene unit. If it’s safe enough for home air, it shouldn’t be too too bad for a cabin space. I guessed I could anchor it to 2 2x4s placed on floor running under the passenger side seat with no danger of falling over.

I hate the smell of kerosene. I was thinking a Mr Heater Big Buddy propane heater somehow bolted to a piece of plywood sitting on the passenger seat pointed right at me. They’re catalytic and run very clean, and you’d only need to crack the window or occasionally let in a little vent air to keep from suffocating.

The Scandinavians, who know a thing or two about cold weather driving, have produced several models which made use of supplementary kerosene heaters.

Volvo C30 EV has optional ethanol heater. Though, C30 EV has had limited production as Volvo does not believe that electric vehicles could be competitive, so they do not like to even try.

The Renault Kangoo Z.E. has a 5kW diesel heater. The old and new Peugeot Partner and Citroen Berlingo Electrique also have them, but we know so little about them so there aren’t any known specs.

Pure EV’s that is. They believe in PHEVs and in 2015 and 2016 most of their models will be electrified with a PHEV option.

Well, to be honest they do believe in pure EV’s too, but as a small car company they can’t take that risk before the market is more mature (especially on home soil where they sell a lot of their cars and where the EV market is almost non-existing yet). Until then there will only be the test fleets of a few hundred EV’s.

I would love to see a flex-fuel heater option be offered for some of the mass market EVs in the US. Unfortunately, I can see this somehow impacting the ability to get the white HOV lane sticker in California. Even though it provides heat and no propulsion.

Webasto already makes an ethanol heater for sale to vehicle manufacturers. I wonder if this Webasto heater is the one found in the Volvo C30 EV.

According to the SAE, an EV with a fuel based heater would still be a full EV (and not a hybrid). That’s because the fuel isn’t used for propulsion. I would assume CARB would still honor that definition.

The CNG civic still gets the white sticker so there is hope.

And even if they didn’t give the white sticker with it then it would be easy enough to make room for a heater, have it as something you could buy later and retrofit.
A lot of cars up in the Nordic countries come prepared have it that way so you could add heaters later on.

This is good remainder how simple it is to fix the cold weather performance issue with electric vehicles. Diesel/kerosene/ethanol/methanol heaters are not too expensive.

This is the general problem with people that they are are critizing electric vehicles that they have poor cold weather performance, but they utterly fail to see how simple this problem is to fix. When critizing something, people should always think how to fix the problem. Sometimes the fix for the problem is too simple that people are blind for it — like in this case had been in several occassions!

BTW, insurance company may not like the idea to have a plastic bottle filled with Diesel in the frunk! Therefore these kinds of do-it-yourself -solutions are somewhat problematic.

Thanks, Jay! I’ve been itching to read this all week!

Thanks for the tip, letting us get in touch with Stan about his heater, (=


This is perfect. Organized electric energy from any source for organized travel in a line, and combustion for disorganized heat. Heat is 100% wasted energy in a drive system, and heat is 100% efficient energy (for a given level of cabin insulation) in an ice cold cabin! I didn’t know these discrete automotive combustion cabin heating units were made! All makers should have them.


I’m not sure what you were trying to say at the beginning of your comment, but if it was to suggest that extracting only heat from burning fuel is the best one can do… Well, we’ve been there before:

This should be a factory option for EV’s in colder regions. BMW puts Webasto heaters in some of their diesel powered cars in select markets. They could drop one directly into the non-REX version right where the REX engine would go, and use the REX fuel tank to hold the diesel.

Eww diesel. I might consider something like this if it used a cleaner fuel, I know that volvo has been using ethanol to heat their ev.

I have a 2013 nissan leaf and live in a very cold state, but the new heat pump works really well when combined with the seat heaters and heated steering wheel.

The dirtyness of diesel (which is essentially the same as kerosene, fuel oil and jet fuel) is that the high temperature in a compression ignition engine result in the creation of nitrogen oxides, NOx. I don’t know what the best fuel for an EV space heater would be (alcohol, propane, gasoline, fuel oil, etc.) but it is far more environmentally sensible than wasting electricity in a resistance heater (except for the seat heater!).

I don’t really understand why heat pumps for heating aren’t more common in EVs given that there is already a cooling one there and making them reversible is totally commonplace. So a heat pump for cooling and heating (and defogging) down to a certain level and then a fuel fired heater for real cold conditions.

