GEM, New Zealand's favourite power tool.

Take control of your power usage with GEM, the Good Energy Monitor; a clever online tool
that gives you a clear picture of how much energy you're using and what it's costing you.


Track your usage and costs

Compare your usage to similar homes

With GEM, you can track your energy usage by bill and by year. If you have a smart meter, you can even see how much you've spent by day and each half hour.
For the first time you can see if you're using more, less, or about the same amount of energy as homes that are like yours.

Set a goal and develop a savings plan

See how temperature affects your bill

GEM allows you to set an energy savings goal, track your progress over time, and gives you tips to help you save.
With GEM, you can see how temperature and seasons affect your energy usage.

Unusual usage alerts

Predict your bill before it arrives

If you're heading towards a bill that's much higher than the same time last year, GEM will send you a helpful email to let you know.
Because GEM knows how much electricity you're using, if you have a smart meter, it can predict what your next bill could be long before it arrives.


Get started with GEM


Already with Mercury?

To access GEM, you need to be registered for . If you haven’t already registered, you’ll need your account number (which you’ll find on your Mercury bill), and an email address to sign up.
Once you are registered, just look for the GEM tab within My Account, click on it and start exploring.

It’s that simple.


Not a customer yet?

If you're not a Mercury customer but you're keen to take the guesswork out of your power usage with GEM, you can sign up with us online in less than a minute.

Simply click on the yellow button below to join Mercury online.


Not all GEM features are available to all customers or all types of electricity meters. GEM starts predicting your bill seven days into each billing cycle. Predictions based on historic usage. Your final bill may be lower or higher depending on your actual usage over the period.
PLEASE NOTE: To find out how to upgrade to a smart meter if you don't already have one, simply give us a ring on 0800 10 18 10.