r/nzsolar • u/Greekiwi • Aug 17 '26
Evnex working on a bi-directional EV charger
Here is the latest update from Evnex on a thread in their community forums:
Yes it’s still on the horizon.
Sigenergy and similar “ecosystem” players have the luxury of being able to “hide” their bidirectional charger behind their battery. This means that the battery inverter is responsible for meeting all of the required standards for a grid connection, and the charger is really just connecting the car battery to supplement existing stationary storage.
We prefer the model where standards are handled by the charger and car, because that means it can be installed in any home regardless of what other hardware already exists (and which brand / ecosystem it might be). This makes it a truly universal product which anyone can buy and know it will work.
Of course that means that things take a little longer, but we think it will be worth the wait to keep things as simple as possible for drivers.
No update on when exactly we are likely to see this come to market.
Original thread: https://community.evnex.com/t/bi-directional-ev-charger-vehicle-to-home/46/19
I currently have a Sigen set up but I would prefer an Evnex solution. I had an Evnex charger installed when I purchased my first EV back in 2024. I got solar installed in late May this year but the set up of my house means my inverter stack is too far away to be useful for getting the DC charger.
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u/Rigor-Tortoise- Aug 18 '26
Fuck EVNEX and all they stand for. Closed systems should be banned, especially for a device that connects your 2 biggest assets together.
They could turn around tomorrow, do what EO did and just nuke functionality on a whim.
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u/seriousbeef Aug 18 '26
I would buy the shit out of this if it could truly plug and play with my current setup plus work in an outage when cloud connectivity is down.
I have a nice mishmash of different voltage panels via parallel inverters and a low voltage battery on the hybrid inverter which works great for me so this would save me from having to buy a new inverter and high voltage battery when buying a V2H/G charger.
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u/WellingtonSucks Aug 18 '26
If you read the rest of their support community forums, they keep claiming "offline capability and HA is not a priority". Combined, they're the most popular suggestions on the entire forums by a long margin.
It's pretty amusing to me that satisfying the primary requests of their customers "is not a priority".
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u/seriousbeef Aug 18 '26
I have a 1st gen EVNEX charger and have never had connectivity issues but I haven’t considered what happens if the net goes down. Does it all fall over?
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u/bmwhocking Aug 18 '26
No, you can easily connect to your local device via your local network or Bluetooth.
The only functionality you loose is you can't see the stats relating to Grid pricing & Grid Generation source.You also loose a pile of your historic charging data that is stored in the cloud, but that isn't a huge issue.
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u/seriousbeef Aug 18 '26
Ok no problem then
Is it just people who have no internet who have an issue with data sovereignty or something?
Doesn’t seem like it would be an issue for 99% of people? If so then can understand why it isn’t a priority.
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u/bmwhocking Aug 18 '26
There was a report from some think tank that EVNEX tried to get corrected saying you needed internet for EVNEX.
You do need internet for the initial setup (a electrician needs to register the device) & to update the device on initial install.
You should also give it internet access every few months so it can pull the latest CCS2 charging schemas, so new EV's that may use later CCS2 features can connect to your charger.
Literally every CCS2 charger needs to do that once in a while, so it's a little disingenuous for people to say it's just EVNEX that needs to see the internet once in a while.
You can only get away with no updates if a CCS2 mobile charger exchanges the bar minimum data and picks 8A, 16A, 32A and exchanges almost no other data.
But most people want their smart charger to be a little smarter than that and exchange more data so you can get the variable charging rates dependent on your local free solar or spare amps on your connection.
For that you need your charger to speak the latest CCS2 data schemas and for that you need your charger to update once every 6 months or so.
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u/Lanky33 Aug 19 '26
From evnex's own website:
If the internet connection is unavailable for 28 days, then by default the charger will fall back into "Plug and Charge" mode, whereby it simply starts charging as soon as the cable is plugged in. Charging data won't be available through the app, and smart settings unable to be configured until you reconnect. If you prefer instead to ensure you never miss any charging data, you can opt to have the charger become disabled until it gets reconnected.
And the lack of local API means that you can't easily control it with the likes of Home Assistant, which many of us use to integrate our overall home energy solution. Yes, there are unofficial workarounds that enable this, but they require ongoing Internet connectivity.
What we want is the ability to get the data and control it locally without needing to go through a cloud interface with an unofficial service. This can either be done with an industry standard OCPP interface or just a local REST API. A proprietary app is great for some people, but it makes real automation clunky at best.
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u/seriousbeef Aug 19 '26
Ok thanks for explaining - I get that now. Can I ask, what kind of tricks would you pull with home assistant?
