A Smart Meter, a P1 Port and a Few Misadventures

In the first chapter of our home automation project, I explained how the announcement that our electricity meter was going to be replaced by a smart meter triggered my first round of research.

Very quickly, I discovered the existence of the P1 port: an interface that makes it possible to retrieve meter data locally using a small dongle.

Naturally, I wanted to try it.

But before I could plug anything into it, I first had to get the meter installed.

There.

If you are still wondering how a simple meter replacement can possibly deserve an entire article, we can continue.

First thing to know: get the P1 port enabled

A date is scheduled for the replacement of my old meter.

In the meantime, my research reveals one small detail that matters: the P1 port has to be enabled before it can be used.

And if you want it enabled, you may as well ask while the new meter is being installed.

In my case, doing it then cost nothing. The information I had at the time, however, indicated that having it enabled later would require another intervention and cost €25.

I still had no idea whether I would actually find the P1 port useful, but the decision was fairly obvious.

Enable it.

Worst case, I would simply never plug anything into it.

I also started wondering why the port was not simply enabled by default.

We'll come back to that.

Twenty euros? Worst case...

I had also started looking into what exactly you were supposed to connect to this mysterious port.

That is when I came across the HomeWizard P1 Meter, costing somewhere around twenty euros.

At that price, my reasoning was fairly straightforward:

Worst case, if it turns out to be useless, I haven't exactly lost a fortune.

HomeWizard, of course, has a whole ecosystem around it: an app, smart plugs, a small display for viewing energy data and so on.

So I ordered the dongle.

And a smart plug.

Why the smart plug?

Mostly...

To see what it could do.

All of this before the new meter had even been installed.

The big day

Eventually, meter replacement day arrives.

The appointment window is...

9 AM to 5 PM.

Eight hours.

I briefly wonder how people who cannot work from home are supposed to deal with that, but anyway.

At around 12:30 PM, the doorbell rings.

The technician has arrived.

I tell him I'll open the garage so he can access the meter.

And that is where the first surprise comes in.

He explains that he first needs to look at my existing meter to check whether he has the equipment required to replace it.

At that moment, I remember thinking that my grid operator's logistics system was rather impressive.

He looks at the meter.

Then goes back to his van to check what he has with him.

A minute later, the verdict:

he does not have what he needs.

And he is not even sure the required equipment is available at the depot.

At this point, I am becoming slightly... puzzled.

He tells me he will keep me updated during the afternoon and leaves.

Second attempt

At around 3 PM, my phone rings.

Good news: he has managed to find the required equipment and will be back in about half an hour.

Inner relief.

He arrives, I move my motorcycles out of the way to give him enough room to work — I'm nice like that — and the operation can finally begin.

He cuts the power, removes the old meter, installs the new one and puts the seals back on...

...then realises he forgot to enable the P1 port.

So the seals come off again, part of the installation is dismantled, the P1 port is enabled, everything is put back together and the seals go back on.

This time, it's done.

Almost.

Because inside the house...

there is still no power.

The technician insists there is:

— Your computer is running.

Yes.

My small server in the garage is indeed running.

It is on a UPS.

So I show him that no, the house most definitely does not have power.

His face changes slightly.

Meter number two

Everything gets dismantled again.

The technician suspects there is a problem with the new meter and goes back to his van to fetch another one.

Second meter.

Installation.

Seals.

Activation.

And...

Still nothing.

No power.

At this stage, I suggest that perhaps measuring the voltage directly at the meter output with a multimeter might be useful.

A slightly awkward moment follows.

That would indeed be ideal...

...except he has lost his multimeter.

An electrician without a multimeter.

Anyway.

— Don't worry about that, I have plenty of multimeters.

So I go and get one.

Meanwhile, the installation is opened up again and the seals come off once more so that we can access the meter output.

Measurement taken: there is voltage at the output.

So the meter is working.

We check the electrical panel. Nothing obvious there either.

And then I think about the solar panels.

Wait a second...

Let's check the protection system on the solar installation.

Bingo.

It had simply gone into protection mode during the outage.

In hindsight, perfectly logical.

Power is finally restored throughout the house. The technician can put everything back together — and apply what I hope are his final seals of the day.

I do not know whether I simply got lucky and met a particularly memorable technician.

But if every meter replacement goes like this, replacing the entire installed base may take a while.

So why isn't the P1 port enabled by default?

The question had been bothering me since my initial research.

Why install an interface that allows customers to access their own data and then leave it disabled?

One of the reasons put forward by ORES is data protection. Once the port is enabled, the information it provides becomes locally accessible, and the grid operator obviously has no control over what a connected device does with that information.

In some situations, I can understand the argument.

If several meters are installed in a shared room accessible to multiple people, leaving all their P1 ports enabled could indeed make it possible for someone to connect a device and retrieve data that does not belong to them.

In a single-family home like mine, I find the argument a lot less convincing.

My meter is inside my garage.

For someone to connect something to its P1 port without my permission, they would first have to get into my house.

At that point, I probably have security problems that are slightly more serious than the confidentiality of my electricity consumption.

But fair enough.

There is, in my view, a very simple way to preserve the principle of consent while still giving the customer a meaningful choice:

ask the question during the installation.

And explain what the port can actually be used for.

