What Charger to Buy - Tesla, Zappi, Other?

[louco73]

I've been living without home charging since purchasing my M3P+ in December last year. I'm renting in an apartment complex that doesn't have anywhere to charge. The Tesla Wall Connector that I received with my car is installed at my parents place. That's allowed me to use that charger when visiting them, the Chargefox charger at Helensvale (Gold Coast), and a destination charger at Hope Island Market Place when grocery shopping. It's been fairly hassle free, plus the kids love going charging because they get to play games or use Trax. When I've had to go to the office in Brisbane I've used a car park that has a couple of destination chargers that meant city parking costs were minimal after the work discount and free charging.

Anyway, big changes are afoot after we purchased a house at the end of June and are now renovating it. I'm putting in 15 KW of solar panels with a 3 phase inverter. The solar will be fairly balanced throughout the day with panels to the North-East (dead in line with the winter sun) and the rest facing North-West. The property is North-East facing. The image below is taken from a solar quote that I received, to give you an idea.

The idea is to look ahead to when both our cars are EVs so that we have plenty of capacity and the ability to add batteries when they come down in price (hopefully in a year or two).

The large consumers of electricity in the new house will be a heat pump for hot water, induction for cooking, a pool pump, AC for cooling/heating and I'm considering an electric pool heater. I noticed from some YouTube videos that people use additional devices to orchestrate where the solar goes, e.g. battery first, then hot water, then car.

The Tesla Wall Connector Gen 3 is not available in Australia yet. I was hoping this would introduce an integrated experience with a Powerwall and solar to provide smart power management capability similar to the devices I saw in the YouTube videos. Since it's not available I wondered about the Zappi, given its ability to have multiple modes depending on what your situation is, e.g. grid time of use, grid plus solar, or solar only. The Zappi is a lot more expensive though.

I could probably just order another Tesla Wall Connector and manage the car charging by adjusting the amps to make sure I maximize the solar component of the charge.

Any advice, suggestions and experience welcome!

 

[Shallowal]

open EVSE along with "openenergy monitor" will track your solar export and divert power to your car just like zappi. In addition the openenergy monitor will monitor your whole house power usage and provide endless options for analysing the data. You do need to be interested in IT though.

 

[paulp]

Have a pool, 2 tesla, 30kw of solar and 3 powerwall.
Pool heating is hydronic cast within the pool floor. Its not overly usefull as its too slow and connected to the undefloor bathroom heating preventing me from heating both, even though we have ample solar to do that. I’m in the process of installing a madimack pool heat pump to look after the pool water more directly. Its only a couple of kw so will easily work off the solar
I dont really need to manage the car charging much other than in winter. I’ve found 8amp 3 phase works well, and on a nice day the powerwalls charge by midday, so realistically I can just charge the cars at any time on a nice day and fill them and the batteries....and still manage to export enough for another battery. I dont charge cars on an overcast day, and the only automation I need to consider for 9 months of the year is making sure the cars stop charging by the time the solar slows down, so I set the charging time based on the available hours remaining for good solar.
Winter is trickier as there just isnt enough solar, so nothing to manage as I dont fill the batteries so just manage car charging on a nice sunny winter day as I dont like to put fossil power in my tesla, but I just end up putting fossil power into the house instead. No amount of automation is going to change the solar output.
Hence unautomated is relatively easy to manage once you get into good habits.
Also a modern pool pump on low speed uses hardly any power and are quiet. If the house has an older pool pump its probably worth upgrading. Research ot well though. Also a cover for a heated pool is critical.

 

[begg]

I have 25 kw of solar a power wall and car. Agree with paulp and have green power so any power I must use in winter coming from the grid is clean solar or wind.

 

[Petergarrett38]

I one day hope to have the level of kit that Paul has but for now what I have is 10kw solar and a Tesla wall connector. I had survived similar to you, off shopping malls and carparks near my work for 12-18 months while living in Canberra. I recently moved to the GC and have always wanted solar so put up 10kw. The solar produces about 7kw on a sunny day and 3kw on a cloudy day. I set the car to start charging at 8am when the sun comes up and that works well for us. the solar charges the Tesla at 35km per hour and we rarely drive more than 100km in a day. At 12pm the pool pump kicks in drawing about 3-4kw and runs till 4pm. This strategy is simple and allows a lot of flexibility and maximises the amount of solar being generated to go into the car or the pool pump with any additional load or draw going to or from the grid. I played with the amps but found I ended up not working for us

 

[aegidius]

Do make sure the pool pump is one of the more modern variable speed ones. I replaced an old power hungry one a few years back, the new one throttles down to 500-600W usage after 5 minutes of fast running to get it going. You can also wire it into Tariff 31 off-peak power if you like and run it at night (as long as any timer it needs can be run on full-time power) but this makes it hard to select solar input for it.

