Hot Water Control

When you call, your Retailer will take you through a quick check list to find out whether the problem is inside your home or outside, on the electricity network. Here’s what you can do to help:

• Ask if your neighbours have power – if a number of houses in your neighbourhood are without power or hot water, it’s likely to be a network problem and part of a wider power cut. In this case, you can check our current outages to see if your area is affected by a Horizon Networks outage, or report a problem in your area.
• Check the main switchboard in your home– you may have blown a fuse. Did the power fault happen just after you turned on an appliance in your home? If the answer is yes, this could be a fuse problem.

Horizon Networks controls the hot water heaters connected to our network from the start of May to the end of September. This means hot water cylinders are likely to be turned off on cold days typically between the hours of 7:30 to 9:30 am and/or 17:30 to 20:30 pm. Following a load control period it may take some time for your hot water cylinder to reach its normal operating temperature and, if you use a lot of hot water during that time, you may run out of hot water.

Turning off the hot water heating during peak times helps reduce the amount of peak electricity being used in the Lower North Island. Hot water can be heated at non-peak times rather than during the peak when households need electricity for heating and cooking. Essentially, it's a simple, effective way of flattening out the peaks and troughs of demand for electricity.

This control reduces congestion on the National Grid and avoids bringing forward costly new grid investment just to meet periods of peak demand. By managing the peak demand on the Horizon Networks network, National Grid transmission charges can be reduced and these savings are passed on in full to our customers through reduced charges. If load control was not done it, household bills could rise by over $200 per year.

A typical hot water cylinder will retain its temperature over the period we load control provided it is at operating temperature and there is limited hot water usage over the period of control. By understanding the typical periods of load control and reducing hot water consumption before, during or immediately after a load control period the cylinder will take less time to return to its normal operating temperature.

Other measures that can be taken include reducing the heat loss from your hot water cylinder (using a cylinder wrap) and or setting your cylinder's temperature to 60°C or above (the temperature recommended to prevent legionella) which can extend how long the hot water will last for versus those set at a lower temperature. (Caution: Do not raise the temperature above 60°C unless you have a temperature limiting valve on the outlet to the cylinder to prevent scalding). Like to learn other ways to save on hot water? Check out this article.