Not simply mention somewhere in a brochure that the meter has something called a "P1 port".

Imagine instead that, during the replacement, someone tells you:

We can enable your P1 port today. You may not have any use for it right now, but later it could allow you to connect a device to monitor your energy use locally, optimise EV charging, control a home battery or make better use of solar production and dynamic electricity pricing. Would you like us to enable it?

The answer can perfectly well be no.

But at least the question has been asked with enough information for the answer to actually mean something.

I would actually be quite curious to know what the activation rate would be if the P1 port were presented to consumers that way.

Because if you simply ask someone whether they want to enable a mysterious "P1 port" without properly explaining why they might want it, the most natural response is probably:

No, I don't need that.

Of course.

You have literally just told them it exists.

As soon as I understood what the P1 port could be useful for, I passed the information on to neighbours who were also due to have their meters replaced.

My advice was simple:

Get it enabled.

You may see absolutely no use for it today.

In a year or two, with solar panels, a battery, an electric car, dynamic pricing or simply a desire to better understand your consumption, things may look different.

Worst case, you never use it.

The port remains there with nothing connected to it and nothing changes in your daily life.

Best case, you save yourself another intervention and, in my case at the time, the €25 that came with it.

Nothing revolutionary.

Just the kind of information I would have liked to receive when the meter was installed.

Not every installer seems to do things the same way

A small anecdote was added to this story much later.

During a conversation with one of my neighbours, I asked him about his own meter replacement and whether anyone had explained the P1 port and its purpose when his meter was installed.

His answer was yes.

And not only had someone explained it to him, he had subsequently installed...

exactly the same HomeWizard dongle.

Now that is interesting.

First, because his experience was different from mine. It would therefore appear that not every installer presents the P1 port in the same way.

Second, because this neighbour is not particularly technical. He did not spend hours reading smart-meter documentation before the technician arrived.

Someone presented him with a possibility.

He understood why it might be useful.

And he used it.

Obviously, this is one person's experience. You cannot draw any broad conclusions about installation practices from a sample size of one.

There is another detail worth mentioning: in his case, the installation was carried out by a French subcontractor rather than directly by an ORES technician.

Does that explain the difference?

I have absolutely no idea.

But the anecdote does reinforce my impression that when people are given a concrete explanation of what the P1 port can be used for, some of them discover that they may actually want it.

Which, really, is exactly my point.

There is no need to enable everybody's port without asking.

Perhaps we simply need to ask.

And provide enough information for the answer to make sense.

The next day: finally, the toys

The following day, my HomeWizard P1 Meter and the smart plug I ordered with it arrive.

And naturally, like a child who has just received a new toy, I am not exactly going to leave them sitting in their boxes.

I plug the dongle into the P1 port.

I install the HomeWizard app on my phone.

A few standard Wi-Fi pairing steps later, everything is configured.

Five minutes.

Five minutes later, I had my electricity meter data on my phone.

And when I say five minutes, I am probably not exaggerating by much. If you have ever connected a few Wi-Fi devices before, there is really nothing difficult about the process.

The hardest part was probably making sure the dongle was properly seated in the P1 connector.

That is about the level of difficulty we are talking about.

I then configure the smart plug I bought at the same time.

Again, very straightforward.

And while playing with it, I realise that it is quite a bit more interesting than I had expected when I ordered it.

Yes, of course, it can be switched remotely.

But it also reports a whole range of information about the device connected to it: current power draw, voltage, current, energy consumption...

Well, well...

On one side, I now have the P1 Meter giving me a view of the electricity consumption of the entire house.

On the other, I have a plug that can tell me exactly what one particular appliance is consuming.

And control it.

That was not really why I had bought it.

But now that I knew...

Obviously, I was going to have to do something with it.

"Real-time", you say?

There is still one thing bothering me.

What interested me from the beginning was precisely the possibility of getting real-time consumption data.

Yet, in the app, it does not feel quite as real-time as I had imagined.

So I start looking a little more closely at how the P1 Meter works.

And that is when I discover something that significantly increases my appreciation for HomeWizard.

The dongle exposes an API directly on the local network.

I do not have to go through the manufacturer's app or a remote service just to retrieve the information.

I can query the little device sitting inside my own home directly.

Thank you.

Really.

I have a great deal of appreciation for manufacturers who still manage to build connected devices that are both reliable and open, without deciding that users absolutely must go through their cloud to access their own data.

And inevitably, my brain starts putting the pieces together.

On one side, I have the overall energy consumption of the house.

On the other, a smart plug that can accurately measure the consumption of whatever is connected to it.

And that same smart plug can also control the device.

You can probably see the problem starting to form.

So could I.

I'll just code something

My first reaction was fairly predictable.

I'll just code something.

A small application that queries the P1 Meter, retrieves consumption and production data, perhaps monitors the individual consumption of a few appliances and controls the smart plug according to a couple of rules.

Nothing too complicated.

At least on paper.

So I start looking around to see what already exists around the HomeWizard products, particularly how I might communicate with that smart plug.

And fairly quickly, I come across something interesting.

The HomeWizard ecosystem integrates very easily with something called Home Assistant.

Home Assistant?

What's that?

...

You see that little drawer that just opened?

Because behind that one, there were apparently a lot — and I mean a lot — of things waiting.

And I think it deserves an article of its own.