Net-metering is set up so that the amount of power you produce offsets the amount of power you use. In an ideal setup, your production would 100% cancel out your usage and, effectively, your utility bill for the year would be $0. Unfortunately, roof space and initial price often dictate system size, so utility bills do not usually completely “zero” out. Therefore, the amount of energy (kWh) you produce each year, times the utility rate that you would have paid for that electricity make up your “Yearly Savings”. Yearly savings will increase as the rate for that electricity increases. Assuming utility rates increase about 5% per year, your yearly savings will roughly double in 15 years, because the electricity cost will be about twice as high as it is now.