BLM Announces First Cut on Oil Shale RD&D Proposals
Firefly Energy Awarded Patent on New Foam Lead-Acid Technology; Targeting Hybrids and Plug-ins

Startup Introduces 330MPG Diesel Hybrid Design

A rendering of the Aptera

Accelerated Composites, a San Diego, California-area startup, has designed a two-seat, three-wheel parallel hybrid—the Aptera—to achieve up to 330 MPG and sell for less than $20,000.

The Aptera hybrid is to be built from lightweight composites, and designed to deliver its 330 mpg in normal city and highway driving and demonstrate acceleration and handling similar to that of a Honda Insight.

Accelerated Composites claims that the coefficient of drag on the vehicle will be 0.055-0.06—an order of magnitude lower than any production vehicle on the road.

The production powertrain will consist of a 12 hp (9 kW) diesel engine with a 25 hp (19 kW) permanent magnet DC motor. (Accelerated Composites is designing the prototype with a gasoline engine for cost.) The electric motor is coupled through a Continuously Variable Transmission (CVT); when the engine is off the car can run on the electric motor alone.

The company plans to use ultracapacitors for energy storage, although it is working with lightweight lead gauze batteries in the prototype. (Lead gauze batteries suspend the electrolyte in a gauze material.)

The Aptera weighs 850 lbs and is made almost entirely of lightweight composites, based on Accelerated Composites’ Panelized Automated Composite Construction (PAC2) process. It accelerates from 0–60 mpg in 11 seconds, and has a top speed of 95 mph.

Depending upon the completion of funding, a prototype could be ready to roll as early as the end of March or April, according to Accelerated Composites founder and CEO, Steve Fambro.


Roger Arnold

The front wheels are too far forward! For stability in a trike, either the CG must be *very* low, or it must be near the axle for the paired wheels. Between them, the two front wheels should carry 70% of the vehicle's weight. From the drawing, I'd guess that they carry no more than 50%. That means the effective base width against roll-over will be 50% or less than the width of the front axle.

You could try to solve the stability problem by making it a leaning trike. But AFAIK, nobody's ever succeeded in building a heavy, motorized leaning trike. The only ones that have ever worked have relied on human muscles as actuators and human neurons as control system.

Also, it's going to be slow on long uphill climbs, if you have only a 12 hp motor and supercaps for energy storage. The supercaps will be drained in the first few hundred feet of elevation gain, and then you'll be left with what the 12 hp engine can supply. Better avoid Tehachapi!


As far as all the blather about big cars... remember as ofen as not big cars are a reaction to personal needs and driving routes that include 18 wheelers.

My sister a few years back got hit by an 18 wheeler and if not for her large car shed be dead right now.

Add to that the need to go on long 6-7 hour trips with comfort abd safety with 18 wheelers EVERYWHERE...

And mix in the final nail. Getting old both my sisters need extra room as they no longer bend all that well.

Oh and both these large cars get 32 plus miles per gallon.


Maybe 24 hp instead of 12 for the extra torque to go uphil as Roger mentions. Surely this would not drop the 330 mpg to 150, because the engine would be less strained, so maybe 250 mpg.


My Volkwagon Sirocco was totaled by a semi hauling scrap metal and I walked away without injury. Does my story cancel yours? Or is the Sirocco "big" in this context?

(The fact is that "safety" of big cars, particularly SUVs, is an example of "bounded rationality" in the buyer. Studies show them to be less safe, but people do not belive studies. They prefer to belive their less congnitive "bigger better" instincts.)


some data:


For every story that someone survived an accident in a big car, there are probably two stories of people that avoided the accidents in the first place by driving smaller, better handling cars. Of course there's no way to statistically prove this, but anyone who's driven both kinds of vehicles in heavy, fast moving traffic knows this to be true. On the other hand, if you're the kind of driver that knows you're going to be in a wreck no matter what kind of vehicle you drive, maybe barricading yourself inside a tank IS your best bet.

