Thanks for your comments. I see your point – and that’s exactly why I decided to create my ‘arduinometer’ project. It’s (hopefully) one day going to be an open-source metering platform for utility meter monitoring, all off the same board.

I’m not sure of the TED 5000’s capabilities, but I’ll certainly take a look – it sounds like an interesting piece of kit. Using the Lego NXT was a cool idea, too. It certainly must be frustrating to have a gas meter that you can’t read very easily!

An inline sensor probably wouldn’t be allowed in the UK, on the pipeline side (that’s usually owned by the gas transporter), but in your own property, providing it is fitted by a registered/qualified gas installer you’d probably be OK – though you’d need to check that. It would be great if there was a passive means for reading the usage, as you suggest.

For now though, I think your options are pretty limited. Either contact your gas company and ask for another meter (preferably one with a pulse output or at least the opto-reflective disc) or perhaps you could explore the possibility of using a cheap web cam and a laptop to do pattern recognition.

It should be relatively simple to write a program capable of recognising the digits in sequence on your gas meter; you could take an image every 1s or so and process the digits into an integer and compare it against the last reading. When it changes, you can update your meter value. That would probably be a very accurate way to read your meter, too.

Whatever path you decide to go down it’d be great to hear about your progress so please feel free to get back in touch and share your experiences.

Thanks for stopping by!

Richard.

My goals are:
* record gas and electrical consumption
* get the data into Google Power Meter
* extend pre-built components where possible
* keep the price low

I am looking at a new electrical metering device called “TED 5000″ (in the US only, for now, I think). It has an Ethernet port, power supply, an on-board web server, an API of unknown capability. I am quite sure the data from this device can easily be coerced into Google Power Meter. So this device would seem to solve many aspects of the problem.

So getting the gas data seems to be the problem. My meter doesn’t have much in the way of a readable interface. It seems to be readable via RF, but I can’t find any way to get at that data — otherwise, it’s just an odometer-like counter on the front.

I did a different experiment — using a Lego NXT (usually for building robots I hooked up its light sensor and had it take and record whether it could see light every 5 minutes. Then I put the device so it could see the flame from the furnace and let it run for a day, and then another day for the water heater.

The readings were clean, so then I had to figure out how much gas was used — I used the BTU/hour rating on the devices. After doing a few days of these readings and calculations, it looked like it was roughly accurate — it tied out pretty closely to what the gas meter recorded. (Here’s a link to my blog post: http://fivepercent.us/2009/02/26/heat-and-hot-water-energy-usage-for-my-house/)

But there has to be some better, yet still inexpensive way to measure gas flow. I am not sure if there are any inline meters available to home owners — they would probably be expensive and I would need to hire a gas fitter to have it installed, and then I would still need to read the data.

I wonder if there’s some device similar to the induction-based meters like the Owl, Cent-a-meter, and TED that could measure gas-flow non-invasively?

Anyway, I am glad I came across your site. What you’re doing is very cool.

Tom

I am considering putting a new meter in the house, with a pulsed output

http://www.gasproducts.co.uk/acatalog/G4_Gas_Meter_with_Pulse.html

Which won’t be too expensive to install I hope.