Challenge: Saving money on my Electricity Bill WITHOUT installing Solar.
The example: My monthly bill is R3 700 on average. I want to control 2 fridges, 3 geysers, 2 air fryers, 2 kettles and 2 sets of household lights in such a manner that I can save at least R740 per month on my electricity bill.
The Experts Answer from Stratlec: R3,700 a month is a substantial bill, even by 2026 standards. In South Africa, where tariffs have been rising aggressively, you are likely consuming roughly 850–950 kWh per month.
To get your bill down, we need to focus on the “Energy Big Three”: Heating, Cooling, and Phantom Loads.
We will be using Shelly automation devices from local online store, Stratlec – based in Gqeberha, to bring that bill down. Remember – if you can measure something you can control it.
1. The Strategy: Where your money is going
Before we buy hardware, we have to look at the “low-hanging fruit.” In your specific list, the 3 Geysers are likely responsible for 40% to 50% of your entire bill.
- Geysers (Priority 1): These are “thermal batteries.” They lose heat 24/7 (standing loss). Automating them to only heat during peak usage times (morning/evening) is your fastest path to ROI.
- Fridges (Priority 2): You don’t “turn off” a fridge, but a Shelly allows you to see if a compressor is failing or if the door is being left open, which causes massive spikes.
- Lights & Small Appliances (Priority 3): Kettles and air fryers use a lot of power ($2,000W+$), but they run for very short periods. The savings here come from ensuring they aren’t left on or drawing “vampire” power when not in use.
2. The Shopping List (Hardware Estimate)
To control your specific list, here is the setup we recommend using Shelly Plus and Pro series devices.
| Item | Recommended Device | Qty | Est. Cost (Total) |
| 3 Geysers | Shelly Pro 1PM (DIN-rail mounted) | 3 | ~R2,700 |
| 2 Fridges | Shelly Plus 1PM | 2 | ~R900 |
| 2 Kettles | Shelly Plus Plug S (Easiest) | 2 | ~R1,000 |
| 2 Air Fryers | Shelly Plus Plug S | 2 | ~R1,000 |
| 2 Lights | Shelly Plus 2PM (Controls 2 circuits) | 1 | ~R550 |
| TOTAL | ~R6,150 |
Please Note: This is estimated hardware cost only – you still need to get an electrician to install the devices. The DIY part of the devices is more to do with configuration.
Note: For the geysers, it is highly recommended having an electrician install a contactor alongside the Shelly to protect the device from the high inductive load of the heating element.
3. The Math: Calculating your Payback Period
Let’s look at the projected savings based on a R3,700 bill.
Assumed Savings Rate: By aggressively scheduling 3 geysers and killing standby power on the rest, a 20% reduction is a very conservative estimate. Many users see up to 30%.
R3,700 x 0.20 = R740 per month savings
Payback Period Calculation: Using the estimated hardware cost of R6,150:
After 8 months, the system has paid for itself, and you are effectively putting R740 back into your pocket every single month.
4. A Pro-Tip for your Air Fryers & Kettles
You mentioned wanting to control 2 kettles and 2 air fryers. Honestly? Don’t automate them for the sake of “saving energy” alone. * A kettle only uses power when the button is pushed.
The real advantage: Use the Shelly to set a Schedule or Timer. For example, “If the Air Fryer has been on for more than 60 minutes, turn it off.” This prevents house fires and accidental energy waste if someone forgets it’s running.
5. Why the 3 Geysers are the “Rub”
In a 3-geyser house, you often have geysers fighting each other. If all three kick in at the exact same time, you hit a “Peak Demand” spike. If your municipality uses Time-of-Use (ToU) tariffs, those spikes cost you double. A Shelly system allows you to stagger them (Geyser 1 at 4 AM, Geyser 2 at 5 AM, Geyser 3 at 6 AM) so you never hit those expensive peaks.
Visit https://stratlec.co.za for more info and product listings.
