Enphase dashboard for our first month of solar:
The blue bars represent energy produced by the solar panels. The orange bars represent energy consumed by us. The Y axis is kilowatt-hours (pay attention to the Y axis, because the dashboard rescales it).
According to the numbers above, the solar panels generated 78% (1 - 117.4/538.6 = ~0.78) of our consumed energy for the month. Virginia has net metering, so our power bill should be 21% of what it would be otherwise.
On clear, sunny days the panels generate more energy than we consume:
And in a shocking twist that will surprise no one, on cloudy days the solar panels don’t do very well: