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Review: Myenergi Zappi EV Charger

In this post I’ll go over why I decided to get a charger at home in the first place and why I chose the Zappi, then show you how it works and what it’s been like using it for the past few months. Hopefully it helps you decide if the Zappi is the right EV charger for you!

Should I get a dedicated charger at home?

Let’s assume your regular commute is around 50km. To drive that distance in a Hyundai Ioniq, you’ll use approximately 7kW of the car’s 28kW battery. To put 7kW back in the battery using the household charger that comes with the car will take about 4 hours. Plug the car in overnight every two or three days and it’ll be full by the time you leave in the morning.

Using a normal power outlet with the charger that comes with the Ioniq.

You could even find a sneaky power outlet at work and leave your car to charge up there while you’re in the office. More and more shopping centers are getting public charging stations too, so you can top up for the week ahead whilst you’re doing your shopping.

Anywhere there’s a power outlet, you can top up your battery – it’s one of the great perks of owning an EV!

My driving habits require a bit more oomph when charging than what a common household socket can provide. It’s not unusual for me to drive 150km in the morning, come home, then drive another 150km in the evening. Relying on the included household charger just isn’t going to cut it, so a dedicated charger was worth it for me, even if just for peace of mind.

I’m going to live in my house indefinitely and I’m not going back to an ICE car, so I’m gonna use it for a while. If I was renting, or wasn’t sure I’d own a car long term, I may not have bothered to spend the cash to get one installed.

Why did you get a Zappi charger over others on the market?

I’ve got 6kW of solar panels on my roof and the Zappi is the only charger out there that will let me charge my EV purely from the sun. Why would I want to do that? 100% clean driving and to save money. It was an easy decision to go with the Zappi over every other EV charger on the market simply for those two facts alone.

How does the Zappi charge from solar alone?

The Zappi is wired in to your home’s electrical switchboard and can sense when excess electricity is sent to the grid. When set to charge in ECO+ mode, the Zappi detects electricity going out to the grid then turn itself on and start charging your car and match the charge rate to the amount of electricity currently being exported. Here’s a video of it in action:

If the sun hides behind some clouds or a kettle or dishwasher inside the house is switched on and there’s no longer any excess electricity going to the grid, the Zappi pauses and waits for excess electricity before resuming charging your car.

When the amount of excess electricity changes (e.g: 4kW of excess solar is getting fed into the car, but your home’s consumption increases by 1.5kW, then down to 1kW and back up to 2kW), the Zappi will slow down charging and ramp it up again in real-time so only the excess electricity from your solar panels is fed into the car.

What happens if the sun isn’t shining but I want to charge my car?

You can of course put the Zappi into FAST mode, where it just sucks full power from the grid as well as solar to charge the car as fast as possible, or in ECO mode where it will continually charge at a minimum of 1.4kW, drawing power from the grid if required. Toggling between the modes is easy, just press the Mode button under the screen.

When in ECO or ECO+ there are two additional modes: Boost and Smart Boost. You enable them by pressing the Boost button on the front of the unit.

Boost will temporarily disregard what your solar panels are doing and charge the car using power from the grid until it’s full. Smart Boost lets you set a specific energy amount (in kW) and time (e.g: 8AM) to charge the car to. The Zappi will use solar power only to charge, but if realises it won’t charge the car to the required level by the time you set, it will start pulling power from the grid to make sure you get the battery capacity you need by your deadline.

If your charging deadline changes from day to day, the Zappi even has a programmable boost feature. Where you can set weekly charging timetables. If you’ve got cheap off-peak electricity, you can also set the charging timetable to boost during off-peak only, so you can charge from the sun during the day and using cheaper off-peak electricity at night.

The Zappi’s manual has more info on all the different charging modes.

I personally just keep it in ECO+ and manually enable Boost mode before I go to bed if I know I need to go out somewhere the next day. It would be awesome if I could do this from my smartphone instead of going into the garage.

How does the Zappi save money?

It does, but not as much as you think. Here’s a snap of my Zappi’s charge log since it received its last firmware update:

67% of the electricity placed in my car came from the grid and just 33% came from my solar panels. It’s hard to say exactly how much of that 33% is due to the Zappi alone, as if I had a basic charger without the Zappi’s features, my car would still get some of its electricity from the sun when I plug it in on a sunny day.

For comparisons sake let’s pretend that the 211kWh put into the car from the solar panels was instead sucked from the grid at 19.459c/kWh – that would have cost me $41.05. I didn’t “save” $41.05 though, as if I charged at night instead and let the 211kWh of excess solar be exported to the grid, I would have received $28.45 (13.50c/kWh FIT) as credit on my bill whilst still paying the $41.05 for grid power. So in reality, I saved $12.47.

This means that when charging from solar power alone, I’m saving 5.959c/kWh (the difference between grid power & the feed-in tariff). If I extrapolate that using some rough math:

  • 635kWh used to drive 5,165km = 8.13km per kWh
  • 30,000km/yr = 3690kWh
  • 33% green charging = 1,217kWh from the solar panels only
  • 1217kWh @ 5.959c = $72.41 a year “saved” thanks to the Zappi

If your feed in tariff exceeds what you pay for grid power, you’re actually better off making sure none of that precious excess solar electricity hits your house or car and to export it all. I wonder if the Zappi could be configured to work in the opposite of ECO mode and only charge when there’s no excess solar generation?

