CB59

That's quite interesting. It just feels like it should be more. But with what you're saying about being off grid and having to supplement, that helps in understanding my setup is not far off. Thanks for the calculations. That helps quite a bit to put things in perspective!

They are due north and installed on an ibr roof with a bracket to allow slanting. Geyser above the tubes with about 45⁰ pitch (my guess, not measured). I do not think I have a circulation pump (not sure how I would determine this). Units were around 800-900KWh during summer and currently about 1000KWh.

I'm posting because I could not find anything on Google or this forum. If I have missed it, please link it here. I have had a 15 tube evacuated 150L solar geyser setup installed that feeds my current geyser/heat pump set up. The idea is to save on heating cost and have enough water to supply the house. I've seen that my electricity bill never went down since the installation and I wanted to know what should I expect in terms of temperature gains from my solar geyser (with no electric heating element). My current daily gain is around 15⁰C, with about 8⁰C losses and 1 person showering another 7-10⁰C. This does not seem correct to me, even at this time of the year. Any advice?