Cheapest Way to Get 2 x Chargers Installed for Solar, Please Advise!

blobert

Hello,

We're about to finish a new build house that has 3 phase electricity and a lot of solar power.

We're running 2 electric cars, a Nissan Leaf and Tesla Model Y (if it ever arrives!)

While in theory I could get a 3 phase charger (I think the Tesla will do 11kw) they are expensive. I think it also makes sense to have either a dual charger or 2 chargers as otherwise we'll have to switch between the 2 cars (or more realistically my wife will keep unplugging my car and plugging in hers, leaving mine never getting charged!)

As we have a lot of solar power (about 40kw) we'll be doing pretty much all our charging that way.

The electricians are in wiring the house at the moment so I'm looking to work out a quick and cheap solution.

I know people here are fond of the Zappi chargers but they are pretty expensive at about €1,000 each.

As we're planning to use Shelly switches for some basic automation (ie to put the solar power into heating, heating hot water etc) I was thinking we could also use them to control 2 less smart chargers and make them smarter (ie just charge when solar power is available)

So if we got 2 x QUBEV (seem to be cheapest with decent reviews) like these: https://evonestop.co.uk/products/qubev-ev-charging-unit-type-2-socket-32-amp-7-2-kw-ip65

And have them controlled by the switches (ie charge cars when solar available) I'm thinking it might be the cheapest/simplest way to do what we want. If they both charge at 7kw (our Leaf does 6.6kw) that should be fine in terms of putting a decent amount of power in at once.

I'm guessing we can only apply for 1 x Grant for this (I think with the older system both cars might have been eligible for chargers)

Let me know if this plan sounds ok or if there is anything else better I should be considering?

I see there is a cheaper 17th edition of the QUBEV charger and an 18th. It says "18th Edition variant comes with RCD + MCB and Enclosure. 17th Edition will need to purchase this separately if required." So I'm not sure which will do the job here?

Andy advice would be much appreciated!

unkel

You now only get the €600 EV charge point grant if the charge point is smart. So back to the zappi with ya 😁

A zappi 3ph is barely any more cost than a single phase, so I would strongly urge you to go for that. Your future cars might even have 22kW AC charging, charge it up from your solar PV in just a few hours on a good day!

Also I would just install one for now based on the info you have given. But when are the cars at home, both during the day? Or just one?

Gumbo

Zappi is 3 phase.

as is the Tesla charger but it won’t integrate with PV.

Wallbox is 3 phase as is ohme and EO Mini Pro.

eltoastero

Would it be possible to gets a single zappi charger, unteathered, then get the longest type 2 cable you can so it could charge either car regardless of how they're parked (so instead of moving the cars around to charge, you just move the cable)?

I'm pro-zappi (3 phase if you've got the wiring) as it would then meet your other needs in terms of diverting excess power to the hotwater tank (via the Eddi), it load balances (via harvi ) and its configurable via the myEnergi app to prioritise where the excess energy goes. Also, i've found their customer service to be rock solid for years.

zg3409

Ideally you get two zappis and set one up as priority so one car gets priority and when it's full the other car can complete. I don't you will have 14kW (7+7) and do one solar compatible and one non solar compatible might work. Beware if using home batteries as zappi may not work well with home batteries as it turns on only based on export amounts, not how fully charged the battery is.

Nit installers may get discounts on zappi. You may need a good wifi signal at the charger for it to work and a separate sensing cable to fuse board and or esb meter may be needed along with other things like a zappi compatible got water diverter.

Gumbo

https://www.boards.ie/discussion/comment/120300710#Comment_120300710

That’s what I do. 7.5m cable means I can charge the Tesla or the 530e without moving them.

the_amazing_raisin

Honestly, I'd just get a pair of Zappis, they'll do the job and the alternatives aren't really much cheaper

Currently I'm running an EO Mini and a Zappi. The way it's working at the moment is the EO charges the Leaf overnight, and the ID.4 is plugged into the Zappi and charges from solar. I'm only boosting the Zappi at weekends at the moment because I want to see how long I can get on PV only

You could have a similar approach and just charge one car from solar at a time, and have a dumb charger for the other one when needed

blobert

Thanks very much for the replies guys.

Both cars are at home during the day most of the time.

I think you're probably right about the 3 phase charger if it's not that much more expensive. It probably also makes sense to max the amount of power going in at times of day when there is generation (looking outside now it's very sunny but I bet it wont be in a few hours) and to futureproof (we'll probably be living in this house for decades)

Maybe we could start off with just one of them (with a long cable as suggested) and have a system of when you unplug your car you plug in the other one and see how that goes. We would always add another one when/if someone inevitably does not stick to the simple system!

