Savings so far

People can get very hung up on trying to calculate their "Return on Investment" and it is easy to get into a protracted discussion about how much a system is saving. I am using two measures:

Since installation, my electricity bill this year has reduced by 68.0% compared to last year. This includes ALL savings: tariff change, time-shifting, solar used, export payments. The same metric can be presented as "The bill has been reduced to about 32% of what it was".

Since installation, solar energy has subsidised 57.0% of the cost of our electricity (direct solar consumption, consumption via the battery and export payments combined). Another way of presenting the same metric is: "I pay for only about 43% of the electricity used".

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