Solar Scenarios for running the essentials (lights, computers. Internet, TV setup, fridge etc.) being fed by our Solar Panel / Inverter / Battery Installation. The non-essentials include the Geyser, Air Conditioner and Electric Stove and they remain tied to Eskom.

Basically an algorithm that attempts to:

1. Maximize the use of the panels
2. Minimize our Eskom bill

During the day:

1. Panels do have enough juice to run the essentials,
1. excess charges the battery


2. Panels don't have enough juice to run the essentials,
1. use Eskom if available, otherwise
2. use the battery

At night and until the next day arrives:

1. use the battery to run the essentials
2. if the battery does not last, use Eskom



Never use Eskom to charge the battery.

BUT!!!

Aaaaagh (***) - If the battery is not charged by 3 PM. then use Eskom to charge/top-up the battery.

As I was typing the previous paragraph, I thought could hear the smart inverter in the garage shouting,

"Sorry, I cannot do that!".

*** I gave the above, my Solar Panel / Inverter / Battery / Eskom / Hamster on a Tread Mill best practice scenario to Utility Africa. It was returned marked (as in school), together with some comments. There was actually only one comment, and that dealt with a strategy for making better use of the (charged) battery in order to further reduce our use of Eskom, decrease the monthly Eskom bill, and reduce the time taken to redeem the cost of the the installation.

Utility Africa's comment/suggestion was to use Eskom if it is available to charge the battery if needs be between 4 - 6 AM and again between 4 - 5:30 PM.

The inverter is smarter than we think it is.

### I did think of doing something similar, but was not familiar enough with the Inverter to come up with something that would fit. The reality is that Inverters are basically a computer system with a bunch of switches and wires either carrying current, or drawing current that can be connected by means of the switches. The program (algorithm) that does this does the real work, and I guess it is another feather in John von Neumann's cap for inventing the General Purpose Central Processing Unit (CPU).

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Some links

• Utility Africa - Our Solar Panel Contractor
• News24 MONEY CLINIC | What are the rules for installing solar power when living in a complex?
• Daily Maverick Article - Home power backup systems – electrical engineers answer your questions
• Daily Maverick Article - The energy transition - it’s not just about the technology - Chris Butters

Tribute

• John von Neumann - a Hungarian-American mathematician, physicist, computer scientist, engineer and polymath.

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If you have any comments, corrections, suggestions or plain criticism
I would appreciate it if you would communicate the same to me.

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[email protected]		www.robdempster.com

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