What is the output of the panel in terms of kWh?
This varies according to the time of year – in summer we get almost 10times the amount of solar energy that we do in the winter. In the summer, you can expect to get 14kWh of heat per day from a single 20tube panel, whereas in December you can expect only 1.15kWh per day on average. Even in the winter, it is possible to preheat the water to 40C or more if the sun comes out. In fact, if you fit multiple panels, it is possible to heat your hot water to 100C in January (we have seen this in Cornwall).
