Since I have excess solar power that is injected into the net for 0.01, I want to use this energy myself.
One of the options is to store the excess power into a waterboiler. To do this properly I am looking for a boilerdimmer that can be controlled by Home Assistant.|
This is already an old issue, some from many years ago. I am wondering if the industry is supplying the hardware to do this.
What I can find is dimmers that need additional hardware. I an looking for a Shelly-like product that can be controlled via Wifi/Zigbee and is capable of driving 16A of power.
Equipment I have found is either not driving that power, or needs additional hardware/cabling/etc to achieve the goal.
For variable power control you will almost certainly need a dedicated controller.
As my hot water is gas heated at around £0.07 per kWh and I get paid £0.12 to export, the additional cost is just wasting money for me, but I found this post that may provide helpful information.
Your use of the terms boilerdimmer and waterboiler as search terms in English may restrict you from finding your solution. Get a better translator...
Just saying.
Not sure why you need analog control. Thermal inertia means there will always be a large lag between adding power via your boiler and an increase in water temperature. Read up about hysteresis.
Basically, when you have surplus power, check your water temperature is under the upper threshold, and if it is, dump the excess power into it until it reaches the maximum temperature or you don't have surplus power. You do this by a switch, not a dimmer. Your boiler should have a thermostat to automatically cutout above a set temperature. Yes, this is standard industry practise.
Your heating element in the boiler should be rated correctly for the power you can supply to it.
You may need added equipment, both to sense water temperature, and to switch the power if these are not already part of your HomeAssistant setup.
What do you currently use to heat your water? What temperature sensor/controller is connected to it?
You could use a suitably sized SSR with an ESP sensor such as DS18B20 to modulate the power according to the loads and the tariff band, using it all year round. I think this is the answer you are looking for.
SSRs (solid state relays) are often expensive, especially if switching kilowatts and can often require huge heatsinks or fan cooling. A suitably rated magnetic style relay or contactor is often a far cheaper and reliable solution, and widely used.
This may already be part of the existing setup. We haven't been told.
The reason you don't find 16A dimmers is EMI regulations.
Last time I had a look, there were some commercial solar diverters around, expensive though.
Easiest and safest DIY setup that comes to my mind would be Proportional SSR combined with Shelly 0-10V PM Gen3. Has been successfully done on this forum.
Many people (me included) simply use esp board wired to triac module.
I made this dimmer with a shelly 0-10V dimmer, a 0-10V SSR I got from Ali-Express, and the HomeWizard P1 meter that reports the energy you consume or inject into the mains network.
If you already have Home Assistant, it is really cheap to build.
Carefull, you are working with real electricity, high currents, so your wiring must be good to avoid a fire.
