Yes – for most households. Electricity bills can be expected to reduce by 30-60%.
Bill savings and time to recoup investment cost depends on the proportion of power used during the day when your solar panels are generating free electricity.
Shifting power usage to during the day, means investment will be paid back faster, in around 3 years for a typical household. If much of your power is used at night when your panels aren’t generating electricity, payback period will be longer, closer to 5-6 years.