Computing stuff tied to the physical world

Smart metering

In Hardware on Nov 29, 2012 at 00:01

JeeLabs has entered the 21st century…

The electricity company just installed a new “smart meter” – because they want to track consumed and produced electricity separately, something the total count on the old Ferraris-wheel meter cannot provide:

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See that antenna symbol on there? Its green LED is blinking all the time.

At the bottom on the right-hand side is an RJ11 jack with a “P1” connection. This is a user-accessible port which allows you to get readings out once every 10 seconds. It’s opto-coupled with inverted TTL logic, generating a 9600 baud serial stream from what I’ve read. Clearly something to hook up one of these days.

The gas meter hanging just beneath it was also replaced:

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Why? Because it sends its values out periodically over wireless to the smart meter, which then in turn sends it out via GPRS to the utilities company.

Apparently these gas counter values are only reported once an hour. Makes sense, in a way: gas consumption is more or less driven by heating demands, and aggregated over many households these probably vary fairly slowly – depending on outside temperature, wind, humidity, and how much the sun is shining. Not nearly as hard to manage as the electricity net, you just have to keep the gas pressure within a reasonable range.

Electricity is another matter. And now it’s all being monitored and reported. Not sure how often, though – every 2 months, 15 minutes, 10 seconds? How closely will big brother be watching me? First internet & phone tracking, and now this – I don’t like it one bit…

Welcome to the 21st century. Everything you do is being recorded. For all future generations to come.

  1. That new gas meter has options to talk proprietary or Zigbee.

    Interesting that the battery life is quoted as 15-20 years.

    Someone peeking over your shoulder for low power techniques? ;-)

    • Maybe not so hard – at one packet per hour? Getting the node down to say 3 µA in sleep mode would mean it needs only around 500 mAh over 20 years (but that battery better have a low self-discharge!).

    • Nice catch btw – thx for the link.

  2. Couldn’t you refuse the new meter?

    • I was told I had to have it replaced, because we will be a net producer of electricity – and I do want to get the associated refund.

  3. They also could tell by the Ferraris meter reading being lower than last year. Privacy comes at a cost and a twist of the arm. Neighbourhood production and consumption counteract. Why wouldn’t be one electric substation smart meter not be enough? Can that gas meter report net production? ;-) Are you sure these two meters -despite the warning on the sticker- can’t shut you off from the net? Hack! I mean, Heck, as you say, Big B(r)other.

  4. I think that they were monitoring your work at JeeLabs, and were just jealous that you could monitor all of your stuff, and they couldn’t.

  5. @eljonco – a scan of the gas meter brochure shows an option for a remote controlled shutoff valve! Surprising indeed. Continuity of domestic gas supply is a fundamental safety issue – continuous supply pipe pressure and flow prevents inwards air diffusion (avoiding build up of a deadly mixture of gas and oxidant).

    As important is avoiding risky user interaction – will all appliances really get shut off during an outage? Restoring supply without this knowledge is far too dangerous – usually some mechanical lockout is incorporated, requiring “knowledgeable” user intervention to restore the supply.

    A curious imbalance – the Gas company can only control consumption through a very long feedback cycle of after-the-fact billing. The Electricity company can fade, sag and ultimately make rotating blackouts to control consumption dynamically (as Eastern Japan is now experiencing due to the aftermath of Fukushima).

  6. @jcw, agreed – the RF side can be very low duty cycle. But the gas bellows counting mechanism is a … unique (sic) “Gray-Code” high frequency optical detection system

    Must be using similar tricks to those discussed on the Forum for reducing the power budget of at least two IR diode/detector pairs.

    The classic permanent magnet/reed relay method is out of favour due to it’s vunerability to abuse from another technology leap involving rare earths.

  7. “Why GPRS?” is what crossed my mind. The utility has dozens of other options to signal the meter. Most of them would require digging up your powerlines and tapping into them to listen in. So why cell phone technology thay has been proven to be compromised?

  8. Regarding the shut-off fear: In NL utility companies for gas, electricity and water actually CAN already shut off individual homes with switches/valves on their end of the line. They won’t need smart meters to do so for them. Those smart meters only just make it easier, because they won’t have to send a guy over to “flip the switch”.

    Also, the risks of power outage become smaller if you have your own solar panels etc. Your power would simply be out at night. It would be like living with rolling blackouts as suggested before.

    So just stock up on an emergency terrace heater to cover the case where the gas shutoff valve gets triggered.

  9. Not sure how often, though – every 2 months, 15 minutes, 10 seconds?

    I’m currently working on a piece of energy reporting software for a large Dutch company. Enexis (the energy grid maintainer) provides us with metering data at a 15-minute resolution. Your smart meter will probably allow for “live” tracking of your energy consumption. So, I guess it will be somewhere between 15 minutes and 24 hours.

    What I’m wondering here… How will you be credited for the energy you pump back into the grid? I’ve heard that energy retailers do not credit the taxes over produced electricity. A Ferraris-wheel meter would just run backwards when you’re producing electricity, which means that the produced electricity is subtracted from the consumed electricity at the same price. A smart meter can measure consumption and production independently, allowing different prices for consumption and production. This is probably the real reason why the electricity company replaced your meter…

  10. If you are concerned about your privacy you can request Stedin to disable the smart part of your smart meter. ( By doing so they are not allowed to remotely read-out your meter anymore.

  11. @jcv: If you have now the current smart meter, there is a good reason to make a new low-power current pulse sensor that send every 5 minutes the consume and the actual power :-)

  12. I’ve been fooling around a bit with this P1 port, and it’s quite interesting. Nice output; could be useful for monitoring your own electricity consumption (and production). One of the benefits of a smart meter…

  13. @jeroen, these differential tariffs are a growing concern for home production. Different countries have different policies – the credit for production can be quite poor (or confused like the UK where there is a credit for all production and an extra but small credit for feeding excess into the grid).

    This gives an interesting option – when you have a generated excess, turn on (or modulate) local load(s) to consume it. Large capacity energy stores like water heating come to mind.

    Taking the theme further to storing in a resusable form (e.g. battery bank, inverter) usually is sadly not economic once the true cost of periodic battery replacement is computed.

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