Number of solar panels

[Jeppe]

I ordered a deye 5kw inverter and 2 x polon 5.1kw batteries. 

 

I need to get solar panels, question I have is my idle draw at home is about 400w. What is the purpose of having 10 panels making 5000w when most of the time it's just going to be wasted. Is it for the occasions where I use high wattage appliances?

[Eugenevz]

This question is two fold, first off most inverters have a minimum voltage requirement to actually start up, i think the one you mentioned has a 150V start up requirement. So you are going to require the minimum number of panels to achieve this.

Other important considerations to make is whether you want to off load some of your current usage onto the solar energy so that you can offset some of the cost via your electricity bill, will the solar panels produce enough energy for all situations to charge the batters ie cloudy days and so on, or are you simply content with charging the batteries from the grid.

Secondly tho and honestly this decision can only be made by you, do you want to simply "survive" loadshedding, do you want to become semi self sufficient, will your system cover worsening stages of loadshedding, do you aim to go off-the-grid on day, can you afford what ever setup you decide to go with ie don't go with short term loan/bond repayment, you'll end up paying back a multiplier of 2.5 times depending on interest rates and terms of the agreement.  

Finally also consider that there is cost associated with installing panels on a roof (unless you do it yourself), these costs are often so large that it rarely makes sense to get them installed if you go with a small number of panels