I have built my first online electricity calculator. It’s very simple and there are lots of similar calculators out there but it’s a start.

Behold: Electricity Calculator

Here’s how it works. Let’s say you are wondering how much it would cost to run a nightlight if you leave it on all the time. This nightlight has 0.2 watt LED, so you enter 0.2 as wattage.

Next you enter 24 as the number of hours per day. Here in Australia we pay 30 cents per kilowatt-hour on average. The calculator gives you the result: the running cost would be $0.53 per year.

Another example. We have 6 light bulbs in our kitchen. They are CFLs (of course) and 14 watt each.

So in total they use 6 * 14 = 84 watt. We have them on for about 3 hours per day. We pay 40 cents per kilowatt-hour. According to the calculator the kitchen lighting cost us $3.02 per month or $36.79 per year.