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Kelmark GT Solar Series Hybrid

26K views 69 replies 16 participants last post by  Kernel Panic 
#1 · (Edited)
I have been in and out of this forum for about 3 months researching and I thought it was about time that I started my own build thread. Bear with me as this build will be slow. I am a 30 year old mechanic for a pharmaceutical industry also a Navy Reservist. I am a believer in sustainability and using resources efficiently and responsibly. I was a Diesel Mechanic for the Navy Active Duty for 6+ years and modified cars as a teenager.





The project is to make the most efficient car with respectable performance, range, and looks. To do this weight is my enemy. I found a light sporty car now I’ll need to trim the fat even more. This project will not be done until 2013 for many reasons. It is a project, a have a family, and I have a job so balanceing time is important. Also the availability of the 144V AC controller and the price of the batteries push the date out to then.
  • My skill level with auto mechanics and fabrication is above average.
  • The range (75-85miles at 70mph 75%DOD hybrid) (50-60miles at 70mph 75%DOD EV)
  • The level of performance you are hoping to get is <15s 0-60
  • Budget $25,000 + tax breaks + sponsors + friends
The Donor Car

Kelmark GT fiberglass kit car on a 78 VW chassis (Ferrari Dino Replica) This car will be built for local car shows and car audio shows.

I was unable to get the exact curb weight before starting but a stock VW beetle weighs approx 1800lbs and this car is likely 300lbs less so my guess is 1500lbs starting weight. Goal Finished Curb Weight <1600lbs

Drag Coefficiant 0.34
Frontal Area 21.9 sq ft

I see that the stock curb weight of a Kelmark is 1700lbs according to the blueprint. My revised finished weight is to stay at around 1700 lbs which means I need to find additional ways to reduce weight.

Modifications include

Stripped the chassis, replaced floor pans, welded a 3” body lift kit (to increase headroom and add strength to the pan), trimmed any excess metal, changed the head on chassis from ball joint to link pin, and lastly painted.

Purchased
ü Lightweight aluminum beam front beam assembly
ü 4 wheel disc brake kit (still need to machine to reduce weight)
ü All new suspension components
ü New performance transaxle (stock gearing)
ü Racing seats

Looking into;
o Lightweight Flywheel/ and HD Clutch
o Light weight rims and LRR tires
o Lightweight custom interior and stereo
o Reducing weight of fiberglass body
o Race windshield?

The Kit to be used

HPEV AC-50 (Hoping for a 144V controller by the time I am ready)

The Batteries

Dow Kokam SLPB 75106100 (QTY960)
7.5 AH 3.7V 15A Cont
Dimensions; .30 x 4.17 x 3.94 = .34 pounds
40 cells wired in series = 148V Nominal-166V Charged 7.5AH pack 15A cont. = 13.6 pounds
24 packs of 40 is 148V, 180AH, 360A cont 900A peak = 326 pounds

Instrumentation

The Display, stereo, GPS, Cameras, and security: MiMod- www.evinstuments.com


Series Hybrid

This will be a range extender or a way to charge when there is no access to a plug in. “Mainstream produces the world's lightest 2-kW diesel-powered electric generator. The generator is a completely integrated system optimized for size, weight, noise and reliability. This generator is not merely the coupling of a commercial off-the-shelf diesel engine and alternator.” Around 100 lbs and is more efficient and durable than gasoline generators.

Debating on whether to permanently install or have it removable when not needed.
http://www.mainstream-engr.com/products/engines/

Solar

I would like to be able to get a 3 mile per day charge from thin solar cells installed on top of the car. Still in planning phase, need to research more on how to install and which cells will give the best bang per buck. Also need to determine how much my car will use at 35mph for 3miles.
 
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G
#7 ·
While working with fiberglass boats I found that well built fiberglass bodies are not really much lighter than the steel bodies. Your ride will still be heavy unless you go with lithium but it will be a nice ride. If you can, put disc brakes on the front. It will help with the added weight. Upgrade the suspension. If you can get a narrowed beam for the front get a 2" narrowed beam and get a link pin style built for the later style pan. The link pin beam can handle more weight better than the ball joint and there is no real difference in ride quality. In my opinion the link pin is better for ride quality if the parts are new and adjusted properly.

