JeeMon is a little web server / database / reporting tool I wrote a while back. It has been in use at Jee Labs for over a year now. Here is the electricity use for 2009:

Couple of glitches, such as incorrect readouts when power failed and the sending node got reset to zero counts.

Here’s the gas consumption for 2009:

Gas consumption (heating and hot water) is relatively high for this house, which is an open split-level design with lots of windows. Well isolated, but there’s simply no way to keep heat from rising up through the open stairways.

Here are the temperature and humidity readings for the past month:

These are commercial S300 and KS300 sensors, and they seem to have frequent glitches. It looks like those could easily be filtered out, though.

Still, we managed to get €600 back on the 2009 energy bill, and with about 3000 kWh and 2000 m3 we’re 30% below the average consumption in this residential neighborhood, for both electricity and gas.

Being aware of what’s going on makes a difference, IMO. It has become a habit to turn off all the lights when I leave a room, and closing curtains right away when it gets dark. When we go out, we turn down the thermostat. Who needs high tech, when common sense is all you need? It’s so obvious, yet so effective …

The JeeMon database for all of 2009 is 26 Mb, i.e. tiny when considering that this includes every reading and some aggregated series as well. In fact, it contains a lot more data than what’s shown in the above graphs.

I’ve got several ideas and plans for JeeMon in 2010. I want to make it far more modular, so that nearly all its current functionality becomes available as easy-to-extend plug-ins. And it needs to be fullly configurable – as it is, JeeMon is still little more than a one-off implementation. But it has served its purpose very nicely already.