Posts Tagged ‘Electricity’

Electricity Monitoring Part 2

Wednesday, October 13th, 2010
This entry is part of a series, Electricity Monitoring»

I previously mentioned that I have an electricity monitor and that I wrote a program for collecting the data and uploading it to a central database.  Actually, since then, Google have launched Google PowerMeter.  Fortunately, their API is freely available and so I have uploaded my data into their system (fortunately this was a fairly straightforward XML upload job) and switched to using the Current Cost software for uploading to PowerMeter.

PowerMeter is fairly good, although it does have some annoyances.  However, between that and the other software that I used to use of my own, I have managed to reduce our daily elecricity consumption from about 23kWh to around 11-14kWh.  We pay 7.57p/kWh, so that translates to an annual saving of roughly £275.  We’ve done this without making any major changes to our lifestyle or habits and it doesn’t involve driving yourself mad over little things.  We’ve also done it without switching to compact fluorescent bulbs which I particularly dislike.

Without doubt, the most significant cost savings came from switching off a second freezer which we had running in our shed and from replacing our faulty fridge with one that works correctly.  However, there were were other things that we’ve done that add up to a fairly large amount of electricity saved over time.

The most useful thing that I did was spent a couple of hours one morning doing an electricity audit – working my way around the house working out how much electricity different things use in different states.  Basically, I did this by unplugging everything until the monitor showed zero constantly and then plugged things back in one at a time.  Be careful when you do this if you decide to – make sure no one else is in otherwise you’ll drive them mad and also don’t take too long over it if you have a fridge and freezer otherwise your food will go off!

I found some interesting things, some of which fit in with what other people say and some are surprisingly not mentioned by anyone.  I went as far as measuring different states for several devices – on, standby and off.  That’s one interesting thing – people don’t mention that a lot of devices do use power and in some cases a significant amount of power when they are off, even if they are not in standby.  I’ll write more about this in future posts.

Entries in this series:
  1. Electricity Monitoring Part 1
  2. Electricity Monitoring Part 2
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Electricity Monitoring Part 1

Thursday, April 15th, 2010
This entry is part of a series, Electricity Monitoring»

This is a rather different topic to my usual posts.   A few weeks ago, I invested in an electricity monitor.  In case you haven’t come across them, they are little devices which monitor your electricity usage and display useful information, such as your current and historical usage.  Because I am a programmer, I did a bit of research to find one that I could access the data on and ended up with a Current Cost ENVI-CC128, although I did also need to get the USB Data Cable to connect it to my PC.

I was quite impressed with how easy it is to connect the transmitter (it just hooks around a specific cable going into the electicity meter (you can get extra transmitters – it can take up to three if you’ve got a 3 phase supply or multiple meters)).  The USB cable has practically no documentation though, other than a little information on Current Cost’s website and a total lack of understanding what I was asking for from their technical support people, which is a little odd, considering that they don’t actually supply any software with it themselves – you have to find it yourself or write some.

I worked out fairly quickly (with a little help from Googling other people’s experiences with the CC128) that the USB connection works as a simulated serial port which spews XML out when it receives a reading from the transmitter (usually every 6 seconds).  It also spews out totals every hour, but I haven’t bothered with those yet as I have a machine running the whole time, so I am currently just logging the readings to an SQL Server database as they happen.

I’ve also written a nice little program using ComponentOne’s charting component (C1Chart) so that I can specify a date/time range and get a graph of usage, either by individual reading or grouped by minute, hour, day, month or year (eventually!).  This has provided me with all sorts of interesting information, and given me a good picture of our electricity usage.

Entries in this series:
  1. Electricity Monitoring Part 1
  2. Electricity Monitoring Part 2
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