ABOUT

We’ve teamed up with Rinnai NZ to trial new tech designed to optimise how your hot water is heated. With hot water accounting for around 30% of household power use, we'll be studying the impact of smarter heating, to help ease pressure on the national grid.

 

WHAT TO EXPECT

If you’re selected, a small device will be installed next to your hot water cylinder. It connects to a cloud-based platform that learns your household’s usage patterns and schedules heating times according to grid conditions. All while making sure you have hot water when you need it.

The trial will run from 26 June to 31 October 2025. During that time, we’ll ask you to complete a few short surveys to help us better understand your experience. 
  

WHAT’S IN IT FOR YOU?

If you're selected, you’ll receive a total of $250 in account credit — with $100 applied at the start and the remaining $150 if you complete the trial.

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1. REGISTER

Register your interest using the form below. Places on the trial are limited, and we’ll be in touch to let you know if you’ve been selected.

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2. INSTALLATION

If you’re selected, our team will be in touch to arrange an installation in June. A contractor will install the device next to your hot water cylinder — please note, this involves attaching it to the wall with screws. You'll then receive a $100 account credit.

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3. THE TRIAL

The Smart Hot Water trial will run from 26 June to 31 October 2025. During this time, the installed device will optimise your hot water heating in the background. You’ll be able to use your hot water as normal throughout. Once you complete the trial, the remaining $150 account credit will be applied and the device will be removed.

THANKS, REGISTRATIONS FOR THE TRIAL HAVE NOW CLOSED

If you’ve already signed up, we’ll be in touch soon with the next steps. If you have any questions, feel free to get in touch at smarthotwatertrial@mercury.co.nz.

 Together with Rinnai and GridSmart.