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Your instinct about this defying the laws of physics is a good one. As has been pointed out above, raising the water out of the well will "cost" you more energy than you'll get by dropping it back down the 250m you raised it, so the bottom of your well would need to be considerably higher than the turbine inlet.

I found your refugee camp and the hill I think you are referring to. It's about 300m higher than the camp, which means the bottom of your well is 50m above the camp - that's your "net" head. It will cost you 3.2MW to raise 1m3 / second out of that well, and you'll get 2.2MW back from dropping it 300m to the camp, so you've discovered a way to burn about 1MW of energy (rather than produce it). Those are the laws of physics you're (correctly) referring to.

A rather more significant question is "how much water do you think you'd get at the bottom of that well ?" To generate 1 MW from the top of the hill, you need about 500 litres / second, which is 43 Megalitres / day, which is enough water to supply a city of 300,000 people (Canberra, say,assuming 140 litre pcc). I very much doubt your hill has anything like that contained within it.

Solar panels are going to be your answer. If you think maintaining a solar panel is hard, try a 3MW Pelton turbine. Or perhaps, just hire an engineer to work on your scheme for you. Solar panels are far more cost effective than diesel so they'll pay for themselves quickly.

Best of luck,