Just a thought. newbie here. (a kiwi living in Colombia with high petrol prices
If the question is demand:output ratio -------- why not tap into your alternator instead of your battery? (might need to add electronics so don't suck off too much juice) but wouldn't that bypass needing a relay switch/on-off switch for power up? Also the alternator at the higher revs would have increased output * increasing watts thru your cell?
let me know if you think this idea is viable! thanks