Household Savings Calculator

Just fill out the form then click the big green button to calculate your nominal savings with Showerex.

We have pre-selected typical values for a New Zealand household to get you started.

For businesses, use our commercial savings calculator.


Nominal Calculation Details

Calculation is based on an average shower with a mixed shower temperature of 38°C, hot water cylinder temperature of 60°C, cold water temperature of 11°C for horizontal installation and 11.5°C for vertical installation, specific heat of water of 4.186 joules per °C per gram, and does not account for any change in flow caused by temperature limiting valve. Calculation also excludes any savings made in the period before a shower when shower and Showerex is warming up.

CO2 saved is calculated based on the average CO2 emissions per kWh of electricity generated in New Zealand (0.1287 kg per kWh) as reported by the New Zealand Government's EECA Business CO2 Emission Calculator on 8th May 2019.

Return on investment and payback period are calculated based on a purchase price of $657.80 for Showerex 900 and $736.00 for Showerex 1400, which includes New Zealand GST and freight but excludes any installation costs.

For additional information see the Showerex Calculator Technical Explanation PDF and the Showerex CO2 Savings and Embodied CO2 PDF.

New Zealand Domestic Electricity Prices

In most parts of New Zealand consumers pay much more for their electricity than the default $0.30 per kWh used in the calculator. If you live in one of these areas your savings with Showerex will be even greater.

Check your last power bill to find the rate you pay or find as estimate based on the rates provided by the New Zealand Government Ministry of Business, Innovation, and Employment in the following chart:

Calculate How Much You'll Save
New Zealand Green Building Council Member
New Zealand Green Building Council Member