Does the Zappi really reduce your carbon footprint?

I live in Victoria, which unfortunately still burns coal for the majority of its electricity (approx 700g of CO2 per kWh depending which way the wind blows or how hard the sun is shining).

According to the Zappi, I’ve placed 635.38kWh of electricity in my EV between 30/01/19 and 21/03/19 and according to the Hyundai SmartLink app, I’ve driven 5,165km in that same time period. If I charged purely from the grid, my driving would represent around 444.5kg of CO2. But thanks to the Zappi, 423kWh of that 635kWh total was from the grid, lowering the amount of CO2 to 296.1kg!

That works out to 57.33g of CO2 for every kilometer I drove – around half the CO2 of the Ioniq Hybrid or Toyota Prius (Green Vehicle Guide).

How fast does the Zappi charge an EV?

The max output of the Zappi is 7.2kW. It can be turned down lower (e.g: 3.2kW) if the circuit the charger is connected to is only 16A instead of 32A.

This charges my Ioniq from near empty (which is rare, but does sometimes happen) to full, in around 4 hours. If I come home with a battery at 60%, it only takes 90 minutes at full power to get it full again. 7.2kW is the max most EVs can accept via the AC charge port.

The handful of EVs that accept more 7.2kW that will be pleased to know that Myenergi has a 3-phase version of the Zappi coming soon that’ll enable up to 22kW charging with compatible cars (i.e: 22kW on the Renault Zoe, 11kW on the Tesla Model 3, 16kW Tesla Model S/X).

How do you use the Zappi?

  • Pop open the charge flap on your car.
  • Slide the Zappi’s plug into the socket.
  • Walk away.

That’s pretty much it, literally plug and play! Sometimes I press the boost button when I know there isn’t enough sun to charge the car. There’s settings and stuff you can tweak, but you only do it once when you set it up (the installer can help) and leave it really. I’ve not done any fiddling with it since it was set up.

How does the Zappi get installed?

The Zappi itself goes on a wall in or around your garage or carport and a power cable is run from the Zappi charger to your switchboard, usually on its own dedicated circuit. A separate cable is run from the Zappi to the switchboard for a CT clamp to measure your home’s electricity export/import. Obviously an electrician does this!

Here’s a quick video of the Zappi getting installed in a UK home:

If you can’t get a cable from the CT clamp to the Zappi or like me, you have three phase power, you need a little device called a Harvi. This is a wireless sensor that takes measurements from the CT clamp and sends it to the Zappi wirelessly.

The reason you need one of these for three phase power is because the Zappi only has two CT clamp inputs, but you need three CT clamps to measure three phase power. The Harvi has three inputs, so that’s the only way to get it to work. Here’s a pic of mine installed inside the Zappi itself so the signal is nice and strong (it didn’t reach the ~14m or so from my switchboard to the garage).

How much does the Zappi cost?

EVolution is the official supplier of the Zappi charger in Australia. The Zappi itself is $1,099 for a unit with a 5m long cord, or $1,199 for the 8m long cord. You can buy it online and they’ll ship it right to ya if you’ve got a sparky on hand to do the job for you.

EVolution can also give you a quote for installation if you aren’t friendly with an electrician. Just send them a photo of your switchboard and another photo of where you’d like it installed and they’ll reply with a quote.

I paid $875 to get my Zappi installed, in what I’d consider a pretty basic setup in a brand new house.

Compared to other EV chargers, the Zappi is very competitive. Jetcharge sell the Wallpod with a Type 2 cable for $1,320. EVSE sell the EO charging station with a Type 2 cable for $1,590. That makes the Zappi at $1,099 great value considering it’ll save you money and has more advanced features than the other two chargers!

If you’ve got solar panels on your roof and need an EV charger anyways, you’d be an idiot not to get the Zappi. It makes sure your driving is clean, saves you a little cash on the side by using your solar instead of exporting it and costs less than other chargers on the market. What’s not to love?!


Anthony also produces The Sizzle - a daily email newsletter covering all aspects of technology with an Australian point of view.

3 Comments

  1. Excellent review of the Zappi Charger Anthony< particularly it’s interfacing with your solar outputs. Thank you.

    I am curious as to the source of your “approx 700g of CO2 per kWh” for the Victorian grid? In looking at my own CO2 outputs here in Brisbane my then provider (AGL) could not provide me any data so I worked on electricity accounts that included the carbon price and the CO2 outputs calculate out at 1089g /kWh.

    The big thing about residential PV & EV that most people are completely unaware of is that a well sized rooftop system can completely offset all carbon outputs for both household and car transport. While only my wife an I at home now we produce 10%-20% more energy than we consume for both house and car (~20,000km/yr). Good to see you spreading this good news.

    kind regards,
    John Murray

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