Alternator delete with regen braking modification for better MPG

[Daox]

Tested it out on the way home today. Everything works perfectly.

[Daox]

Lets tidy things up and finish up phase one of this project.

First off, a little 3d printed goodie to make this mod nice and easy to undo. I printed a low profile fuse body, and made my own blades for it out of some old furnace ducting. Definitely not necessary, but cool and makes things a bit more polished.









Now, add in the blades. I soldered the wires to them first so I wouldn't melt the plastic. Then a couple dabs of super glue to hold it together.







Then, the rest of the circuit got wired up. The one odd connector / bent tab thing I pulled out of some old electronics component. It plugs into a slot in the fuse box that is a ground. I am still missing a fuse (since I removed the one in the fuse box). That'll be added a bit later. Not too concerned about it though.





And, here it is installed for the time being. Yeah, this means to switch on the alternator I have to pop the hood and open the fuse box and flip the switch. It'll be fine for now until the next phase.

[timw4mail]

So, with the deep-cycle battery, what kind of distance do you think you could go without recharging?

[MetroMPG]

Did you get to try "regen" as well on your drive? Can you feel the difference?

[Daox]

So, with the deep-cycle battery, what kind of distance do you think you could go without recharging?

Great question and the answer is highly variable. A group 24 battery like the one I have has roughly 85 amp hours of capacity. At 12.5V, that gives us 1063 watt hours. So, lets look at Darin's Metro load list to get an idea.

"60watts engine idling @ 880 RPM (alternator disconnected)"

So, just idling it would theoretically last 1063 / 60 = 17.7 hours.

Lets assume that idling and driving takes the same electrical power. But, now it starts raining. So, you turn on your headlights, wipers, and defroster fan.

"49watts heater fan 2
36watts wipers low
112watts headlights, dash lights high"


Holy cow we went from needing 60W to 257W! So, we do the math: 1063 / 257 = 4.1 hours.

That still sounds like tons of run time, right? It really is. However, there are several other things we want to keep in mind. First off, in order to maintain decent battery life, we don't want to discharge a lead acid battery beyond about half. Yep, half. So, we're down to 2 hours. Now, lets say it is winter. Lead acid batteries loose capacity in winter, most guys claim at least 30% (I would probably argue higher). Now we are down to 1.4 hours. Still a respectable about of time for a daily commute. However, in a few years the battery will loose capacity as it gets used. So, you need to kind of take that all into account as you size your battery. For my ~50 minutes of driving a day, it'll be just fine.

Did you get to try "regen" as well on your drive? Can you feel the difference?

I was not able to enable 'regen' mode yet. That is coming up as phase 2 of the project.

[MetroMPG]

You should mount a wind turbine on the roof to generate power while you drive!



And solar panels for when you're not moving.

[stevedmc]

You should mount a wind turbine on the roof to generate power while you drive!



And solar panels for when you're not moving.

Increasing wind resistance kind of defeats the purpose of this project.

[inuvik]

You should mount a wind turbine on the roof to generate power while you drive!



And solar panels for when you're not moving.

You could mount a small fan turbine in the lower grill to generate electricity as you drive. Even it only generated 140 watts that would be 10 amps of power @ 14 volts.

[Loren]

So, given your short commute, are you planning to just home-charge the battery? Sort of a "plug-in hybrid" electrical system?

[Daox]

So, given your short commute, are you planning to just home-charge the battery? Sort of a "plug-in hybrid" electrical system?

Yep, thats the idea.