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There is some useful information in the Practical Action Technical Brief Solar Voltaic Waterpumping
https://practicalaction.org/solar-photovoltaic-waterpumping-1 which also links to a good manual by Green Empowerment https://www.greenempowerment.org/images/stories/ge-sps%20manual_jan2007.pdf especially useful is the section on sizing your solar pump….
Sizing solar pumps
The hydraulic energy required (kWh/day)
= volume required (m³/day) x head (m) x water density x gravity / (3.6 x 106) = 0.002725 x volume (m³/day) x head (m)
The solar array power required (kWp) =
Hydraulic energy required (kWh/day)/ Av. daily solar irradiation (kWh/m²/day x F x E)
where F = array mismatch factor = 0.80 on average (a safety factor for real panel performance in hot sun and after 10-20 years) and E = daily subsystem efficiency = 0.25 - 0.40 typically
Therefore
The volume required needs to be in cubic metres per day rather than per hour as the rate of pumping will vary over the day. Let’s say 5m3 just as an example.
0.002725 x 5 (m³/day) x 20 (m) = 0.2725 kWh/day
Av. daily solar irradiation (kWh/m²/day x F x E)
The total solar irradiation received in a day can vary from 0.5kWh/m2/day in the UK winter to 5kWh/m2 in the UK summer and can be as high as 7kWh/m2/day in desert regions of the world, such as regions of Nigeria (Solar Water Heating in Nigeria, 2006) and the Sahara in Algeria. (Survey of Energy Resources, 2010) Many tropical regions do not have large seasonal variations and receive an average 6kWh/m2/day throughout the year.
Therefore we could use 6kWh/m2/day as an example
6x0.80 x 0.4
The solar array power required (kWp) = 0.2725 / 1.92 = 0.142 kWp which then needs to be match to the solar panels available.