I'm still on the old FIT so I don't ever charge during the day, and with only 3kW of solar I probably won't get much benefit anyway.

 

[louco73]

Thanks for all the replies and great info.

open EVSE along with "openenergy monitor" will track your solar export and divert power to your car just like zappi. In addition the openenergy monitor will monitor your whole house power usage and provide endless options for analysing the data. You do need to be interested in IT though.

I got quite excited about this, but they only seem to sell single phase products and I don't have the knowledge to build some of the 3-phase solutions I found. I can do software, but not the hardware .

Winter is trickier as there just isnt enough solar, so nothing to manage as I dont fill the batteries so just manage car charging on a nice sunny winter day as I dont like to put fossil power in my tesla, but I just end up putting fossil power into the house instead. No amount of automation is going to change the solar output.
Hence unautomated is relatively easy to manage once you get into good habits.
Also a modern pool pump on low speed uses hardly any power and are quiet. If the house has an older pool pump its probably worth upgrading. Research ot well though. Also a cover for a heated pool is critical.

I'm amazed that you don't have enough solar in winter with 30kW! What is the average kWh/day you produce during winter?

I think I'll just have to go without automation and use a similar approach to what you have outlined for now. and revisit it when I put batteries in at a later stage.

I haven't thought about a pool cover, but will check the options. I am getting a new pool pump and will check that it's efficient.

I have 25 kw of solar a power wall and car. Agree with paulp and have green power so any power I must use in winter coming from the grid is clean solar or wind.

I will have to look at the available plans and see if there is a green option that will work, but I think I'll have to get some data first to find the optimal plan.

I recently moved to the GC and have always wanted solar so put up 10kw. The solar produces about 7kw on a sunny day and 3kw on a cloudy day. I set the car to start charging at 8am when the sun comes up and that works well for us. the solar charges the Tesla at 35km per hour and we rarely drive more than 100km in a day. At 12pm the pool pump kicks in drawing about 3-4kw and runs till 4pm. This strategy is simple and allows a lot of flexibility and maximises the amount of solar being generated to go into the car or the pool pump with any additional load or draw going to or from the grid. I played with the amps but found I ended up not working for us

That's quite disappointing to only get 3 kW on a cloudy day with a 10 kW system. I've never had solar, so I'm not familiar with the drop off, but that is more than I was expecting.

I think I'll probably be pleasantly surprised how easy it will be to keep a relatively high charge and will adopt your and Paul's strategy.

Do make sure the pool pump is one of the more modern variable speed ones. I replaced an old power hungry one a few years back, the new one throttles down to 500-600W usage after 5 minutes of fast running to get it going. You can also wire it into Tariff 31 off-peak power if you like and run it at night (as long as any timer it needs can be run on full-time power) but this makes it hard to select solar input for it.

I do have the off-peak option and will consider that. Again, I think I'll have to get some data before I go down that path. I hope I have enough solar power to not need it.

 

[Shallowal]

EmonEVSE WiFi Connected EV Charging Station (Type-2).
You can select either single or 3 phase.
and
emonPi Energy Monitor - Solar PV Bundle

 

[Petros]

EmonEVSE WiFi Connected EV Charging Station (Type-2).
You can select either single or 3 phase.
and
emonPi Energy Monitor - Solar PV Bundle

That’s good info about this Zappi alternative but I note it’s price in Australia will probably end up more expensive.
I’ve had a 3phase Zappi for 2 months now and I can say it works brilliantly. After some teething problems were solved (great support) I’m getting truly sun powered day to day driving.

 

[Shallowal]

That’s good info about this Zappi alternative but I note it’s price in Australia will probably end up more expensive.
I’ve had a 3phase Zappi for 2 months now and I can say it works brilliantly. After some teething problems were solved (great support) I’m getting truly sun powered day to day driving.

The advantage of the EVSE is its integration with openenergy monitor for monitoring the whole of your house solar and electricity usage. It also has programmatic access for both monitoring and control, and via openenergy monitor can be monitored over the web.

 

[Petros]

... for monitoring the whole of your house solar and electricity usage. ...can be monitored over the web.

Actually the Zappi offers that functionality too. But it IS expensive compared to the other solutions mentioned above. Due to my house specifics the installation cost was over $1500.

 

[blaqmamba]

Hey Louco. I've got a 3phase installation of the HPWC at home and find it quite dumb that i can't easily adjust the amps etc from the app to maximise use of solar for charging. I reckon the scheduling feature in the are is pertty ordinary also. I kind of wish I'd just sold the HPWC and got a Zappi or similar.

So I suggest against buying another Telsa charger until they vastly improve the app control, and just get a zappi