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by jonathanlydall 23 days ago
It depends on what you need to be "smart" about your house. If you live in an apartment there is not much to be automated. However, (if like me) you live in a free-standing house with solar panels, possible power outages and all heating done through electricity, a PHEV you want to charge, being able to have smart energy management is actually very useful.

Ideally my house should have 3 phase power, but I'm not yet inconvenienced enough to go through the headache of getting this organized. This means that at any time my maximum power draw can be 13.8 kW (60A at 230V).

Generally this is enough, but I have on occasion tripped my mains due to drawing too much at a particular moment, I have the following significant power draw items:

- 4x underfloor heating circuits at 3kW each.

- 2x electric geyser at 2.5kw each.

- Electric oven and induction stove, not sure on amount but I think they can collectively pull 6kW easily.

- Pool pump at 0.6kW.

- Inverter re-charging batteries at night (I only have 10kWh of storage and want backup power at night in case of a power outage), I can configure maximum draw here, but could probably pull up to 8kW if I wanted.

- PHEV at 3kW.

When we had regular load shedding here (South Africa) it was very easy for the power to trip if I didn't manage things, particularly if I left underfloor turned on in the winter at night. What would happen is that power would have been off for ~2 hours, then comes back and everything on a thermostat would turn on AND the inverter would start charging its battery.

If I proactively turned the floors off then I wouldn't generally have an issue.

Even without a power outage, it is possible to trip things when using stove/oven with underfloor heating turned on or if both the geysers happened turn on their elements at an inopportune moment.

IoT can allow this to all be managed, it can have rules like:

- Don't run ALL the underfloor heating circuits at the same moment, alternate between them.

- If the stove/oven is in use, don't turn on the element for either of the geysers, it can wait.

- Temporarily stop charging the PHEV or inverter's batteries until there is less power demand.

- Temporarily turn off the pool pump if it would help.

It can also create other opportunities around solar energy production, you can do things like have only "excess" energy go into your (PH)EV provided it has a minimum charge level.

Other automations which I wouldn't mind:

- Exterior lights on a schedule based sunrise/sunset.

- When I'm away it would be nice to be able to remotely turn on/off particular interior lights and open/close curtains at particular times of the day.

What I actually have automated:

- My alarm system has (not great) app, I have wired it up to my garage door so I can remotely let in the armed response security company in the event of the alarm going off and I'm not at the house.

- I use the Tuya ecosystem to automatically turn my geyser and pool pump off on a schedule and if there is a power outage or load shedding. This allows me to heat the geyser still even if there is a power outage and it's the middle of the day with lots of sun on my solar panels.

HA is something I want to look at one day (when I have more time), meanwhile the Tuya ecosystem is very useful considering its minimal amount of time investment required.