Quote:
Originally Posted by MetroMPG
Goodness! That means when my alternator is disconnected (running at 12v) my engine is making minus 100 horsepower!! 
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Here's one reason I would go with a hybrid type "boost pack" vs. an alternator delete (and I have a fair amount of experience running without an alternator).
In a word, "range anxiety". (Thank you GM)
Yes, you could always hook up your alternator again if you realize you're not going to make it to your destination before the 12v juice runs out.
HOWEVER, if you ever partially deplete your battery and then turn the alternator back on, you will take a massive fuel economy hit with the alternator running at high field current straining valiantly to bring the battery back up to ~14 volts again. Ask me how I know this.
Depending on how badly you misjudged your "range", your fuel economy could even be worse than if you'd just left the alternator connected from the beginning.
I dream of a lightweight, intelligent, portable lithium ion "boost pack" system that retains the ~14v level in the starting battery while the alternator is disconnected:
- the boost pack chemistry is better suited to deep discharges than lead acid (lower battery cost/cycle if done right)
- it has the advantage of being lighter than auxiliary lead acid batteries
- it's portable - could use it to power other 12v stuff sometimes
- it's portable - bring it inside to recharge instead of running a cord to your car, if not using PV solar panels on the car to recharge
- if/when you run out of range, you simply turn on the alternator to re-supply power; no massive "recharge" MPG hit since your battery was kept up by the boost pack
Just thinking out loud. |
What about design the battery so it can also be used in a hybrid bicycle? If the bicycle is then put on a stand, it should be possible to generate about 100-300Wh of free electricity every day. (And during the winter, even more savings by not having to run the heater as much!)
And in the car, design it to use regenerative braking. More free (recovered) energy.