Average monthly electricity account $
Annual power account $
Percentage of power bill hot water accounts for   %
Hot water rate (cents per kWh)   c
Standard electricity rate (cents per kWh)   c
Cost of Mirak solar hot water system   $
Average Monthly savings    
Payback time is   years
Enter current mortgage interest rate %
Enter current mortgage principal   $
Payback time (Including savings from reduced interest payments)   years



1) Enter the average dollar cost of your monthly or annual electricity account. (Do not include line charges). Your average  electricity account information can be obtained from your power account or from your supply company.

2)Typical hot water use accounts for 45% of your electricity account. This will vary.

3) If you are on a flat rate for your electricity, ie no night rate, then enter the same figure into both the standard and hot water rate boxes.

4) Price information can be found in the products section.

5) Click the 'Submit' to view projected monthly savings and payback time.

6) The optional mortgage calculation applies if you have a revolving credit mortgage. Please select the tick box if you want to use this option.

7) The mortgage calculation reduces your principal by the 'average monthly saving'. The interest you save from reducing your principal is added to your 'average monthly savings'. The new payback time is calculated from this amount.

8) The mortgage calculation includes putting the system cost on your mortgage. No fees have been allowed for.

DISCLAIMER: The information generated by this calculator is an estimate only. Actual performance will vary depending on individual installations.