Consuming excess solar with smart plugs?

SolarSoGood

Hi all, 

I've recently had a 4.8kw solar system installed, I decided against a battery and hot water diverter due to cost and value for money. My inverter is a Solis S6 and has an app to monitor generation but not it seems consumption. I am currently using my smart meter to keep an eye on the exported energy.

I'd like to use the excess solar energy some times to power say a dehumidifier or electric heating. So for example:

If the solar excess is greater than 2kw turn on the heater socket, if its lower than 2kw turn it off.

Are there any systems that achieve this please?

Many thanks

paul991

cheapest would be a shelly monitor which is quite a flexible system I have used the second output of a water diverter to achieve this .would probably better to use a 750 watt heater this time of year and check the power your dehumidifier uses it may be a lot less 

thevilla

"Are there any systems that achieve this please?"

Yes. A solar diverter!  Just fit it yourself and choose the right heater etc.  Resistive heating with no "electronics".

I also use a raspberry pi to read my solar edge output via the API and switch on the dishwasher but that needs some programming skills.  Home assistant is another option if your inverter integrates with it.  Diverters are the easiest and imop most likely to deliver savings.

Krakkkers

I have a 4kwp system and my iboost diverter sends 1300 kwh to hot water each year if that helps your calculations on buying one.

1961Nick

I think the control gear to do what you want is too big to fit in a smart plug. The closest you are going to get is the suggestions above.

Petriix

You'd need a 'brain' of some kind to tell the smart plug when to switch on and off. If you're interested in programming then there are some options involving a Raspberry Pi but nothing obvious off-the-shelf.

Hot water diverters are highly dependent on individual circumstances as to whether they make any financial sense. Ultimately the question should be "how much hot water do I actually need and how much would it cost using my normal heating method?".

Finally you should factor in losing the export payment for whatever you self consume. It's often better to let it flow to the grid rather than waste it, say heating an empty room while you're out. The sums are very different for those of us on deemed export payments under the old FIT scheme. 

andyg9053

I bought a 2kw oil filled rad and a Tapo smart plug. I use my own brain and if it’s a blue sky I switch the rad on with my I phone, usually set it for an hour on timer in case I forget. Keep doing this every time I check on the weather

new_owner

solar assistant and/or home assistant would measure all the data.

Officer_Dibble

Rather more crudely than turning plugs on depending on excess generation (I couldn't work out a software solution to that one) I did for a while use the Tuya app to turn on smart sockets/immersion heater between certain times if it was sunny where I am. It never worked, as it never thought it was sunny. Until one dull day, when it decreed it was indeed sunny. The pattern continued. I can only think that its weather data was coming from a town of the same name somewhere in the US.

Officer_Dibble

Careful if you switch a dehumidifier with a timeswitch by the way - the desiccant ones (I think) don't like it - they need to shut down properly not just have the power switched off. Check your manual!