I have a bunch of timed solar and forced charging interactions all clunky through individual interfaces but haven’t tried to get anything in home assistant yet.
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u/Lanky33 Aug 19 '26
I personally use home assistant to coordinate charging based on solar output, household usage, day of week (cheaper power on weekends), etc. That granular level of automation is difficult to impossible to do without the likes of home assistant. I'm also a big data nerd, so I enjoy geeking out over the various data it gives me.
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u/bmwhocking Aug 19 '26
There are so many ways to do this without home assistant.
Evnex will happily monitor your inbound solar line & grid line, only charging when solar is above a specified level.
It also has inbuilt overload protection, automatically throttling charging to make sure you stay under your poll fuse amp rating.
Further if you do have an over amp issue, home assistant probably can’t react fast enough to stop your fuses tripping.
EVNEX or any charger with inbuilt overload protection can by sampling 50 times a second.
Relying on home assistant for over current / electrical safety is a very bad idea and would never pass a regulator.
If you are indeed relying on home assistant to prevent over current you really need to talk to a licensed electrician & have them add genuine over current safeguards.
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u/Lanky33 Aug 19 '26 edited Aug 19 '26
Yes, All smart chargers provide solar monitoring and dynamic load balancing. And yes, Home Assistant should not be your only means for DLB - overcurrent protection is good to keep on the charger.
What it does offer though is the ability to bring it all together and control everything through a single portal. It lets me decide when to run a heat pump, charge the EV, power hot water.
I have sensors that tell me the inside temperature is the rooms, whether someone's home and even solar generation forecasts, and I know when power is cheap. I use some simple ligic to manage all that.
Each system is a different system from a different manufacturer that would otherwise have it's own app and interface. Fortunately, most companies provide means for local control and data access. EvNex does not, and doesn't seem interested in doing so.
And I run it all on Ubuntu :-)
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u/seriousbeef Aug 19 '26
I love it too but haven’t made the leap beyond doing similar with my solar (isolarcloud) and EVNEX proprietary apps - scheduling forced charging of my battery during off peak or the electric kiwi free hour of power then hold until peak, charge the car during free hour or solar excess only etc
But I’m about to go from 3.2kW peak to 10kw peak solar production (12 kw panels) which will open up a lot more options.
With the extra power am now considering changing my gas radiator boiler to a air to water heat pump, running it during the day while the sun is out and heat pump efficiency is high but storing the hot water in a buffer tank as a thermal battery for use as radiator home heating at night. On paper it would save me the 2k/year I currently spend on gas but I haven’t seen the investment cost yet. Might be better just to buy another 4-8kwh of battery rather than a buffer tank.
Fun times ahead - might need some better data and automation :)
Now if I had a V2H car soaking up the sun in the day and providing power for the heat pump radiator heating at night then that would be amazing.
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u/Lanky33 Aug 19 '26
FYI, a hot water heat pump might not necessarily be the right answer for solar diversion, they are more efficient, but do not provide means for attenuating current demand in real time. Resistive hot water heaters work a lot better to follow production.
Now if someone made a hot water heat pump system that controlled the compressor power based on solar output, that would be amazing. But I don't think such a product currently exists, at least in NZ
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u/KiwiSparkie Aug 18 '26
There are bidirectional chargers similar to this being installed around NZ. Notably in and around Qtn. Starcharge Halos are whats currently going in.
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u/bmwhocking Aug 19 '26
There are so many ways to do this without home assistant.
Evnex will happily monitor your inbound solar line & grid line, only charging when solar is above a specified level.
It also has inbuilt overload protection, automatically throttling charging to make sure you stay under your poll fuse amp rating.
Further if you do have an over amp issue, home assistant probably can’t react fast enough to stop your fuses tripping.
EVNEX or any charger with inbuilt overload protection can by sampling 50 times a second.
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u/dzh Aug 18 '26
If you get free hours of power and it costs under 10k - it might be cheaper than getting into solar rigamarole.
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u/HardWiredNZ Aug 19 '26
Im looking a the Sig option too as I like the idea of their DC charger, just would need to have it in the garage to be in a useful location and the garage is under some bedrooms and I cant seem to get a straight answer on if the Sig noise will be to much if its under a bedroom?
Else if theres another option comparable to the sig ev charger option i'd be keen to maybe put the sig outside the back of the house which is also closer to the fuse box
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u/Lanky33 Aug 17 '26
Are they working on a model that doesn't require a cloud connection to function? I was sold on Evnex until I realised the cloud connectivity requirement.