I see some mention of the Zappi needing wifi. Is this definitely required? This is going to be located a decent distance from the house so I would not be 100% confident it will get a good/any signal.

Also with the Zappi is it relatively easy on the unit to override the solar charging, ie if you come home of an evening and need to recharge by morning can this be done with the push of a button or two on the unit?

I'd actually contacted the MyEnergi guys about more general automation of the house but there was an issue with the Eddie in that it only diverts up to 3.68kw which would work for hot water immersion but not for our underfloor heating (which is electric and about 9-11kw). This was why I was going down the route of the Shelly products.

Thanks again

slave1

I also agree with two Zappis, you can run Cat6 to the Zappis alongside the required power cables along as your Zappi is the new generation which is the only generation they currently supply. This will eliminate any WiFi concerns.

Honestly, go for the two Zappis now and run CAT6 cables, at least 3 pairs. I'll show you in the next post (from the phone) what your system could look like

slave1

Example

Paul Kiernan

Surely the requirement for Zappis is redundant since the Feed-in tariffs came into play! If you can get much the same rate on the FIT as you pay for night rate are you not just as well off to charge at night and let any excess solar go to the grid?

unkel

https://www.boards.ie/discussion/comment/120301959#Comment_120301959

FIT is chargeable at your marginal rate of income tax (if over the €200 threshold)

A stupid decision by the government if they want us to feed the grid. Now we are feeding our cars, hot water and massive batteries instead. Nah - na - nah!

Paul Kiernan

https://www.boards.ie/discussion/comment/120301967#Comment_120301967

That's mad, Ted! I hadn't realised that. It's nonsensical! You should only be taxed if your FIT exceeds your own usage i.e. you're a nett exporter.

axe2grind

Also, current FIT rates are not indefinite. When they change, i figure they will drop.

the_amazing_raisin

https://www.boards.ie/discussion/comment/120301285#Comment_120301285

To override the solar you can set a timed boost

For example I've got a timed boost set between midnight and 8am for the night rate, this will charge at full power (depending on the grid setpoint) during those times

So I've got the timed boost set for Friday and Saturday night in case I want a full charge in the ID.4 over the weekend

The charger will still be in Eco+ mode and will divert solar assuming there's a car plugged in that can take a charge

I'd say get one for now and see how you go, but you can kind of set things up for a second one by running additional cabling if needed

slave1

https://www.boards.ie/discussion/comment/120301959#Comment_120301959

What's the OP going to do with 40kWp ? That's serious level of electricity even for 3 phase. Best to self consume

unkel

https://www.boards.ie/discussion/comment/120301998#Comment_120301998

Even then you shouldn't be taxed at all. Micro generation is a great way for the state to dodge some of the responsibility of developing electricity generation infrastructure. At zero cost to the tax payer!

Only commercial solar farm should be paying tax, but then again they can first offset all their capital costs and running costs against feed in income

the_amazing_raisin

https://www.boards.ie/discussion/comment/120301967#Comment_120301967

Isn't the whole point that they don't want us to feed the grid but to self consume? The FIT was done in such a way that you'll never make money from it, unless perhaps it's part of a farm business

slave1

Small arrays will self consume, the bigger the array the greater difficulties in self consumption (April to Sept)

the_amazing_raisin

https://www.boards.ie/discussion/comment/120303664#Comment_120303664

They'll just need to get a 100kWh battery then 😂

slave1

Already have 144kWh of battery between house and EVs, will still be exporting but absolutely fine with that, come high PV days even a 100kWh home battery wouldn’t handle our daily PV generation (anticipating 90kWh daily highs)

zg3409

https://www.boards.ie/discussion/comment/120301285#Comment_120301285

The eddi has extra outputs to drive other things. If you get someone knowledgeable to set it up in theory it could trigger underfloor heating but note solar is maximum in summer when heating may be off. Also unless underfloor can operate at low power it may kick in and draw more power than solar is putting out.

I would plan carefully to minimize power consumption, home heating is probably biggest expense. If heat pump can heat water then don't use normal immersion for hot water. If you have a fairly long commute or regular trips then try fill cars from the sun.

At least put in wiring and control cables to allow 2 x zappi, in terms of wifi that's needed for the app, and to allow you to switch from sun only charging to fast charging while in bed etc. In terms of monitoring house load ideally use a wire cable to load sensor in main fuse board, this triggers the charging when exporting from solar.

In theory zappi can be used with no control wiring but it's more complicated and then you are relying on wireless and zappi has a non wifi 868mhz signal to a wireless load sensor or to talk to eddi. Ideally you want heat pump, zappi and water heating to all be adjustable do the right one gets priority particularly for spring autumn months where solar may vary hour to hour.