Pete :)
 
#8 ·
While working with fiberglass boats I found that well built fiberglass bodies are not really much lighter than the steel bodies. Your ride will still be heavy unless you go with lithium but it will be a nice ride. If you can, put disc brakes on the front. It will help with the added weight. Upgrade the suspension. If you can get a narrowed beam for the front get a 2" narrowed beam and get a link pin style built for the later style pan. The link pin beam can handle more weight better than the ball joint and there is no real difference in ride quality. In my opinion the link pin is better for ride quality if the parts are new and adjusted properly.

Pete :)
You are correct in that it is not much lighter, to bad I don't have the money to thermoform the body then it would be. I am going to try to thin out some non-critical areas in the body in hopes of dropping 20lbs off the body. Also I am looking at lithium, very expensive ones...

Dow Kokam SLPB 75106100 (QTY960)
7.5 AH 3.7V 15A Cont
Dimensions; .30 x 4.17 x 3.94 = .34 pounds
40 cells wired in series = 148V Nominal-166V Charged 7.5AH pack 15A cont. = 13.6 pounds
24 packs of 40 is 148V, 180AH, 360A cont 900A peak = 326 pounds:D

I am also going to post some more pics of the car and some plans to trim weight later this weekend. Thanks for the sound advice.
 
G
#9 ·
Don't bother trying to lighten it only an extra 20 pounds. Keep the integrity intact and you will be a happy camper. My Ghia is an all steel body and I only run 96 volts and a 9" GE motor and it still jumps to freeway speed just fine. I have had it up to 85 mph already. Trimming the fat is almost not required with the VW because it is already trim and lean. What type of batteries are you thinking of using? AGM, Flooded LA, Lithium? I have 1024 pounds of batteries on board. Heavy but runs great. The 9" motor can handle that.

Pete :)
 
#10 ·
Here are my latest weight reduction figures. I don’t think I will be able to get below 1800lbs for a finished curb weight but we will see as things go. Still pretty light for an EV!
Approx Weight Breakdown:
o Gas tank removed w/12gal of fuel -90
o New Lightweight rims and tires -30
o Difference of ball-joint front end to new link-pin -35
o Difference of VW Engine and AC-50 Kit -26
o Race windshield -25
o Sand down fiberglass body -20
o Machine 4wheel disc brakes -12
o No Spare tire -10
o Lightweight Flywheel -8
o Exhaust -6
o Front Supports change from steel to aluminum -5
o Remove bumpers -4
o Add Battery Pack +326
o Add wires, charger, BMS, DC converter, brackets +50
I am not sure which engine was used in a stock Kelmark GT (assuming 160lbs)
· Great Plains VW 1600CC 55HP 160lbs
· Great Plains VW 2180CC 75HP 165lbs
· Great Plains VW 2600CC 96HP 190lbs
Here is a link to a brochure but I can’t read most of it and I could order one from another site for $70 for 6 pages not sure if it is worth it.
http://www.kdf-wagen.de/kdfwagen/a_show_page.php?iid=2230
 
G
#11 ·
There was no stock engine for the car. It was a kit so you could put in anything you wanted. Don't make the body skin any thinner. You want a good solid body and that 20 lbs will not make any difference unless you plan on doing nothing but racing your EV. For the street you will never notice that extra weight.

Pete :)
 
#12 ·
There was no stock engine for the car. It was a kit so you could put in anything you wanted. Don't make the body skin any thinner. You want a good solid body and that 20 lbs will not make any difference unless you plan on doing nothing but racing your EV. For the street you will never notice that extra weight.

Pete :)
I will try to avoid messing too much with the body. I was just going to have the body shop smooth out the bottom side of the body which is just rough uneven fiberglass. It might not amount to much but this car is going to be at car shows and want it to look clean.

Also the stock engine I was referring to was whatever is being portrayed in the blueprint when it says 1700 lb for the curb weight.

Jacob
 
#15 ·
I am looking for light affordable rims with a low offset. I found this one for $152ea. I know it is not a VW bolt pattern, I will modify this disc brakes to fit the smaller 4 bolt pattern. Here is a picture and some details.

