Would You Electrify Your Compact Sports Car?

In reply to Keith Tanner :

I've never said that motors put out more heat than engines do. Giving examples of that is pointless, Robbie asked me a legit question, and I answered. Electric motors do need a way to remove heat. Neither of us were asking you how much.

I also know that oil does not magically appear in tanks, and personally don't know any one that implies it does. I do know people that know so little about electricity, that it is akin to believing it just magically comes out of the wall.

I also remembering asking about transmission losses, and you answered with a number that was AMAZINGLY lower than my theory classes on resistance would have me believe. I also remember when I asked a polite and reasonable question for a deeper explanation, you declined to respond. I't has probably been covered somewhere on the forums I have not read, but I know that once, you just dropped out.

I do not mind learning new things. If motors actually are 80 -90 % efecient, it would be amazing, But I need farther proof that Robbie is not remembering that incorrectly. I remember it being much lower than that, You will note, no engines in my question at all.

Keith Tanner said:

It's quite clear that the amount of waste heat from an EV drivetrain is dramatically lower than that of an ICE. The heater in an ICE is driven by waste heat from the engine and it's a lot of BTUs. The EV needs heaters for the batteries, never mind the cabin.

I was amused to learn that for some EVs you get more range in cold weather by romping on the car at the beginning, because the higher discharge rate warms the batteries up enough that they become more efficient. :) 

BTW, The extra info in you post did not come through till after I replied. Thank you for the chart. I will have to look a bit closer at it.

And where is the 95% losses figure from. I am curious how they over come the resistance in the lines. Copper only achieves those kind of numbers in a lab, being supercooled down close to 0 deg Kelvin. And copper has way less resistance that what is used.

No, I would not convert an existing ICE car to function with electric power. I think there are too many compromises here.

I would, however, consider build a one off to run in that way. If you plan accordingly, picking your batteries and power output you could get the power right with the weight as light as possible. Could be a fun vehicle for autocross and time-attack.

Here's the source for that quote: https://www.eia.gov/tools/faqs/faq.php?id=105&t=3

If I dropped out of a discussion before, I apologize. Occasionally I lose track of them all or have to deal with other stuff. 

In reply to Keith Tanner :

Thanks for the link. My tiny head tried to explode trying to figure out how to get a percentage, but after 9 hrs on nights, that no surprise.

Their directions did not tell me much, either. If you could explain where you went, I would appreciate it.

What I did cobble together came out at around 62%, but I would suspect those numbers also, due to losses from resistance. Following Ohm's Law, it decreases the resistance (thereby helping to reduce the losses) at the higher voltages that they transmit at. But I'd need to see some more math.

As I said, my schooling was many years ago, and my best reference passed away a couple years (my Dad electrical Instructor - was known at N.N. Shipyard for solving  problems in the early 60's the E.E's couldnt. And that came from the E.E.'s)

I hope me asking questions about electrical theory does not take a thread about would you "convert to electric" too far out of topic.

Would I convert an ICE sports car that I liked to electric? No. Like you all mentioned, the cost and weight are turn offs and I enjoy the tingly sensations I get from gears and pistons. I realize those problems can be overcome, but I don't want a mortgage or to die in an electrical fire.

Would I convert an ICE car that I liked to run on bio-fuel? Absolutley. I plan to do exactly this to my next project for reasons of lower combustion temperatures and less toxicity. 

Would I convert an ICE commuter/luxury car that I liked to electric? Absolutely. There are a bunch of electric Kia Bongos running around my neighborhood. They are delightfully cheap, delightfully disposable after a few years and they have these delightfully goofy battery "saddles" hanging off the sides of the chassis under the bed. That they delightfully bolt up straight to a version of the normal Bongo transmission makes me think it'd be awfully cool to simply unbolt all that stuff as a sealed unit and then bolt it into a 1985 Dodge Diplomat or something like that. After all, the point of those cars is being slow and boring and comfy and quiet. That is, the exact opposite of what a sports car is for.

DaewooOfDeath said:

Would I convert an ICE car that I liked to run on bio-fuel? Absolutley. I plan to do exactly this to my next project for reasons of lower combustion temperatures and less toxicity. 
 

So you know, many bio fuels act almost exactly the same as the original fuel does.  And on the TP, post catalyst the differences are even less.  Oh, and the harmful chemicals they make are worse in some aspects.  But that's for a totally different thread. 

03Panther said:

In reply to Keith Tanner :

Thanks for the link. My tiny head tried to explode trying to figure out how to get a percentage, but after 9 hrs on nights, that no surprise.

Their directions did not tell me much, either. If you could explain where you went, I would appreciate it.

What I did cobble together came out at around 62%, but I would suspect those numbers also, due to losses from resistance. Following Ohm's Law, it decreases the resistance (thereby helping to reduce the losses) at the higher voltages that they transmit at. But I'd need to see some more math.

