Final answer:
The information provided states that, according to the default values on NREL's PVWATTS website, a south-facing photovoltaic (PV) array with a tilt of 40 degrees in Boulder, CO, is predicted to receive 5.42 kWh/m2/d of insolation.
Step-by-step explanation:
The subject of this question is Physics. The question involves calculations related to solar energy and photovoltaic (PV) installations.
It requires converting insolation values from kWh/m²/day to W/m², understanding the relationship between insolation and AC energy produced by PV modules, and determining the appropriate size of a residential PV installation based on required energy production and site insolation.