Cost Advisor

A Bigger Hot Water Cylinder Can Pay Off

July 16, 2018

The pricing for how electricity is charged in Auckland is changing, and it could mean that having a bigger hot water cylinder will pay off.

The charging system is changing towards time of use (or half hourly) pricing, as well as changes to “peak” and “offpeak” pricing structure, which is defined by the time of day. The difference between peak and non peak charges are substantial, with peak rates being 12.5c/kWh and offpeak at 2.5c/kWh.

The peak rate rate times coincide with the times when hot water cylinders are mostly switched on, which means that people are paying the highest rate for power when they use it the most. With some smart thinking, and larger hot water cylinders, there are ways to minimise this cost and take advantage of the offpeak power rates.

One option that could be looked at is the using a controller to manage when your hot water cylinder is running. This means you could set your cylinder to only switch on at offpeak times. However this would mean that you only have the amount of hot water in the cylinder for use during peak times.

The other alternative is by having a larger hot water cylinder. The theory behind this is that if you have a 135L or a 180L water cylinder which has a typical flow rate of 14L/min, if your shower was at 2/3rds hot this gives you about 15 minutes of hot water stored in your cylinder. At this point the thermostat would be cold and the element would come on to heat the water for the next person. The only problem with this is when you are paying peak rates to do so!

By switching to more storage in the cylinders, the buffer is bigger and therefore means the heating of the water can wait until offpeak to heat, while still having hot water in the tank. This can reduce the cost of water heating by half!

Most larger cylinders are also solar ready which means that you can upgrade to a solar water heating system or a heat pump water heating system at a later date if you decide.

Solar heating  essentially gives you free heat by taking advantage of the free energy from the sun, which is out during peak times, so you will heat your water for free during those periods and if it needs to top up it can do so during off peak hours.

If you decide to go with a heat pump water heating system, you will also save a great deal as their technology is much more efficient than traditional electric water heaters. This means you will spend much less heating the same amount of water as with an electric cylinder.

Both options essentially give you free hot water, and the more you can heat for free, the better!

If you would like to discuss a larger hot water cylinder option for your home, contact us today and we can advise the best options for you!

For finance and payment options




A quote will be sent to you within 30 minutes*



Please provide as many details as possible to simplify the quoting process. If the information you have provided is sufficient, you will be notified within the given times below. If a site visit or any further information is required, our team will advise you accordingly.



*In peak times quotes can take up to 2 hours, larger quotes are subject to free site visits, you will be advised on progress by email.

Success! Your information was sent through.

A team member will be in touch shortly.
Questions? Please call 0800 TEAM EURO