As I said, my schooling was many years ago, and my best reference passed away a couple years (my Dad electrical Instructor - was known at N.N. Shipyard for solving  problems in the early 60's the E.E's couldnt. And that came from the E.E.'s)

I don't have the background to math it out, I went straight for their own summary. I don't know what role substations have, for example. Someone else will have to explain how the rating was calculated. I assume there's been a lot of concerted effort in improving the efficiency of the grid because it has to be less expensive than new power plants!

I'd be more inclined to convert a car that I didn't like to electric. Would I love an EV Miata? Probably, but not that much more than an ICE version. Whereas there's something kinda cool about taking, say a 70s Ford Maverick and turning it into a far better car than it'd ever been. 

So much of the question boils down to what your aims are for the build. If you want Tesla power and range, be prepared to shell out some serious shekels. If you want something to plunk around town with, not so much. I'm kinda interested in ghetoceting a Leaf. I can get a used one with lousy range for $4k and up. My main concern is that in doing so, I'll upset the Canbus. Would like to hear feedback on that. 

So, that Tesla drivetrain posted upthread.  Does its orientation matter?  (Is everything splash-lubricated, or does it have an internal pump?)

Because I realized that if the motor were oriented behind the axle instead of in front, it would fit inside an existing trailing arm suspension.

Pete. (l33t FS) said:

So, that Tesla drivetrain posted upthread.  Does its orientation matter?  (Is everything splash-lubricated, or does it have an internal pump?)

 

Because I realized that if the motor were oriented behind the axle instead of in front, it would fit inside an existing trailing arm suspension.

That Model S unit in the previous picture is unfortunately splash lubricated so you'd have to figure out an external pump for gearbox lubrication. But I believe the newer 3/Y units have a pump so you could flip it backwards - I don't know about upside down. Fun thing about electric motors is that they really don't care which way they're spinning, so you could just run in reverse.

The 3/Y power units are smaller overall and clearly more evolved, but AFAIK there aren't any controllers yet. I hope I'm wrong about that.

{Late to the thread...}

I totally think there's a valid use case for electrifying cars when:

• Low production volume makes replacement parts nearly unobtainable
• Stock engines offer little performance and there aren't easy engine swap options
• Original drivetrains are stupidly complex, fiddly, or hard to keep running right
• EV conversion kits become more standardized, easier to obtain and less expensive

If/When conversions become affordable as any other engine swap it'll give a new lease of life to vehicles legislated off the roads for emissions. Not just post-1975 cars in CA, quite a few cities overseas ban old vehicles in their centers.

Hi Steve! I own an MR2 also and that thought has also crossed my mind a lot.

I can toss you more material to read up than you'd honestly know what to deal with- EV potential is staggering- but unless you've found some pretty mad Brushless DC motor (EV Smart Zytek motor?) or you've found a real monster of a Brushed forklift motor for drag racing i'd go AC and leave DC in the dirt. It's nothing against DC- the simplicity can be awesome- but AC intrinsically is more efficient and can do regenerative breaking without some of the wacky measures DC has to pull. As for using a Model 3's batteries- they're not much taller than the gas tank, so honestly I'd be more concerned about the front striking the steering shaft or pushing too far back into the engine bay. There was also a strut in the rear to add more support where the floor pan merges into the engine bay that you'd have to cut out and work around- I remember it VERY well when I redid my entire fuel system.

That Tesla3 drivetrain is interesting, and would easily plop into the back of an AW11.

It'll happen soon, but not yet. The Model 3's motor is Synchronous-Reluctance AC instead of the S/X which is Internal Permanent Magnet; SynR has a computer that switches on/off electromagnets in tune with the motor instead of using rare-earths that are constantly "on" to be far cheaper and be much more efficient. The tradeoff is they need powerful computers to control them, and so far we don't have a controller yet. The GOOD news however, is the Leaf's AC motor is capable of 300HP natively, is well packaged with it's inverter (so making a cooling circuit is easy)  and are very cheap. 

As for putting an Electric into a classic car? Definitely, it just depends entirely on what it is and why. For some it's an interesting idea to get a chassis back onto the road- for others, it's because their parts scarcity is so bad it's legit one of the only ways to keep it on the road (See the EV Ferrari 308 story; that happened because it's 3 motors and custom adapter plate to the transaxle was comparable in cost to a new engine). It also really is just what "complements" the vehicle more.

Also, there's reasons to keep the (Manual) transmissions. Hard to do any kind of regen on a box that isn't straight-cut gears, but torque multiplication is a thing and DC motors have a 'range' they like to be at where they're the most efficient. There's a few DC Motor swapped muscle cars I can post that use the 2-speed lenco box that is pneumatically-driven to keep torque in the 600lb/ft range. 

In reply to 03Panther :

All electric motors are extremely inefficient at turning electricity into movement.

