Their bills contain other mysterious figures as well. For example, when a developer completes construction of a commercial high-rise, it estimates the building's electricity consumption and enters into a contract with TaiPower on that basis. TaiPower then assigns the building a "contract volume," effectively a monthly quota, and calculates a monthly "power factor."
以商辦大樓來說，建商將大樓蓋好時，就會預估將來的使用電量而和台電簽好契約，台電會給一個「契約容量數」和「功率因數」，譬如契約容量為 450 千瓦，功率因數 95 %（指台電供給 100 % 的電力，用戶端的使用效能可達到 95 %）。