Solar for Beginners [ask your questions here]

I'm running home assistant on a pi, have zappi and givenergy integrated. I guess I could have an automation which would kick in when the zappi is charging at full rate to limit the battery discharge. I guess it might have ended up costing me slightly less by discharging the battery into the car as id have charged it as a cheaper rate..worked out ok as it was a sunny morning and solar topped it up pretty quickly again

I am thinking about getting additional panels installed on a south-facing roof. I'm thinking that additional panels could help with charging an EV (future purchase). We already have a 5.8 kwh install split 50/50 on east-west, but could get possibly an additional 3-5 panels on the south facing roof, bringing the total capacity to 8 kwh. I have a few questions that hopefully someone might be able to advise me on:

• Would we get sufficient benefit from the additional panels - it would probably cost an additional 3000-3500 euro to add 5 panels (using existing 5k inverter), I would need optimisers on at least one of the existing string arrays as it would be a 3 way split if my understanding is correct.
• I reckon I can get the panels for around 200 euro each. I have some spare racking I can use from the original install so our costs should be just for the actual install and electrical. Are there companies that will take on that work without supplying the equipment?
• Would I be better using the money to install an EV charger instead?

Any advice would be greatly appreciated.

I presume that's 2.9kWh per day? That seems to me to be very low? If that value is right and you then install a 4.1kW system, then while the solar system may be a larger number than the average daily consumption (and aren't actually measuring the same thing), you'll still have a shortfall of energy as you're not storing it onsite and because much of the energy use occurs outside of the typical times when solar is generating. So in your case you'd export much of the solar back onto the grid (and get paid for it), but you'd still have to import units in the evening and overnight.

Let's say that you use 2.9kWh over the course of a day, this equates to 121Wh per hour (2.9/24). If your 4.1kW system generated 2.0kWh over a period of 1 hour in the day, 1.879kWh would be exported to the grid. Hence for that one hour you would not have to pay for electricity at all.

If you stored much of this excess energy in a battery then you would be able to consume that energy later on in the evening and night, but at a higher total cost due to the outlay for the battery.

So I'd summarise this to say that while the FiT (feed in tariff) remains high then solar-only with no storage is worth-while, but not if the FiT degrades over time.

Makes sense?

Thanks for replying - it's actually 2900kWh per year so based on your calculations I'd be using about 331Wh per hour so it would be cost effective while it was generating solar electricity. I'll do some more research but I assume I could add a battery at a later date if necessary?

Yes you can if you go for a hybrid inverter. There are other technologies for doing it too, but hybrid is the best option in many ways.

It will add X% more than you produce now. So let's pretend you've 10 panels and you produced 1000kWh in a given time period. You'll now produce 1.1 times that. Or another way - if you've 8 panels now, divide last months kWh by 8 and multiple by 9 and that would be what it would of produced with that extra panel. Assuming it's the same orientation.

Yes.

10.6 kWh for me on a 3.1 kWp install. Set up 1.7 kWp South and 1.4 kWp West, so should get less than you as the west panels make less.

What wattage and orientation are your panels? All south facing.......

I'm lucky enough to have got solar panels installed by my local housing authority but I've received no information about them so I have a few questions.

I have 8 panels and have recently installed solis app today I've yielded 9kwh. Is this good?

Does any excess energy I don't use get added each day and reflect on my bimonthly energy bills?

Have you got a battery? If you do you can charge it at night if you have a day/night meter in winter to get cheaper use during the day. You can use the Solis cloud app to remotely control the inverter if you have a generation 3 data logger but you need to contact Solis support to get access.

euservice@solisinverters.com There's more data you can see on the app by pressing your plants name then press device then press the long serial number and you have more details there including the option to control the inverter remotely by pressing the 3 dots on the top right if it's activated.

I'm getting solar installed in October, with battery and EDDI. Is there anything I can be swotting up on in advance as there seems to be a lot of tweaking that can be done on systems.

I am getting ~ 10 Jinko 430 KWh, Solis inverter and Dyness 5KwH battery. I have a smart meter and day/night rates. I also have HA set up so might be looking at the options to incorporate that.

Just would appreciate any advice on what areas to look at to get up to speed.

Thank you so much for this. Ironically I am already with Flogas but it will be up in January.

nice one! can you describe your solar system a bit - size kwp, make of inverter, any other bits & bobs

the inverter app typically is just for information but the ability to control the inverter is getting more common now. is this what you mean by 'make things more efficient'?

It depends on the make of the heat pump. Mitsubishi has 2 settings for hot water, standard or eco mode. Eco mode will use less electricity but take a little longer according to the manual.