Balancing activities
A balancing activity changes in the opposite direction to a primary activity. This models electrification: petrol kilometres decrease, and electric kilometres increase.
The transfer rule
Balancing change equals minus primary change, multiplied by a multiplier.
A heat pump multiplier of 0.25 means four units of useful heat from one unit of electricity.
When the primary activity reaches zero, the balancing activity stops changing. This prevents negative petrol use while electric use keeps growing.
An internal action can use two balancing activities. Example: a plug-in hybrid reduces diesel and increases electricity and petrol.
Different units need an explicit conversion factor. Example: gigajoules of gas to kilowatt-hours of electricity.
Example: reduce petrol kilometres
Start at 10,000 petrol kilometres. Reduce the primary activity. The balancing activity rises by the multiplier.
If a needed balancing row is missing, the engine can insert it at zero. Review that row on Activity Data and save it. Related: FERA / well-to-tank.