300% ROI on Green Practices

[Adrienne Selko]

STMicroelectronics is one of the top semiconductor makers in the world. Maybe they rose to that status based on good business practices given that their “green” initiatives have resulted in a 300% net ROI.

Since 2001 they have invested $229 million and have seen $1.2 billion in total savings and $993 million in net savings. Those are numbers we’d all like to report.

Their green journey began back in 1994 with the declaration of their 10 Commandments of Going Green. Looking at their numbers they can certainly declare success.

•The company reduced its CO2 emissions by over 61% since 1994, with a pledge to be renewable energies neutral by 2010

•From 1995 through 2006, ST reduced its energy consumption by 5.3% per year and its water consumption by 9% per year --the equivalent of a 250-megawatt power station saved, and enough water to quench the thirsts of Italy and France combined.

•By using the cooling power of the environment (i.e. cold air) at some of its plants, ST was able to turn off the refrigeration units for up to 6 months a year for an annual reduction of 5,400 tons of CO2 emissions and substantial reduction in electricity costs.

•At some of its plants, ST saved energy, money and reduced CO2 emissions by continuously cleaning heat exchanger tubes. The tubes would become clogged after a few weeks, cutting down on peak operating efficiency. By forcing small rubber balls down the cooling tubes once a month, ST kept them open and operating at peak efficiency, saving power (6 to 15 gigawatts), money ($475,000) and reducing CO2 emissions there by 3,300 tons—annually.



Scale deposit on condenser tubes reduces the heat transfer efficiency of chillers and increases energy consumption. By means of the Ball Technic System (BTS) TM, a fully automated condenser cleaning system circulates slightly oversized sponge balls to scour off all scales and fouling. AT ST's Toa Payoh site in Singapore, this resulted in chiller energy consumption reduction by an average of 20%, or 170 MWh hours per month, with savings of K$ 120 per year.


STMicroelectronics, a top producer of application-specific analog chips and power conversion devices, is comprised of 15 main manufacturing sites, 16 advanced research and development units and 39 design and application centers.