PV surplus
PV surplus in the SpeicherCampus context: an important storage potential. Technically, the term is usually described as PV generation above current consumption.
What does PV surplus mean?
PV surplus is the part of solar generation that exceeds current consumption. Without storage it flows to the grid — remunerated at rates usually far below the purchase price — or is simply curtailed under feed-in limitation.
For storage planning, the surplus is the resource: its daily amount determines how much capacity can be filled each day, and its time profile defines the charging window.
What matters in practice
- calculate the surplus from PV simulation and load profile at quarter-hour resolution
- mind the summer/winter spread: winter surplus is often a fraction
- the spread between feed-in rate and purchase price determines its value
- growing self-consumption (e-mobility!) eats into the surplus over the years
Practical example
A 100 kWp system generates 180 kWh of daily surplus in June but only 15 kWh in December. The storage was sized for the spring/autumn value of 90 kWh — the summer peak splits between battery and export, and winter remains grid operation.
The SpeicherCampus perspective
SpeicherCampus never estimates PV surplus with a rule of thumb, but calculates it from the real quarter-hour data of both curves — generation and load.