No, this is from averaging it across the entire year, based mostly on locations in the south of Australia (Gippsland, Melbourne, Adelaide, Ballarat, those sorts

No, this is from averaging it across the entire year, based mostly on locations in the south of Australia (Gippsland, Melbourne, Adelaide, Ballarat, those sorts of areas), but I looked briefly at other parts of the world also. The idea is then that a panel rated at 250W can produce an average of about 1kWh per day when pointed in the optimal direction and never shaded (but without tracking the sun); the average winter day may get you only 500W, and the average summer day over 1500W, with plenty of variation within those seasons day by day also.