For folks living in South Australia, electricity is distributed by SA Power Networks. As an electricity consumer, you don’t normally deal with them directly. Instead you go through a retail company, of which there are a number to choose from.

SA Power Networks provide a service that allows you as a consumer to download your electricity data - Your Meter Data (you register for the service here).

Once you sign in you either download a PDF summary or a CSV file (in ‘NEM12’ format) with all your meter data, which includes both incoming and outgoing (like excess solar or battery) amounts.

I was keen to get that data so I could do some analysis of our power usage.

Having to repeatedly sign into that page and click on the various options just to download a CSV is a bit annoying. Ideally they’d provide a customer-facing API that I could call, but they don’t. (I presume they do provide an API for the electricity retailers).

So I wrote a .NET library and an example console application that will do all that for you from the command line. Source available at https://github.com/flcdrg/sapowernetworks-meterdata-net.

You just supply your email address and password (that you signed up to the Your Meter Data site with) and it will grab the CSV for you:

dotnet run --project src/Gardiner.SaPowerNetworks.MeterData.Console -- --email your@email.com --password 'YOURPASSWORD' --file data.csv

If all goes well, will produce:

Logging in as your@email.com...
Logged in successfully.
Found 1 NMI(s):
  200012345678  Home  STREET SUBURBNAME 5000
Fetching data from 2026-08-18 to 2026-08-20...
Saved detailed NEM12 CSV to /Users/david/dev/sapowernetworks-meterdata-net/data.csv

The data looks something like this (truncated):

200,1234567899,E1B1,E1,E1,,LG1201234567,KWH,05,
300,20260619,0.00000000000000,0.00000000000000,0.00000000000000,0.00000000000000,0.00000000000000,
400,1,154,F19,,
400,155,288,A,,

And what about Home Assistant?

Hey, wouldn’t this be a great data source for integrating with Home Assistant? You could use it to import your electricity meter data directly into HA. Well yes it would, but as nice as my console app is, it’s written in .NET and Home Assistant integrations are written in Python.

So I used Copilot to create a new Home Assistant integration that imports the data each day automatically! It was able to use the .NET implementation as a reference and created equivalent Python code that would work with Home Assistant.

The source for the integration is at https://github.com/flcdrg/sapowernetworks-meterdata-ha. For the moment you will need to add that as a custom repository in Home Assistant HACS, but I’ve submitted it to be listed so that you will be able to just search for it in the HACS store.

The integration provides a control and a number of sensors:

But because all the data is historic, it doesn’t provide a sensor with the current reading. Instead it publishes the historic data to Home Assistant’s Recorder as statistics.

One way to view the data is via a Statistics graph card.

eg.

- type: statistics-graph
  entities:
    - sapowernetworks:9999999_import_e1
    - sapowernetworks:9999999_export_b1
  days_to_show: 7
  period: day
  chart_type: bar
  stat_types:
    - change
  logarithmic_scale: false

Which can give you a graph like this:

The blue ‘import’ is the electricity that came from the grid into the house. The yellow ‘export’ is excess solar power that was exported back to the grid.

The Saturday 19th and Sunday 20th were both beautiful sunny days here in Adelaide. The reason for the differences in the amounts on those days is that Saturday I was out driving most of the day, so we did not charge our car during the 11am-2pm free period that our current electricity plan offers. But Sunday once I got home from church the car was plugged in and recharged, so for that period while it was just as sunny, that solar power was going straight into our car instead of being exported.

As part of the discussions with Adam from LAMM Solar and Electrical, I mentioned that we were getting an electric vehicle and I was interested in getting a home charger for faster charging. After clarifying that I wanted nothing to do with a certain T*sla brand, they recommended taking a look at an Evnex charger.

We only have single-phase power in our house (and no immediate plans to change that), so that narrowed it down to one of their E2 range that can provide up to 7.4 kilowatts:

The Flex is the base model. It doesn’t have the ‘Solar smart’ feature that allows you to “schedule your charging to use only your excess solar power without drawing from the grid, giving you free kilometres from sunshine”.

The Core sounded like it was the one, but I took note of Adam’s advice to always get a longer cable than you think you’ll need, as you won’t regret it. Some chargers let you plug in your own cable, whereas unfortunately the Evnex ones don’t. That pushed me to the ‘Plus’ as rather than 5m it comes with an 8m cable. It also supports a client/server model which I understand would be useful if we wanted to get a second charger installed and they could be managed together.

I was also interested to see what kind of ongoing support they had - I found there’s an active support forum with prompt responses to queries, so that was also encouraging. They’re designed and manufactured in New Zealand. If I can’t buy Australian then New Zealand is the next best thing!

And so that’s what we got. We ordered directly from Evnex and it arrived a couple of weeks later, just in time for LAMM to install when they refreshed our solar panels (there was a small reduction in costs for doing both together).

Oh and Adam was spot on with the longer cable. 8 metres was enough that I could run the cable along the ceiling of our carport over to near the charging port on our car. Keeping it off the ground and avoiding a tripping hazard. 5m would have been too short to do that.

Mobile app

Evnex provides a mobile app that you can view and manage your charger.

For comparison, here’s the Kia app at the same time:

In the Evnex app you can view the details of the current charging session (and past ones too)

Like the solar inverter, the Evnex also uses a CT clamp to monitor actual electricity usage in your house. I’d say ‘current usage’ but that could be confusing🙂

You might just want to be able to charge any time, but for me I wanted to limit charging to when our electricity plan is cheapest. It is true that the Kia app provides simple scheduling for when to accept charging:

But the Evnex app has much more advanced controls:

The app has an advanced schedule setting, where you can configure when you want to allow charging and the costs that it would incur (from your electricity plan).

My current electricity plan has free power from 11am-2pm, so that’s the main time I allow the car to charge. But on occasion I may want to allow charging overnight (when it isn’t free but the cost is low) so I’ve created 1 hour intervals that I can selectively enable if needed.

You can add in different prices.

And for each time period you can assign one of three behaviours:

If we had a larger solar installation, then the Solar Smart feature could be useful too, to manage how much of your solar-generated electricity to allocate to EV charging.

Charging done (set to stop at 90%):

Home Assistant

Yes, there’s a really good Home Assistant integration for the Evnex chargers. It provides two devices:

There’s a number of controls and a bunch of sensors

You can use these to track usage and generate some nice graphs. I can imagine you could get quite clever with using Home Assistant to provide even finer control over how your car is charged. I could see something like monitoring the weather forecast to predict likely future solar generation to adjust how and when charging is offered. Not something I’m going to do now, but there’s all kinds of possibilities.

Money back

Narelle discovered that our local council were offering a number of sustainability rebates, including for installing your own EV charger! We just had to supply a before and after photo of the installation and then a week or two later we got $200 back. Nice!