I like the blurb about how he was inspired by Who Killed the Electric Car. That movie made me so angry, and really inspired me, first to start biking to work, then later to lease a Leaf. Hey Jay you guys should do a an article on the far reaching effects that movie had, maybe on the anniversary.

I think this solution is great. I’m reasonably sure that on a 50 mile trip in an i-MiEV the quantity of fuel used is less than a 50 mile trip in a Volt.

I think this is a great idea, and I’ve often lamented that using the ICE in the Volt is an inefficient way to turn gasoline into heat. But, I would like it much better if it ran on gasoline instead of diesel. It only uses a small amount of fuel, so it wouldn’t matter if it were slightly less efficient, but gasoline is much more available than diesel. I definitely wouldn’t want propane, since that would involve swapping tanks. A gasoline heater would make the absolute most sense in a EREV like a Volt or i3, since you already have the fuel on board.

I want this, I want it now.

Well, in a purist sense the ICE of a volt is an inefficient way to do heat, but it is also heating the battery besides the cabin. I’m pleasantly surprised how little gasoline you actually use on a cold day compared to if you are forced to use the battery.

You can’t have it both ways: People here tell me (big experts no doubt) that my Volt can’t be using so much battery power in stop and go driving. But all that is eliminated when the engine starts… Driven carefully, the car sips fuel instead of gulping it down.

Actually, an ICE could be a very efficient way to produce heat, because it also extracts energy in a much more valuable form (motion or electricity) from the fuel you’re burning. Think cogeneration.

Now, measures beyond the current typical engine implementation in vehicles would need to be taken to better capture that heat, especially from exhaust gases.

That’s why Car Washes, Hospitals, and Hotels commonly use Natural Gas generators for cogeneration. All 3 establishments can use the waste heat for water heating (one large Car Wash chain until recently didn’t even bother to put in a utility electric service to their establishments).

So how come no one likes my idea of taking all those otherwise Grid Hating Tesla Superchargers, and colocating them with a cogeneration style generator? Since most generation is going to be by Natural Gas anyway, I would think people would applaud using methane more frugally, and there are seldom demand charges on Natural Gas Service.

Hmm, cogeneration surely makes sense for a carwash etc, where both heat and electricity (and/or motion, for blowers etc) are needed on the same site, and at about the same time.

I don’t see how this applies to quick-chargers at all. What to do with the heat?

Feed it to an adjacent building? First, it better be large (ie, commercial space), because a single car charging could mean having 100 to 200kW thermal to use.
Next, occupants might object having their comfort dependent on quick-charger usage, so said building would still have to have its own heater… so it’d make much more sense to just cogenerate there instead.

“What do you do with the heat?”

I was thinking in a hospital setting where the Executive Decision has been made to mostly use the Emergency Generators as a ‘power failure’ contingency, that they could also run the generators to power a colocated supercharger installation.

When an emergency occurs, the supercharging would stop and the generators would power what is originally intended.

But granted, the whole idea might not be seen as that compelling. Unless you live in an area like Southern California Edison where they charge $20/kw per month.

Some communitites are revisiting District Heating. The way Buffalo, NY does it (as well as the downtown areas of Cleveland and Akron) is pretty dumb in my opinion. They just have Natural Gas boilers, and send either Hot water (buffalo) or steam (ohio cities) into the street.

The way Edison envisioned it, DH would improve the efficiency of power plants by moving the condenser over to the ‘distributed facilities’ of homes and businesses.

Let me explain the ‘dumb’ part. at least as far as buffalo is concerned. There are a section of city-owned buildings in Downtown Buffalo that were either converted and/or built in the 1960’s for Electric Heat (!!!!). (Electricity at the time was cheap and getting cheaper, but for various reasons, mostly political, this was not to ultimately be – as electricity in this area is now quite pricey).

What’s a city manager to do? The new buildings have no boiler rooms, so how do we heat the things, and the electric bills lately are eating us alive! Put a couple of big boilers in the Fire Dept headquarters, run a supply and return hot water piping in the streets (and even though we pay electricity for the pumping its a better deal then heating a skyscraper electrically in a Buffalo winter).

So even though Dumb, it had to be done to make lemonade out of a Lemon.