If anyone knows of a better deal let me know so I can check it out.

Enkei RPF1 14x7 4x100 19mm Offset 54mm Bore Silver Wheel (8.6lbs!) The picture is of a larger 5 bolt.
 

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#16 ·
Solar

I would like to be able to get a 3 mile per day charge from thin solar cells installed on top of the car. Still in planning phase, need to research more on how to install and which cells will give the best bang per buck. Also need to determine how much my car will use at 35mph for 3miles.
Well this idea is probable not worth pursuing. One problem is your objective of Bang-for-the Buck. The least expensive $ for watt solar panels are thin film. However they are the least efficient of 10% or less. The most expensive (2 to 3 times more than thin film) are the most efficient of 17 to 19%.

Regardless of the efficiency, you can't really install enough panels oa EV to make much if any difference. I assume your electrical efficiency target is 400 wh/mile. IF you can achieve that, then that would mean the solar panel must generate 1200 wh to give you 3 miles of extra range.

I don't know where you live and thus your solar insolation measured in Sun Hour, but assuming your winter insolation is 3 hours means you need a 600 watt solar panel array. So here lies the problem, the physical area of a 600 watt solar panel is larger than the car.
 
#17 ·
Well this idea is probable not worth pursuing. One problem is your objective of Bang-for-the Buck. The least expensive $ for watt solar panels are thin film. However they are the least efficient of 10% or less. The most expensive (2 to 3 times more than thin film) are the most efficient of 17 to 19%.

Regardless of the efficiency, you can't really install enough panels oa EV to make much if any difference. I assume your electrical efficiency target is 400 wh/mile. IF you can achieve that, then that would mean the solar panel must generate 1200 wh to give you 3 miles of extra range.

I don't know where you live and thus your solar insolation measured in Sun Hour, but assuming your winter insolation is 3 hours means you need a 600 watt solar panel array. So here lies the problem, the physical area of a 600 watt solar panel is larger than the car.
I realize the solar is not going to contribute much; I hadn't gotten that far as to running the numbers. But it is more of an image thing... If I told you that I wanted to spend $1,000 for the cells and the clean, slick install what would you suggest using and how much power do you think I could generate. Here are some demensions and a car that had cells that is inspiring.
 

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#18 ·
Kelmark,

I don't want to rain on your parade, but the ideal wheels for an EV are going to be taller and narrrower. Something on the order of the original VW Bug 15x5" wheel with a 155 or 165 LRR tire is going to offer less rolling resistance and aero drag. There are numerous custom wheels available for the VW and 914 Porsche that would fit the bill.
 
#19 ·
Kelmark,

I don't want to rain on your parade, but the ideal wheels for an EV are going to be taller and narrrower. Something on the order of the original VW Bug 15x5" wheel with a 155 or 165 LRR tire is going to offer less rolling resistance and aero drag. There are numerous custom wheels available for the VW and 914 Porsche that would fit the bill.
Don't worry about the rain, in the Navy I learned to love the water...

Besides Bridgestone/Firestone B381 P185/70R14 has a rolling ressitance of .0062

And orginal vw rims are typical heavy steel rims unless you going to spend more money for alloy which are not common.

Also that narrow would be ugly on a Kelmark, the front tires on in the pictures are P215/60/R14.
 
#24 · (Edited)
should you go with solar cells on the car, you may want to look into these.
http://scientificsonline.com/product.asp_Q_pn_E_3026810
item 30268-12
assuming your voltage controller can handler higher input voltage to achieve the right charging voltage. you may want to use either 24 or 26 cells in series to get that high V-DC.
Price per 26 cells, $778, Based on a Constant Voltage charging system.

the other cell you might consider is this one.
http://scientificsonline.com/product.asp_Q_pn_E_3052286
as pointed out some are less efficient as this one is. using 14 of 3052288 will put your voltage above highest charging voltage to the controller.
Price for 14, $489, based around a Constant Voltage charging system.

one last solar sell i might suggest
http://www.goldmine-elec-products.com/prodinfo.asp?number=G15302
with these above at .45v take about 375 cells in series. if you have enough area on the car to place that many, it would be the best. though the cost will be higher then the other two i listed.
Price for this .45v cell at 375 cells, $1,875, not including shipping. no weight listed for each cell so no way to calculate weight added to the EV. could be either Constant voltage or constant current charging.

