Created by Niklas Roy, “Perpetual Energy Wasting Machine” is a rope and pulley mechanism, installed in the staircase of the WRO Art Center in Wroclaw, Poland. The mechanism connects the sliding doors of the elevator in one floor with the elevator call button on another floor. Operating in two directions on the first and on the second floor, the contraption automatically moves the elevator cabin in an infinite loop between those two levels.
Inspired by what Niklas learned at school that energy cannot be wasted – it can only change its location within a system, the projects attempts to address what happens to the energy in this elevator system? Where does it go? The setup is powered by the sliding doors of the elevator. The pulley blocks reduce the sliding door distance of 50 cm to a traveling distance of 12.5 cm for the push button mechanism, while also connecting first and second floor of the building.
The “Perpetual Energy Wasting Machine” moves the elevator in recurring cycles. In the first half cycle, the elevator is lifted up one floor, while the latter half cycle brings the elevator down to its original position again. As this is an hydraulic elevator, and as the cabin´s mass is not equalized by a counterweight, only the movement up consumes electricity. Estimating that the empty elevator cabin has a mass of 350 Kilograms, the wasted energy is about 11.8 Kilojoules per cycle (which equals to the metabolic energy of ca. 1/3 grams of fat, according to Wolfram Alpha ). A modified printing calculator inside the elevator cabin keeps track of the wasted energy, automatically adding up 5.9 Kilojoules for each half cycle. The results of this symbolic calculation – which does neither regard energy loss by friction, nor a heavier cabin due to possible passengers – go straight to a waste bin, located beneath the printing calculator.
The hardware in the staircase includes only ropes and pulleys. Inside the elevator, there is a printing calculator which is controlled by an ATmega8 via a relay board, programmed in AVR-GCC. The relay board basically ‘pushes’ the buttons of the calculator, performing the calculation “5.9+=” seven seconds after the door has closed.