Hi, I am Chris and reasonably new to the world of PV for home use.

 

Over most of the last decade we have gradually reduced our dependence on Escom.  These small steps included:

- 12V lighting system, charged from PV.  7 years later we are still enjoying this installation.

- Next was the Geyserwise dual element PV installation.

- Finally convinced the lady of the house, and went with a gas stove-top.

- We opted for a Victron Multiplus (12/500) unit paired with a 100A.h battery for loadshedding purposes, wifi, computer, working from home, etc.  NOT linked to PV.

- 2015 we installed a Grundfoss poolpump, running of either PV or Escom.  The concept seems fine, but the pump only lasted 6 years.  A very basic mechanical failure destroyed the pump .... which leads me here.

 

Living in Cape Town we have opted for the various "off the grid" type solutions, to date.  Also, the power consumption of two people hardly justified the costs of a "full pv", at the prices of a few years back.

 

I now need to replace the pool pump.  The costs of another PV pool pump, given the mechanical failure we just suffered is having us evaluate various other options.

 

The costs of the current crop of PV type pool pump systems are such that I am looking at:

1.  A small pv installation for the home.  Having the geyser, stove and lights already off grid means our electrical account is low, and potential savings limited.  Adding the shlep of a split DB, etc. we are not keen on this route

2. Using the "pool pump circuit" to feed a 3kVA UPS. 

 

Our thoughts on the UPS -

- The UPS to plug into a "wall socket", thus removable and not part of the permanent electrical installation.  (NO feedback of power to the grid !!)

- The UPS to have a PV input, using maximum available sun and topping up from eskom as needed (not switch-over).

- The UPS output to have three plug circuits.  One circuit to feed the 500W pool pump, another to feed the 300 to 500W media, wifi and computer set.  The third line could be used for the freezer, also about 300 W.

- None of these needs additional run time during load shedding, so minimal battery power would be okay.

- The important bit is that the unit must use maximum available power from the sun, and only top up with eskom.  I am fine with the electronics and freezer running off eskom at night.

- I already have 5 off 100W 36V pv panels on the roof from from the Grundfos system.  These could be expanded as funds are available.  

 

 

Few questions:

- Is this even legal ?  Would I have to register it ?  I am hoping this could be seen as "off-grid".

- Is there an off the shelf unit that would meet these requirements ?  Or would it be custom combination of components ?

- Probably the most important question.  What other options are out there that I should be looking at ?

 

PS - if there are already threads covering this, would you kindly provide a link to these.

 

Thank you

 

Forgot to add - I did search for "UPS", but did not find any threads.

 

Maybe I should be searching under some other terminology.

 

Your guidance and assistance to this rookie will be greatly appreciated.