Monitoring power use

Web based electricity monitoring

Our online tools offer a sophisticated but convenient way to keep tabs on your energy consumption. This services allows you to:

  • track your household energy usage by month, hour, dollar or power unit (if you have a smart meter)
  • view your latest bill and make payments
  • set alerts and budget limits to help manage your usage
  • receive daily or weekly energy use reports
  • manage your account details and update them at anytime.


Simple formula helps calculate power hungry culprits

The following formula helps to work out the estimated power use, and cost, of any appliances in your home. And you don’t have to go through the cost of installing even the simplest plug-in monitor.

Start out with the watt value of an appliance (usually marked on the appliance itself). Then apply the following formula:

watts (of your appliance) x hours used per day ÷ 1000 = the daily kilowatt per hour (kWh) usage

Once you have this information, you can multiply the kWh by your cost per kWh (use a cost that includes electricity authority levies but excludes daily charges).

For example: 1000 watts (average clothes iron) x 0.25 hours per day ÷ 1000 = 0.25 kWh per hour x 27 cents per kWh (theoretical electricity supplier’s price) = 6.75 cents per day.

In effect, your ironing is costing you on average 47.25 cents per week (about a $1.89 per month).

For more information about watts used by various appliances, visit Otago University Energy@Home