For the last 12 months I have been trying to reduce the amount of electricity I use at home. It all started in August 2008 when my electricity bill arrived and my average daily usage was 19.54 kilowatt hours (kWh)!
19.54 what? To put this into context, in 2003 the average daily usage for Victorian households was 6,398 kWh, or 17.48 kWh a day. Whilst I am certain that figure has gone up in the last five years, I imagine I am using at least (if not more than) the average daily household usage. With only two adults in my average sized home, this is excessive!
Immediately I forked out for compact fluorescent lights (CFLs) to replace my energy hungry incandescent globes. I also reshuffled some hard disk drives between two computers that were on 24/7 so that one could be shut down and only powered up when needed. The last change was to replace two of the hard disk drives in my 24/7 media centre PC with one ‘green’ hard disk drive.
These changes resulted in a welcome surprise on my next electricity bill. My average daily usage was down to 15.33 kWh – a 21% decrease. By being energy conscious (switching off lights and appliances when not needed) the third bill came in at 13.47 kWh – another 12% decrease.
It was now summer 2009 – air conditioning season. I have a split system inverter air conditioner, and I decided I would monitor my electricity usage more closely to see how much it used. On the infamous Black Saturday I consumed 24.56 kWh, and probably played my part in the blackouts that followed.
Over the next few months I monitored my usage every week or so, with my average daily usage coming in around 15 kWh. After returning from overseas in July, I decided it was time to reduce my usage even more.
Using a watt meter I checked all the appliances in my house to see what was using… errr… watt. The biggest users were my media center and web server PCs (~1.6 kWh a day each), and also the fridge in the kitchen (1 kWh a day) and the freezer in the garage (1 kWh a day).
The biggest surprise came from my study, where I have a PC and printer that is rarely used, and is shut down when not in use. I estimate that it is powered up every 3 weeks, however the standby power that it consumed whilst off was high – 40 watts or 0.96 kWh a day! It is now turned off at the power point, resulting in 0 kWh a day.
Other appliances I tested included the front loading washing machine (4 watts when switched off at the machine) and the cordless phone base station (6 watts).
The final change I am making is to replace the last of my energy hungry lighting – the eight 50 watt halogen downlights in my kitchen and dining area. In total they consume 0.4 kWh per hour, or 1.6kWh a day if they are on for four hours each night. I have had two of them replaced with CFL type downlights that consume only 11 watts each as a trial, however I am already sold and will organise to have the other six replaced ASAP.
The changes I have made in the last month have brought my usage down to around 13 kWh a day. I have set myself a target of 12kWh a day, which I think can be easily achieved, will save me money in the long run, and reduce my need for the grid.