The kind of crashbox design talked about above sure works in race cars. You see them going end over end at over 100 mph and the drivers walk away. How many tumbling SUVs do drivers walk away from?


I cant wait. How many can they make a day :)
I need a new car next year and this looks good
if it has heat and air I am set..



Te concern that you need double the HP to make more torque isn't neccesarily true. For one we don't know how much torque it's making already :)

Diesels are very torquy in comparision to thier HP, because they often redline way before 5252 rpm... which is where the HP and TQ curves meet.

But with a weight of only 850Lbs; it doesn't need that much power even up hill. A horse weights more than that and only has 1 hp; and can easily go 35mph uphill ;)

People forget just how much power is represented by 1hp because they are used to 2000Lbs-3000Lbs+ vehicles. I don't imagine it'd be a big problem, especially having a CVT. Certainly no pike's peak car though :)

Good points re: Insurance; But even if the insurance is double what I pay on my Insight; it would still pay for it's self in gas savings.

I too would like to know some skidpad #s on this thing :)



330 mpg really isn't as good as you think.

look at it this way.
1 gallon of diesel will move the 850 lb vehicle 330 miles
330 miles * 850 lbs = 280500 lb*miles/gallon or
1/280500 gallons to move 1 lb one mile.
let's us the 1st number so I don't have to type fractions.

a semi truck can weigh up to 80,000 lbs and gets mpg in the 6 range though I have heard claims of up to 8.

80,000 lbs * 6 miles = 480000 or 1/480000 of a gallon to move 1 lb one mile

480000/280500 = 1.71 and change
The semi truck is 1.7 times more efficent than the car.

Suman M Subramanian

The motorcyclists reading this may be familiar with England's Norton and BSA, and the USA's Indian and Excelsior-Henderson. All of these companies produced desirable bikes at one time, but all went bankrupt. The two American marques were resurrected in recent years & actually sold a few new (but horrendously overpriced) bikes, but eventually both again went bankrupt (I suspect due to overly optimistic payment arrangements with their lenders), to the extreme chagrin of buyers who were then stuck without warranty or parts support.

Having a great product is one thing, having a good business plan is quite another (as every failed company found out the hard way). As long as a company can make enough profit to stay ahead of its debts, it'll stay in business. It's said that profit = margin x volume, and I hope it's the volume side of that equation that really takes off. I assume that means having a large & reliable dealer network, so average customers (beyond the avant-garde early adopters) can reasonably expect long-term parts & service support.

Will a motorcycle license be necessary to operate an Aptera, or will that only affect how much insurance will cost (i.e. lower insurance if you have rider training/license)? If it's required for operation, that could limit the potential customer base (think volume). Also, a friend of mine commented that the outward visibility might be poor with those wide pillars. From a weight standpoint, I don't know if more window area or a wide angle camera system is the better way to go (reliability would favor windows).

I hope I sound less like a pessimist & more like a realist, because I'd *really* like to see the Aptera & roomier versions succeed.


Ryan perhaps; but 1: this isn't a turbo diesel
2: Miles Per Gallon per Pound is an mostly worthless measrument.

It is akin to people with slow cars who claim that thier engine makes more HP/Liter when thier car is outrun... it's true, but no one cares, because it doesn't have any bearing on the fact that the car is slow.

Likewise, the diesel semi may get more miles/gal/lbs, but it still only gets 6mpg.

If you want miles/gal/lbs; look at the upcomming hybrids freight trains :)

Some Guy

Thank you Ryan for your analysis of miles/gal/lbs and making me even more optimistic about this product. If a semi truck can get that kind of efficiency, then I expect a 500 mpg Aptera soon. This simple calculation just grounds this amazing product in reality and means we have even more to look forward too. All we have to do is drop the weight, decrease the drag, and increase the efficiency of the engine. All these seem reasonable seeing as the technology is evidently already available. Now that this project is under way we should start demanding even more.