(This has since been answered, sorry-GQ) If a motor is rated for 90% efficiency that means 90% of all energy that enters it is converted from electrical energy to mechanical energy, compared to even the best gas motors barely breaking 40%. Now, if you got into the nitty-gritty of TYPES of motors, there are plenty you'd never want in a car but not exactly for those reasons.

The Model 3's Motor is somewhere in the 92-95% efficiency range, but they are ballpark estimates based on what we can back-engineer and from outside experts like Sandy Munroe. Of course, that efficiency is it spinning in a bench; I think the total car's efficiency (energy to get it down the road) is something above 80% still.

I’m not actually asking folks to tell me that if a motor is rated at 90% efficiency, that 90% of the electricity is going to mechanical energy. I do know how ratings work. To be accurate, I don’t know what a gas motor is. A internal combustion engine, if burning propane gas, or gasoline or diesel, if it’s 40%, is not actually turning 40% of electricity it mechanical; needs more math than I can do to be a even comparison. 

What I am actually asking is an explaination of how numbers could be that high, without defying the laws of physics. My study’s were years ago, so things have improved some... I just have trouble believing it could be that much. “Because it is” isn’t really answering my question. 

KT linked to a site that shows only 5% loss in transmission lines, but their own data disagrees with that... telling me they are just telling people what that want to hear. 

Ive never heard of sandy Monroe, might be a household name in some circles, but I’ll have to look into that when I have a bit more time

as I’ve said, not bashing.. I’ve wanted an electric car since the 70’s. 

It's only defying the laws of physics if efficiency is over 100%.

Internal combustion engines generate a lot of heat as a byproduct of combustion.  Also a lot of pressure that gets wasted.   Turbo-compound engines use the exhaust to drive a turbine that is geared to the crankshaft and can get ridiculous levels of efficiency by recouping some of the pressure and heat normally thrown away, and increased engine operating temperatures reduce the amount of combustion heat lost to the cooling system, but there's still a good amount of heat loss involved and lots and lots of friction.

Somewhere I read that 1% of the world's energy production total was lost to piston ring friction.   That includes turbine engines, thermonuclear power, solar, hydroelectric...

Electric motors have none of those issues, and it sounds like the newer motors are not even using permanent magnets, which reduces the amount of "negative work" being done inside the motor.

Sandy Munro has done some high profile complete teardowns and analysis of a number of cars, most publicly Teslas.

Personally no. Not because I have anything against electric cars. But I suck at doing simple electrical things, So the thought of doing a whole bunch of high voltage electrical things with my skill (or lack thereof) does not sound appealing, nor particularly safe. Lol. 

I will probably buy an electric car at some point has a daily driver but I will probably continue to stick to cars made in the 70s and 80s as project cars that are within my skill set to restore and build.

Pete. (l33t FS) said:

It's only defying the laws of physics if efficiency is over 100%.

A heat engine has a theoretical limit (carnot engine) quite a bit less than 100%.  It's been a while since I took thermodynamics, but I'm pretty sure 95% isn't even theoretically possible for a heat engine.  95% *IS* possible for power transmission & distribution because that isn't a heat engine, it's just electrical conduction through a bunch of wires and transformers.

If the power plant that produces the electricity is a heat engine (coal, gas, diesel, nuclear) then it'll be subject to that carnot cycle limit, but generation is not part of "transmission".  Also, generally speaking power plants have much better thermodynamic efficiencies than the engines in cars.

the 200 HP WestEV conversion would bolt right up to my Porsche transaxle in my mid-engine Outlaw Bug.

The current ICE in the bug puts out 192.   And a flat pack of batteries would fit under the seat area without raising my shoulders above the window sills.  The engine compartment is plenty big.  And I'm using $10 gallon race fuel to drive it on Sundays... but, The price to convert is outside my budget.  Still... i think it is the future.

Maybe the next owner of the beast will make the switch.  

Don't forget that the efficiency question is really for the entire package. The motor may be 90%, but there's going to  be a lot of heat from the controller as well, and a little from the wiring.

My hangup, besides end-game cost, is the worry about adapting OEM controllers into cars they were never intended for. There's a famous-but-now-old story of someone buying a crashed Model S with the intent of fixing it. He did, and it wouldn't start—because since the car had been legally "totaled", Tesla remotely bricked it. I know he tried suing the auction place, but I doubt that ended well for him.

I can see Tesla's side of this: imagine the negative publicity of one of their totaled car being repaired by "a guy", only to end up bursting into flames on the street. On the other side of this, it means we're at serious risk of buying a $12K Model Whatever drivetrain and batteries used, having no idea what happened to the car, and potentially not being able to actually, you know, use it.

Unless Tesla relents (unlikely, what's in it for them?), it means waiting until someone builds an aftermarket controller intented for Tesla parts. It'll happen, but it also means more $$$$.

There are aftermarket controllers for the Model S motors, but not the 3/Y as noted earlier.