Elevator Energy Cost Calculator

Car Weight has no effect on Annual Energy Cost, Peak Motor Power, or any other cost or consumption output on this page -- despite appearing directly in the motor-power formula. This is not a bug; it's how a correctly counterweighted elevator is supposed to behave. The counterweight is modeled as Car Weight plus 45% of Rated Load, and the motor only has to overcome the imbalance between the car-plus-passengers side and the counterweight side of the hoist cable. Algebraically, Car Weight appears on both sides of that imbalance and cancels out completely, leaving the net mass the motor must move as a function of Rated Load alone (about 2% of Rated Load on the up trip, roughly 32% on the down trip, using this calculator's assumed 43%-loaded average trip and 45%-of-load counterweight offset). That is the entire point of a counterweight system: a heavier car gets a proportionally heavier counterweight, so the drive is sized to the passenger load imbalance, not the car's own mass.

Electricity Rate has the largest measured effect on Annual Energy Cost across most of this calculator's input range, and that is close to mathematically guaranteed -- Annual Energy Cost is Annual Consumption multiplied by Electricity Rate with nothing else standing between them, so a given percentage change in rate always produces exactly the same percentage change in cost. Every other input acts through the nonlinear motor-power and standby-time chain instead, which dilutes its effect below that ceiling in most regimes -- but not all: Annual Energy Cost always has the structure (a term inversely proportional to Drive Efficiency, from trip/motor energy) plus (a term that does not depend on Drive Efficiency at all, from standby energy), so it is never purely linear in Drive Efficiency anywhere in the range. At very tall installations (Total Travel Height at or above 450 m at this calculator's other defaults), Standby Power's daily contribution is driven all the way to zero, and beyond that point Annual Energy Cost becomes exactly (not just approximately) inversely proportional to Drive Efficiency, with no remaining constant term. That reciprocal relationship responds slightly more than proportionally to an equal-sized nudge, which lets Drive Efficiency's measured effect edge past Electricity Rate's fixed ceiling toward the tallest end of the declared range (still trailing it at 400 m, roughly matching it around 450-500 m, and edging ahead by 600 m). Regeneration only discounts descent energy, so it never fully offsets the trip energy the ascent leg consumes.