Jesse Jenkins

"330 mpg really isn't as good as you think."

Ryan, we're not comparing this car to a semi-truck, we're comparing it to other vehicles that transport one or two people around - i.e. most cars since they are driven with only one person in them nearly all the time.

Comparing miles/gal/lbs is not a very good measure of utility. Hauling around pounds of stuff may be what a truck is designed to do, but not a car. A car is designed to haul around people and it doesn't particularly matter much how much they weigh.

If you want to compare vehicles, compare their utility (i.e. what useful tasks do they perform) and how efficiently they perform those tasks: the Aptera is a two-person transporter. Compare it to, say the Honda Insight. They both can transport two people around but the Aptera can do it with a fraction (1/5th) of the fuel, i.e. it does its comparable task 5 times more efficiently!

Robert Burns

This is the best news I have encountered in a long time on breaking the stranglehold of expense, petroleum dependence, smog, and ugly automobiles in a long time. I see that a lot of safety consciousness has been incorporated into design; I hope that the instability issues of using 3 wheels, and the wheel-alignment and center-of-gravity issues addressed above, are conscientiously and thoroughly understood and adequately mitigated. Let's end the subsidies to S.U.V. for dangersousness, fuel inefficiency, and consumer ignorance for a brighter future for innovation. Please keep me posted.

Joseph Willemssen

"330 mpg really isn't as good as you think."

Right. It's "only" 6 times more efficient than the most efficient cars on the road today.

We better dismiss this inefficient technology.




LOL, it makes me happy.

The purpose of the example was to illustrate the difference between efficiency and economy.

“... All we have to do is drop the weight, decrease the drag, and increase the efficiency of the engine. ...”
Yep, it is not magic. The trick is doing all that while keeping cost in check and without sacrificing too much utility.


"...If you want to compare vehicles, compare their utility (i.e. what useful tasks do they perform) and how efficiently they perform those tasks ..."

Congratulations you hit the nail on the head

I am excited to see a diesel hybrid, because you can typically run a diesel engine at a higher compression ratio than a gasoline engine and hence more efficiently. I am also glad to see that they plan on using Ultracapacitors rather than NiMh batteries. Ultracapacitors can be changed /discharged faster, NiMh batteries have an expected life of 1000 charge cycles where as Ultracapacitors this is more like 10,000 to 1,000,000 cycles. I would not buy a hybrid with NiMh battery packs for that reason, I'll hold out for Ultracapacitors.

“...the Aptera can do it with a fraction (1/5th) of the fuel, i.e. it does its comparable task 5 times more efficiently!”

Fuel economy is not the same as efficiency.

5 times more economically yes and that is what people care about. (assuming that the price of diesel and unleaded are the same)

330 mpg would be nice but because 1) the aptera can't do what I need to do 2) At current fuel prices, if I used the aptera as a commuter vehicle the savings in fuel over my current vehicle would not offset the purchase price of the vehicle within the expected life of the aptera.
Therefore I will not buy one, until it is economically justifiable.

On the 3 wheeled design.
My school built a solar powered vehicle that was a 3 wheeled design with a wheel hub motor in the rear and 2 steered wheels up front like the aptera. Since it was to be driven on public roads for the race it had to be licensed all all that, it was registered as a “rebuilt motorcycle” because of the 3 wheeled design. Other states could have different regulations.

It is very easy to get angry and point blame at one group or another but ultimately this does nothing to improve the situation.

Engines have continued to improve in efficiency even though average fuel economy has been going down since 1988.

One improvement that I would like to see (it is in progress) is motor fuels with lower sulfur content, and or higher octane. A reduction in sulfur would reduce harmful emissions regardless of the vehicle.
Higher octane fuels permit you to run at a higher compression ratio (more efficient), and at a given compression ratio an engine running the otto cycle (4 stroke gasoline) is more efficient than the diesel cycle.
However current fuels and materials limit us and we can run a diesel engine at a higher compression ratio than a gasoline engine, hence we see higher efficiency in practice with diesels.