Since im not sure how the charging is going to happen. Is it going to be constant current or constant voltage charging? that might help in which cell to use. my suggestion of using a few more cells in series for higher voltage. Is due to what i have been looking into for solar chargers. that they can take a higher input voltage for the same charging voltage to the batteries. what this means to me by using more cells. Is that with what sun is out i can collect enough power to charge the batteries. If its kinda cloudy and im still getting some good sun it should be enough to charge the battier. same if the sun starts to go down. say the charger has 170-180 V-DC input voltage to charge at 166 V-DC. that gives you more time early morning or late evening to charge the batteries. Might be even enough to try to meet your 3 mile.

One other thing i thought of, if you can pull it off with out looking silly. implement a low starting speed windmill/turbine on the car. it would even be better since as the car is moving it would be charging at the same time. if the body was designed a bit differently you could have forced induction straight to said windmill/turbine in a hidden area under the body some where.

*edit*
im simply tossing ideas out there, how much will they work for this project i dont know. Though it does seem logical to me that using a wind type energy generation would be best for EV cars, that is built into the car it self.
 
#26 ·
should you go with solar cells on the car, you may want to look into these.
http://scientificsonline.com/product.asp_Q_pn_E_3026810
item 30268-12
assuming your voltage controller can handler higher input voltage to achieve the right charging voltage. you may want to use either 24 or 26 cells in series to get that high V-DC.
Price per 26 cells, $778, Based on a Constant Voltage charging system.

the other cell you might consider is this one.
http://scientificsonline.com/product.asp_Q_pn_E_3052286
as pointed out some are less efficient as this one is. using 14 of 3052288 will put your voltage above highest charging voltage to the controller.
Price for 14, $489, based around a Constant Voltage charging system.

one last solar sell i might suggest
http://www.goldmine-elec-products.com/prodinfo.asp?number=G15302
with these above at .45v take about 375 cells in series. if you have enough area on the car to place that many, it would be the best. though the cost will be higher then the other two i listed.
Price for this .45v cell at 375 cells, $1,875, not including shipping. no weight listed for each cell so no way to calculate weight added to the EV. could be either Constant voltage or constant current charging.

Since im not sure how the charging is going to happen. Is it going to be constant current or constant voltage charging? that might help in which cell to use. my suggestion of using a few more cells in series for higher voltage. Is due to what i have been looking into for solar chargers. that they can take a higher input voltage for the same charging voltage to the batteries. what this means to me by using more cells. Is that with what sun is out i can collect enough power to charge the batteries. If its kinda cloudy and im still getting some good sun it should be enough to charge the battier. same if the sun starts to go down. say the charger has 170-180 V-DC input voltage to charge at 166 V-DC. that gives you more time early morning or late evening to charge the batteries. Might be even enough to try to meet your 3 mile.

One other thing i thought of, if you can pull it off with out looking silly. implement a low starting speed windmill/turbine on the car. it would even be better since as the car is moving it would be charging at the same time. if the body was designed a bit differently you could have forced induction straight to said windmill/turbine in a hidden area under the body some where.

*edit*
im simply tossing ideas out there, how much will they work for this project i dont know. Though it does seem logical to me that using a wind type energy generation would be best for EV cars, that is built into the car it self.

Thank you for the links I will check them out. As for the windmill, I have seen many posts discrediting the idea, due to the drag added to the car uses more energy than you are gaining. But I have looked at some small turbines that could be set up on a pole when parked and charge your battery while away from home.
 
#29 ·
I forget exactly what I read, but it was either in Evo or Car magazine, saying that the new m5 will have some sort of micro turbines behind the grill that actually open up during deceleration to capture some energy.

or what about something like the Bugatti's air brake? but replacing it with turbines instead of a dam.



