The Basingstoke energy Monitoring Project

To reduce our bills – this is the challenge.

Our electricity and gas meters are mounted outside in little cupboards (the white things on the side of the house).

The goal was to find a cheap way of constant monitoring the consumption as a precursor to trying to reduce it, in order to to do our bit for the environment and our wallet too.

The Gas Meter

The gas meter was changed recently, and the index has a little rotating magnet on the thousandths of a cubic metre dial. A little reed switch is mounted under the dial – one operation for each 0.01 m³

The Electricity Meter

The electric meter was more problematic as there was no tidy way of getting a pulse output from the meter which is the old fashioned electromechanical type.

So I bought a couple of second hand domestic meters from a Meter-R-Cheap shop in Devon. These have a blinking LED which neatly blinks once for each Wh consumed, I.e. 1000 blinks per kWh. To start with I connected one of them up to a board, in order to experiment with getting the LED coupling working.

Above you can see a phototransistor stuck to the electric meter with some blu-tak. This has now been replaced with some double sided tape, and I dare say that other mechanical solutions will be tried later.

I have now fitted the meter permanently to the fuse box, so that it records all power to the house. This was a pig of a job as the meter tails are very thick, and it looks slightly crooked. However, the electrons don't seem to notice.

I have now put together a little c application here which reads the port and updates rrdtool dtatabase which generates the graphs.

2008