Penny, a wild guess but I think Bobert's would need a huge investment in solar equipment.

Never tried a project like yours but I'd guess it rather more affordable even though it could still add up.

I'm not sure but one idea I might consider if trying something like that would be rather than have it pump all the time to have a top reservoir and pump up to that. I could control that via a solenoid valve and float switch.

Probably the first thing to do though and I'd have to do a lot of googling for this to find out how I think would be to get some idea of the flow rate (eg. litres per hour) in your stream. Then it would be a case of trying to find what pumps can deliver what you need and what power they consume.

I don't know for your project but for one I once had in mind before opting for pressurised watering was to lift the water a couple of meters to tank and gravity irrigate. For that, the best candidate pump I found was a marine bilge pump.


Anyway, cluelessly rambling here though trying to kick out a couple of thoughts...

It may be worth an Internet search to see if you can find anyone who has done similar.