Solar panels at home, worth it?

May I ask who your provider is?

My rates are substantially more than that and I've just switched!

I wonder will that 27c per KWH that they are paying last much longer..

We put in 12 panels and a battery earlier this year. Two electric cars and to be honest we see very little return from them. The battery was a waste of money becaise the car drains it in 45 mins. I think solar panels are great for homes that use a normal amount of electricty but once you get into charging EVs they are hopeless. Still, they do save you a bit of money. Just don't bother buying a battery.

I think a battery makes if you charge it at night rate electricity while also charging the car at night. Use the battery during the day when the panels are not giving you the power your house needs. Of course the battery needs to be depleting each day for it to make sense. Using it to charge the EV seems senseless to me.

You need to ask the people here who know how to utilise it best so you benefit from it. A good start would be what you got installed and maybe post it in another thread like this one https://www.boards.ie/discussion/2058222496/solar-for-dummies/p75 not my call on the thread name!

FYI,

it’s winter now for me and I’m charging my battery to 100% every night, and it will not start depleting until 8am when the night rate ends…

for the last 6 weeks I was only charging it to about 55%…

Just because the battery isn’t being used by yourself to its full ability, it doesn’t mean you should rubbish the idea of having a battery…

But it’s an opinion based on use of the system that isn’t maximising it’s potential… He’s waiting for sunny days to charge his battery, which he won’t get again until March/April…. So yes, doing that is a bit pointless and does make a battery pointless and not worth it…

its 8:11am and my battery is at 99% because there’s no chance the sun will run the house until around 11am if I’m lucky…. Then when that happens and production meets demand, the battery will stop depleting and whatever’s left will be for late afternoon when solar production stops completely in the hope that there’s enough juice left in the battery to make it to 11pm when the night rate starts again…

If I was doing what the op was doing, then I’d agree that batteries are a waste of money…. But as I actually use my battery to its full potential, I’m the complete opposite and think a battery is an essential part of a setup (especially in Winter)

Solar Thermal or Solar PV?

I will take a look at your video. If there is a quick solution to change the settings based on the time of year or changes in routine, I will definitely take a look into it.

Charging the battery at night is tricky because this is when we charge our EVs and both cars are very different. One will charge within a few hours and the other takes quite a long time, usually 7 hours or more if it's close to empty. In the morning the battery is completely depleted and this time of year stays at around 18% all day as there is very little light. The rest of the house generally runs off the panels as long as an electrical applicance isnt on. There is however at least one person in our house all the time.

We could in theory set the battery where it doesn't feed the house during the night but if a car is plugged in, the battery won't top up anyway so we aren't gaining from topping the battery upon our night rate.

For a short period there in August/September, the energy companies where playing it smart and putting customers on a standard rate with a four hour window at night to charge their car at around 8-11c. It was very hard to find a good standard day, night and peak rate. On this particular plan, the battery was useless as it made more sense to top up the battery during the day using the panels because the night rate was too short and again, our cars used up all that energy anyway.

We are back on a 11pm-6am night rate and it would be great to top up the battery on our night rate but from what I can see this is virtually impossible if you are charging cars with an EV plugged in every night from 11pm-8am. Maybe I'm wrong, but I know when we used to schedule charge one of the cars, if something else in the house was turned on during the night the car would stop charging, probably because of load balancing I expect. I honestly can't see a 67-77kwh car battery charging from 15% to 80% overnight and the house battery being at 90-100% the next morning in this weather. Somebody prove me wrong.

I think the difference here is that everyone in your house is out during the day. This is when batteries work best. Nobody at home, the battery tops itself up during the day. Am I wrong? When do we top up the battery if a car is plugged in every night from 11pm-8am and the house is busy all day with dishwashers, electric heaters and induction ovens? The battery is always empty between September and March. We consume about 50kwh per day this time of year.

We know a retired couple. No EV. No kids in the house. There all day. Cooking for two people. One wash a day max. It's a different story for them. The battery works well and they see credit on their bill every month.

I go back to the point that this is about how solar panels and batteries work for households in the future. We live in a big house. No oil or gas. No fires. Two electric cars. We consume a lot of electricity. We gain nothing from having a battery and very little from solar panels during the winter. It's not how our system is set up. We properly planned this with the solar panel company. It all comes back to usage. The more we move away from traditional heating methods and running fossil fuelled cars, the more households will see less benefits from Solar panels. They barely put a dent into our bills and the battery was a waste of money. It's too small and the sole reason for one is that it can be topped up by the panels. In Ireland we are topping them up on our night rate which is completely ludicrous as our unit rates are so high at the moment. I expect most people aren't even shopping around for a good rate either.

I will look into the night charging thing because honestly our battery doesn't top up with the car plugged in, particularly the car with the bigger battery. Everything gets directed at the car. In the summer the battery tops up early morning with the extra sunlight.

Is disagree about battery being a waste.

Dad got a 10kwh fitted with 5.2kw PV. He charges it during the boost rate, exports all Solar he’s not using and as a result has not used an imported during the day since it’s being running. Payback is really good

look at going on. A boost rate as supposed to just D/N and charge it between 2am and 4 am or what ever boost times you get

Are you sure there's no App? I had Solis inverter with Solis App (same as Andy's screenshot) and you could change the charging windows on the app.

Re the cars; you have 2 cars, do you really charge them both, fully, every night? Either way, on an 7 hour window that you currently have, that's about 70kWh + available in that window. So fair enough, if you are charging 2 x 50kWh car batteries from ~20% up to 100% every night there isn't space for a battery to charge. But anything less and there is.

I echo Andy's comment, I think a few tweaks to your system and your battery will be really useful.

IF you set the battery to charge between 11pm and 6am (the same time period the cars are charging), it will be charged at the same time. And it wont start to discharge until 6am.

If you only charge one car per night, there absolutely is capacity to charge your battery every night too. (Without knowing your exact setup, I think your battery would actually charge first before car if there was a conflict of demand as the load management of the charger would kick in and stop charging the car until the house load went away).

You can set is using the inverter menus like Andy's video shows. you can do it through the app as described here also:

I like to charge mine as slow as possible to reduce stress on it and help prolong its lifespan…

my night rate period is 9 hours… so why fast charge it in 2 hours when I can charge it much slower over a longer period, and try to help it last as long as possible…

I had a feeling it wouldn't be a simple change in the app. I'll take a look.

While we’re on the topic of charging multiple items during a boost, charging car, charging battery(s), running heat pump. And perhaps a dishwasher.

would this be overloading, new house so wiring will be fine.