Neither idea would actually generate a substantial amount of power, but that doesn't take away from the cool factor ;)
 
#32 ·
hmm well using the wind turbine as a air break i dont think would work well. you would need in-efficient blade design for that to work. as in needing more wind speed to spin to generate power. my idea was to use this even at low speeds. this could also be a complimentary system to the battery system. In that you could use it real-time with batteries to use X current from the turbine thus saving power being used from the batteries. really the system im thinking of could be used in two different ways, would be ideal.

why do you say it wouldnt generate a substantial amount of power? just say you had the motor running at its most efficient, ie RPM/Voltage. lets say that its 80% efficient at that crusing speed, could be 55mph or 65mph. with the right gearing could even be at a lower speed as well. now with the right setup, the wind turbine might be more power efficient then solar. i really dont know any real numbers at efficiency of capturing energy from wind. Lets just say 50% is possible right now with current designs. even at some what low 50% efficiency it is much higher then the best solar. i guess the only different is that solar would be able to charge the batteries better over a longer period of time. though while in transit the wind would be able to generate more power for range extending. of course there is always a lose of power conversion, we just need to find that one that gives use the highest % efficiency.

i wish i new how to design cars, cause it really would be worth looking into IMO.

Evilsizer
I viewed the you tube, and I have thought of this as well. However fearing ridicule from other posters I haven’t said anything.
I have already incorporated it in my s-10. My thoughts were even if it didn’t work I would have reduced air drag.
I really didn’t know how well the “squirrel cage” fan would work and this video has offered encouragement.
I saved the alternator, and just experimenting wont cost much. At least I will know if it will work. I wont expect it to create much power, if it would equal the same amount as regen braking then it would be worth pursuing.
I’m NOT suggesting perpetual energy but just to get back what would be wasted on drag anyway. Take a look at my build thread of the airplenum on page 3. let me know what you think.
http://www.diyelectriccar.com/forums/showthread.php/1992-s-10-chevrolet-build-38834p3.html
If you find anyone else that has tried this let me know. Sorry for a long post
If i could do it and even if i was ridiculed for posting such a thing. i would ask how can you ridicule someone if you havent tried it to disprove it not being a good idea in the first place. seems that those that ridicule cant think out side the box. somethings thinking out side the box is got US where we are today in the world with the inventions we have. like this one invention i never knew about.
http://www.youtube.com/watch?v=e7nFga2BpGU&NR=1
after watching the video i had some ideas about home powering with it. air is around our house all the time, with the right system nearly free energy.

im really sorry for the rant, just thoughts i needed to get out. i should move some of this to a new thread.
 
#31 ·
Evilsizer
I viewed the you tube, and I have thought of this as well. However fearing ridicule from other posters I haven’t said anything.
I have already incorporated it in my s-10. My thoughts were even if it didn’t work I would have reduced air drag.
I really didn’t know how well the “squirrel cage” fan would work and this video has offered encouragement.
I saved the alternator, and just experimenting wont cost much. At least I will know if it will work. I wont expect it to create much power, if it would equal the same amount as regen braking then it would be worth pursuing.
I’m NOT suggesting perpetual energy but just to get back what would be wasted on drag anyway. Take a look at my build thread of the airplenum on page 3. let me know what you think.
http://www.diyelectriccar.com/forums/showthread.php/1992-s-10-chevrolet-build-38834p3.html
If you find anyone else that has tried this let me know. Sorry for a long post
 
#34 ·
I enjoy the ideas you guys have but I think the wind generator stuff should be on a new thread in like EV Performance were it can be discussed in detail without filling up my build thread. Great ideas though.
Kelmark
I apologize, I posted in the middle, and didn’t read the whole thread, You have some good points about the solar, and I agree the two ideas would be better in two separate threads.
 
#35 ·
Just got some real world data from Tom’s E-Swift project, he said 187WH per mile is what he is seeing at 35 MPH. This would equal 561WH total which would mean I would need a 280 watt solar cell. To meet my original goal, which is more cells than I can fit on my car unless I go with the really expensive stuff.
So I will likely be reduced to 2 miles per day or instead of charging the main pack I can use it on the aux battery saving power from the dc to dc converter. Still in the planning phase on this, lots of time to figure it out though.
 
#37 ·
Hi Kelmark

Why would tow gear add 50lbs?