If you want to learn more about emissions, sulfur, and how air fuel ratios all play a part. This article from Toyota gives a good explanation.

Jon Rodman

Hello Everyone,
I like that concept. It sounds as if nearly all of the drivetrain parts are readily available. I would buy one.

Actually, it has me thinking that it may not be that difficult to build one at home in my garage.

I am going to look into the legalities of building a custom made three-wheel motorcycle and registration/inspection and insurance issues.

I hope they get some financing and actually produce some of those vehicles. I am sure they will sell all they can produce at that price.

I also have more confidence in the safety of a "Crash box" design than the traditional designs.

At 300 miles per gallon a 15 gallon tank of fuel will last 4500 miles. I would only be buying fuel once every three or four months. Imagine...

Jon Rodman

A previous post mentioned the license plate affecting the vehicle's aerodynamics.

An advantage of Motorcycle registration vs. automobile is the license plate requirement.

At least in New York, motorcycles are only required to have one license plate. The motorcycle plate is much smaller than a car license plate. In NY cars are required to have two relatively larger license plates. One on the front and one on the back.

Attaching one small motorcycle license plate and light to the back of the Aspire would not drastically affect the aerodynamics.



As for going 4500 miles between fuel up, it would be like the old days where you would check your oil at every fill up, except now you could change it at every fill up.



The website has little useful info on the technical aspects of the energy storage, drive train, etc. Until everything is layed out, this seems more like vaporware to me.


If motorcyles and trikes are legal, it would be something to see the car disallowed for any other reason than oil companies wanting it suppressed. I can't wait to test drive the Aptera!


What seems least believable to me is the press-release statement that they have figured out a way to make the lightweight composite body cheaper than anyone else. There is so much demand for inexpensive lightweight composites that I find it hard to believe that it would make sense to use their discovery in a new car instead of in something smaller like skiis or tennis rackets. As the press-release points out, composites are used more and more in aircraft design so there is huge demand there as well.

That means the company would have the opportunity to make huge profits licensing it's technology without all the expense of trying to develop an entirely new car.

Russell Phillips

I wouldn't get too excited. If you didn't notice days after Accelerated Composites announced plans to build this suddenly car safety is all over the news (I'm sure it's a coincidence). I'm betting you will soon see legislation setting new "safety" standards.

This 330mpg car might be safer then everything on the road now but I'll just about guarantee the legislation will be written in such a way that instead of having to meet certain standards it will insist on certain materials (for instance steel) be used, reclassify 3-wheeled vehicles, height restrictions, etc... basically whatever it will take to make this car illegal to build. Then once they go out of business then those rules will be changed back.

Watch for it. I hope I'm wrong but keep an eye on the news and see if something like that comes up. See if you can find out what they are proposing if they do. Or maybe just put a reminder in your calendar to do a search in 6 months about this company, "safety" legislation, etc...

Maybe I'm just feeling pessimistic today. 8-P


VW built a "one liter" diesel car (250+ mpg) a while back. Unlike the Aptera, the VW vehicle:

1. Actually existed
2. Was built by a real company
3. Had a suspension
4. Could be entered by adults

VW originally hoped to produce a series of cars based on this vehicle, but abandoned the effort after deciding they couldn't hit their $25k cost point. Although not a real hybrid (idle-stop only) the design featured expensive components such as a composite skin, magnesium space frame and seats and an automated direct-shift 6 speed gearbox.

I hope AC beats the odds and brings the Aptera to market. It'd be fun to have one. But it's not really practical. Even with today's "high" gas prices a typical US car driver spends $1200/year on fuel vs. $3000++ on insurance, maintenance, depreciation, etc. Few people with resources to buy a new car want to make major sacrifices to save less than $100/month. Now if gas was $10/gallon it'd be a whole 'nuther story.

The comments to this entry are closed.