If you think I’m mistaken, you may be thinking of a solar powered calculator, which is an entirely different thing. No, I’m not referring to a solar calculator where you never need to change the batteries I am talking about a solar power savings calculator to help you work out the most important issues about switching to a solar energy system: keeping down the cost and working out how much you can save.
By the time I got around to building my second solar power system, there were plenty of solar power cost calculators in existence, but no solar power calculator for Australia. The vast majority had been developed for the American market, and a few for Europe.
Then suddenly one day… whoosh!… there I had the answer in a flash of inspiration! There’s absolutely no need at all to go high-tech. All you need is one of those fancy erasable whiteboards, or even an old school chalkboard will do. Grab one of those and draw up a grid on it with 2 rows and 10 columns.
In the 2nd row of the left column, just jot down the power rating, e.g. 5kW. Across the top row, starting from the 2nd column, write these headings:
- Controller $
- Inverter $
Work out what kind of panels and batteries you are after, and then get on the blower to your local installer. Ask how many panels of your chosen type are needed for a system of each size on your chart. Then ask the cost per panel. Then ask about the batteries and so on.
Then all you have to do is multiply the number of panels by the cost per panel and write that in the first blank column. Then multiply the number of batteries by the cost per battery and write that in the second blank column. Now just add the total of those two columns to the cost of the controller and inverter for that type of system and write the answer in the TOTAL column.