I hate to burst your bubble but that's a pretty high expectation for a micro-hydro system.
- kw comes out to about 16 Hp.
- lb 1 foot drop = 1hp
water 8.345lb/gal
- gal = 8345lb
- / 8345 = 3.95ft drop per Hp X 16 hp = 63 foot drop
As you can see even if you could harvest every available watt in the stream and had no inefficiencies you would need a tremendous drop to get the power you want.
Just had a thought.
It wouldn't be practical for your application but would be fun to try. Rather than try to produce the power as you need it, produce power over time to use all at once.
Battery storage would be completely out of the question, I imagine you need quite a few hours of heat to get the job done, but if you used the electricity from the stream to produce hydrogen from water, and stored it up, you could burn it for heat. For instance say you could harvest the power of 1/4 of the stream and had a drop of 10 feet 33000/10/(250gal*8.345lb/gal)1180 watts * 70%(efficiency estimate)
826 watts. So for every 15 hours of hydrogen production you would get one hour of heat. 8 days would give you 12 hours. It might also give you a reenactment of the Hindenburg
Note: Due to ignorance I have not included the efficiency losses involved in producing hydrogen from water.
Hope you aren't too disappointed
Robert G