Objective:  Lift  5000 litres of water 10 - 15m.  CHEAPLY

 

Solar PV is good. . 12v dc Pumps are great for pumping a lot of water with low head.  A Seaflow 12v DC 2000 gph bilge pump is $35 on Amazon. They are often used for waterfalls - so they can handle continuous pumping, and have a built in float switch.  All  that is good but it is not going to go uphill!  Enter the idea of the cycling pivot beam. A re-think on the old Egyptian Shadoof.

 

The image shows the 2 extreme positions.

 

The BIG bucket (220 ltr) becomes the human repeatedly adding his weight to the short end of the shadoof.

 

First ... some detail.  The balance beam needs to be balanced.  The  long beam will require LOTS of fixed weight on the short end to ALMOST balance it. However  we still want the small bucket to be a little heavier.

 

The longer the beam the better -  guy wires acting like bridge suspension cables will help a lot. I'm shooting for a total length of 7m. 6.5 m on the long side of the pivot.

 

The higher the pivot the more total lift. Lift is generated both above and below the horizontal.  Getting the pivot point high means more construction.  I'm thinking 2 x A frames made of with vertical height of 4m.

 

The 2000 gal submersible pump sits in a cistern. It will fill the big bucket every 2 mins.  That is 600 ltr/h

 

The big bucket descends to the same level as the pump when full discharging its water into the pump cistern. Although the 20l bucket will rise 10m the BIG drum will only change height by about 80cm  The pump has no trouble with that.

 

I built a model. It has the small bucket 62cm from the  pivot with the big bucket 5.5cm on the other side.  2ltr will lift 222ml.  about 1m.  If we scale it up x10 .... That is very near our system sizes..  So max lift is 4m + 6m = 10m .... not too shabby!