Solar Power Calculator

This step-by-step Solar Power Calculator offers a guideline for typical appliance ratings and sizing of solar systems.

OPEN or DOWNLOAD the Excel spreadsheet.

Only enter data into the PALE ORANGE columns. Insert all figures in decimal, eg 2 or 1.5.

If your items are not listed on the form, select the nearest item available from the list. The list of appliances with power ratings is a guideline only. The power ratings are average ratings and vary from supplier to supplier.

Sinetech advises that the user first look at all the appliance rating plates they wish to run on solar power (which is usually fixed at the rear or bottom panel of the appliance) or at the manual to obtain the correct “Watt rating”. If you only find Amp. Ratings, use the following formula: V x A = W. For example, the value you find is indicated at 2.5A. 2.5A x 230Volts = 575 Watts. That means that the appliance is using 575 Watters per hour (1kW = 1000W).

If you cannot obtain any values, use the value in the central columun “Average Watts column.

If any rating on your equipment is in VA (Volt / Amps) insert the VA value.

You may also wish to complete this general enquiry form to begin the process of designing and costing a system to suit your needs:


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