When I had a road/track mini I had a square section tube welded to the frame, when I was towing I inserted a square section bar with a tow ball and held it with a pin

When not towing all that was visible was a square hole above the exhaust

Additional weight 3 lbs maybe 4

The electrical connection could be through a hatch - same one as usually used for charging?
This could do the trailer lights as well as the serious stuff!

A trailer tucked in close does not add a lot to your drag
 
#38 ·
Hi Kelmark

Why would tow gear add 50lbs?

When I had a road/track mini I had a square section tube welded to the frame, when I was towing I inserted a square section bar with a tow ball and held it with a pin

When not towing all that was visible was a square hole above the exhaust

Additional weight 3 lbs maybe 4

The electrical connection could be through a hatch - same one as usually used for charging?
This could do the trailer lights as well as the serious stuff!

A trailer tucked in close does not add a lot to your drag


It may be less than 50lbs so I am still considering this option. But on a vw chassis the frame or horns stop at the transmission I would either have to weld in pipe to extend that back past the motor to the back of the car which is to bars around 20" long then a cross bar.

With it extended out that far I would also need two diagonal braces 23" long and something to weld them to which run across the rear shock towers.

Another alternative is the prefab one that I will probably purchase; it is supposed to bolt to the bumper of a beetle. Because this is a kit car I would still need to do diagonal bracing to a bar mounted on the top of the rear shock towers to ensure that it is safe to pull a trailer.
http://www.hitchsource.com/volkswagen-beetle-or-superbeetle-trailer-hitch-68-79-class-p-27609.html
If do use a trailer I will increase the generator size from 2kw to 7kw and use a trailer similar to this one; http://www.bills-trailers.com/trailers/bushtec/roadstar.cfm
As for the drawbacks, you wont see allot of wind drag but the extra weight of the hitch and trailor is added to the generator for extra load on the car. Then you have two more tires and wheel bearings which add to the rolling resistance.
On the other hand 7kw would be much better at extending the range, 60 amps after power conversion losses could sustain speeds of 40mph as long as you have fuel and double the range of the pack at 65mph!
 
G
#39 ·
Just thought I'd post the trolls message so you know what it says.


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Wants to understand that many details please access our websites: www.yellowstonediesel.com

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#41 ·
why not come up with a wheel hub powered trailer. that way your not losing speed if you need faster then 45mph. if you do the generator it could directly power the wheels or you could use a small pack to power them or some mix of the two.
I am not sure what a wheelhub powered trailer is? Are you talking about a pusher trailer?

"On the other hand 7kw would be much better at extending the range, 60 amps after power conversion losses could sustain speeds of 40mph as long as you have fuel and double the range of the pack at 65mph!"

I wouldn't be losing speed with the generator trailer, I was just commenting that at around 40 mph the generator could maintain that speed without the assistance of the battery pack. When I go faster it will use the 60amps from the generator and the rest from the batteries so speed will not be limited.
 
#45 ·
Im with you Kelmark, I am not a fan of the trailer concept...I would much rather go with a removable spot inside the car where you could "install on demand".. I am planning the same sort of setup...

7.5kw should be enough to power a lighter weight good aero car continuously at 50mph...You can find gensets for 900$ that are about 230lbs for 10kw peak 7.5kw cont.
 
#46 ·
Im with you Kelmark, I am not a fan of the trailer concept...I would much rather go with a removable spot inside the car where you could "install on demand".. I am planning the same sort of setup...

7.5kw should be enough to power a lighter weight good aero car continuously at 50mph...You can find gensets for 900$ that are about 230lbs for 10kw peak 7.5kw cont.
If I have to take it in and out of the car I need to keep it under a hundred pounds so it can be lifted by just me. I found AVERO™ FLEX-LITE (FL) 2.5 kW AC/DC Diesel Powered Generator Set which is under 100lbs.

Another one I am very interested in is 5KW and weighs 165lbs;
http://www.centralmainediesel.com/stats/PRINTABLE/yanmar_4kw.asp?page=yanmar_4kw

Does anyone else know of any light weight diesel generator with auto start?
 
#48 ·
The problem w/ most gensets is that they're relatively heavy in order to lower costs. It's better to go w/ an integrated lightweight engine/exhaust/transmission that's more efficient and only ~100lbs heavier than a underpowered generator, bu as usual those are just my 2 cents.
 
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