Do you have the POWER!!??

by Rory Milne on December 15, 2020

Current state of power

Power usage, electricity demand, green energy, Eskom, load shedding, inverters etc ….
Daily conversation topics for South Africans. But how do we actually get involved and take action within our homes? First lets clarify what we have control of and what we dont!
Eskom Supply You are at their mercy
National demand You are at the mercy of your fellow man
Home Solar You have limited daytime power
Home batteries You have limited reserve power
Inverter You will need this to use solar or batteries
 Consumption You can manage this 
If you have invested in back-up power it means that you have a buffer to get through load shedding, which is great. That buffer is directly proportional to your battery capacity. Many South African are even going fully off grid, using renewables (usually solar), to generate their own power. Enough power needs to be generated during the day, to ensure sufficiently charged batteries, to get through the night. Or perhaps even, a few days of cloud.
The cost of an off-grid solution is directly proportional to your daily power demand.


We face four main constraints or limitations:

1) The actual ongoing availability of utility power to our homes and business’s

2) The rising cost of using the utility power

3) The large upfront cost of backup or off grid power

4) Your ability to be more eco-friendly


Whichever constraint is most relevant to your situation, a single approach can positively impact all four of these factors. This approach has to be to reduce your consumption. Reduced consumption leads to 1) reduced reliance on utility power, 2) reduced electricity bills, 3) ability to thrive with a smaller scale backup system and 4) improves the eco-friendliness of your home or business.

But HOW!!??

I need to shower every day with geyser heated water. I will die without my morning cup of coffee! I can’t braai every night, the stove and oven can’t be binned! At night we need lights! I have a security system that can’t be turned off! How can I reduce usage without messing with my lifestyle?


Well, step one is analysis. What makes up my electricity usage and bill? When is power being used? What appliances are using the most power?

There a smart meters around that show you live usage and total usage history. But to have a real understanding you need to be able to break out the known offenders. I.E. The Gesyer!

In South Africa, a geyser is commonly about 40% of your power usage.

You should be mindful of anything that heats! Its guaranteed to be a high consumer.

But you need to know some usage trends, and how it impacts your total consumption.

If you boil the kettle once a day for your coffee, it’s gonna be tough to reduce that. But if its being boiled multiple times a day and not utilised properly, it’s worth rethinking the way it is used, or even the type of appliance you use.


The Efergy power monitor is widely available in South Africa and will give you decent feedback about your power consumption. You can monitor your whole home, via local screen or even remotely.  Find out more here.

The Sense power monitor has a really innovative approach to monitoring whole home power consumption. Unfortunately with that innovation comes some problematic quirks. It does seem to be well suited to the South African market. But worth a read up if you are bored . Find out more here.


Step two is control. Once you can see a breakdown of your usage, you can choose what needs to be on and when it should be on. You can identify opportunities like turning off appliances when you are not at home. (I.E. Heating, cooling) Only heating the geyser to meet your needs, most of us don’t need hot water 24hours a day. Optimising your pool pump usage.


Step three is automation. Our lives are too busy to be faffing with all this! I want to do this stuff, but it needs to be EASIER! The steps above are not ground-breaking. The challenge is actually taking action & remembering to take said action every day, every time you leave home, every time you go to bed etc. This is where automation comes in, your geyser should be on a timer that suits your needs and be easily overridden when required. When you leave home, you should be presented with an option to turn off all unnecessary appliances with one touch. When you return home stuff should reactivate when you arrive, but if you want to pre-heat/cool prior to arrival, that should be easy too! When you retire for the night, one touch should put your home in a “sleep” mode that suits you. When you wake up, your home should wake up with you.

Automatic action and broad-based control with single touches, results in efficiencies that actually add up to something meaningful.

Cool, but you still haven’t told me HOW!!??

There are multiple devices around that will help you monitor power usage and many more that give you control of switches and lights.

The Shelly 1PM is a smart switch with power monitoring built in. As standard it runs on the Shelly platform, but can be flashed with Tasmota firmware or integrated into Home Assistant directly. Find out more here.

The Sonoff POW R2 is a smart switch with power monitoring built in. As standard it runs on the eWeLink platform, but can be flashed with Tasmota firmware or integrated into Home Assistant. Find out more here.

Anything above 15amps becomes a bit trickier but is solvable with the integration of some heavier duty kit. A few options from the Shelly range, can control relays in your DB Board enabling you to control and/or monitor, entire circuits.

The Shelly EM is a power monitor with dual inputs of 50Amp and 120Amp each. It also has a built in relay switch, so coupled with an external High Amp relay, can control power any circuit. As standard it runs on the Shelly platform, but can be flashed with Tasmota firmware or integrated into Home Assistant directly. Find out more here.

The trick is to gather the information and control from around your home and bring it into a central place. It’s not helpful to have to jump from app to app…

We use Home Assistant to achieve the objectives set out above. Central monitoring, central control and automations that consider all the homes sensors. As well as the ability to incorporate multiple brands and systems into one place is what really rounds off the potential of Home Assistant.


Home Assistant is our platform of choice. It is also open source, so you can do it yourself. 

If you want Milney to help you achieve something EPIC, give us a shout on the website.