Industry's First Uninterruptible Power Supply Energy Saving Mode

All facility systems and process equipment are equipped with uninterruptible power systems to manage fluctuations in power. However, in order to protect against power dips, UPS systems must be charged 24 hours a day through the rectifier to store energy, and then through the inverter to supply power. This causes additional energy consumption 5% above normal operations. To reduce energy consumption, TSMC collaborated with UPS suppliers to develop a UPS energy saving mode to provide more energy saving measures for the industry and increase energy efficiency.

Power Dip Analysis and Firmware Improvement

TSMC and vendors analyzed UPS records for all power dips from 2015 to 2016, reviewed the relationship between parameter sensitivity and power dip protection actions one by one, and consulted power experts on internal firmware logic to optimize UPS and find a safe energy-saving mode.

Precise Verification, Reliability 100%

If facility operates abnormally, fabs will suffer significant operational loss. Therefore before the full implementation of new energy saving project, we introduce a 116-items verification through a third-party of international verification authority (Underwriters Laboratories Inc.). It ensures that when power supply is abnormal, the action logic of new energy saving mode conforms to the international semiconductor industry voltage transient strain ability specification (IEEE SEMI F47). Additional load tightening tests are also applied. The new energy saving project is fully implemented only after three times of 100% power dips reliability confirmation.

Improving Efficiency, Creating a Win-win Situation

Under the newly-designed UPS energy-saving mode, power is normally supplied via an energy saving path (as shown below), and the UPS can instantly switch to voltage compensation to protect production tools when voltage is abnormal. The UPS not only reduces energy consumption by 5% but also increases efficiency from 94% to 99%. In 2016, this energy saving measure was introduced to advanced technology production successfully which saved 14.4 GWh, accounting for 16% of the company's annual energy savings. It is a major breakthrough in factory power conservation.