I took the same cue with my 8 x 10 hot tub. A few months of paying for a 5500 watt heater was all I needed to convert. I bought a Gas boiler and an energy efficient pump (220 watts for 30 gallons per minute at 14 foot head), and its a cheap solution using 4% of the electricity when the heater is on, and since the heater is 6 times bigger than the electric one, the pumping electricity expense is less than 1% of the previous electric usage. Saves the juice for my 2 cars.


What you want for your Volt is a gasoline “air heater,” as opposed to the diesel “coolant heater” that Mr. Jaracz installed into his iMiev. An air heater can be used in either a BEV and in an EREV, while a coolant heater can be used on an EREV, but it can’t be used on any BEV except for the iMiev. An air heater directly heats air and a fan pipes it into the vehicle cabin, while a coolant heater heats up coolant which goes to the heater core where a fan blows air over the core and into the vehicle cabin. A coolant heater would allow you to also preheat your Volt’s ICE on a very cold day. With an air cooler you would need an electric block heater to preheat your Volt’s ICE.

Recently, Espar started selling a compact gasoline air heater called the B1LC which is an ideal heating solution for BEVs and EREVs.

Espar also sells gasoline coolant heaters and larger gasoline air heaters. The following link is Espar’s 2013 catalog. Gasoline models start with “B” prefix, while diesel models begin with a “D” prefix. (B1LC is on page 10).

The volt will fire the engine to get waste heat to both heat the cabin and warm the battery in very cold weather. No other external heater is necessary, because range issues are not a problem with the volt. Sure the battery range drops in cold weather, but there is the engine to produce power, and heat for when the battery runs out. Normally when plugged in the volt will keep the engine and battery preheated. The heat comes on instantly when the car is turned on. In very cold weather -4C and below the gas engine will start if the car hasn’t been plugged in for several hours. This will preheat the battery, and extend it’s range, and the waste heat will heat the cabin. One thing I have noticed is that the waste heat always circulates into the cabin. Even on a scorching hot day, if I run the battery out, and the engine starts, the vents start pumping out hot air for a few seconds, and then the heat pump kicks in and the air gets cool again, that is unless it is set to fan only. Then the air gets very warm, almost like the cabin… Read more »

Back in the day, a buddy of mine had a new ’72 VW bus that had a gas heater in it that ran off the gas in the tank. I always wondered why that was the only vehicle I ever saw that had one, as it was such a great idea.

The 1960 Corvair my family had used a very powerful gasoline heater. Then when Dodge claimed this was inefficient compared to their compact car, later Corvairs reverted to recovering engine heat.

The VW was that way because it was an air cooled engine. No liquid coolant means it didn’t have any hot coolant to run through a heater core to produce heat.

Other VW’s used a heater system that scavenged heat off of the exhaust. It circulated air around the outside of the the exhaust pipes, and blew that air into the cabin. It was a lousy system, especially once things started getting rust holes.

Using the scavenged heat off of a typical gas engine is still more efficient than a gas powered heater, because the heat in the coolant is waste heat that would just have to be released anyways outside the cabin. So it makes sense to use that heat to heat the cabin if it is otherwise just going to go to waste.

Compleeeetttttly negates the purpose of driving an EV. My Leaf is fairly unaffected by running the heater or the AC with the standard heat pump. I know this because I have run the air conditioner while the car is stopped and parked for an hour. The range indication barely budges.

For those of us with 2011 and 2012 Leafs, it makes a huge difference! May be worth considering as an aftermarket add-on, as we cannot get your heat pump. My heater uses 4.5-6.0 kW at full blow.

Yea, I have heard that. The heat pump really made a difference. If I ever go all solar I am getting one of those to replace my gas heater.

sorry but this type of heating in EVs was outlawed years ago on as Statik wellknows.

I think little propane tanks would be better.

BEV owners might be surprised how empathetic Volt owners are to this solution. Range budgeting a PHEV, as much as I like Hold mode, is a constant source of extra input for anything over 25 miles in weather, like today’s 10 degree Boston temps. Yes, we have a “net” with the 1.4ltr. It doesn’t mean constantly experiencing the inefficiency of a warm up cycle isn’t something many of us make great compromises to avoid, including “popsicle man”.

You heat your homes with gas and oil? No wonder you’re so fossil fuel addicted…

The noise of this heater is too great, it is recommended to consider the VVKB parking heater.
It is fully compliant with North American and European standards.
The spiral exhaust pipe can greatly reduce the noise.

What does PTC mean?