Estimates how much of a solar system's output a household uses and how much it exports, with and without a battery.
Most of the form is filled in already with figures that give a sensible answer. Adjust what you know and press the button.
Estimate what proportion of a domestic solar PV system's annual output is consumed in the house and what proportion is exported, using the lookup tables in MGD 003.
The tables are not a model. They come from half-hourly monitoring of real British households by Loughborough University, with battery behaviour modelled on top, so they carry the real shape of domestic demand: a peak before the sun is up, another after it has gone, and a quiet middle of the day.
Three things index them. The annual generation, which comes from the MIS 3002 output estimate. The household's annual consumption from a bill based on actual meter readings, which defaults to the British average of 3,500 kWh where it is unknown. And the weekday occupancy pattern, which is 'home_all_day', 'in_half_the_day' or 'out_all_day'; where the pattern is unknown MGD 003 says to use the middle one, and that is what an omitted value resolves to.
Battery capacity is the USABLE capacity, which is smaller than the figure printed on the battery. Supplying import and export prices adds a value in pounds to the result.
Note that self-consumption is not the same as independence from the grid, and the result reports both.
The same calculation answers on
POST /api/calculators/solar-pv-self-consumption
and as the MCP tool solar_pv_self_consumption.
How to call them.
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