Competitive thanks to industrial power generation

Combined heat and power

The Mexican textile firm Grupo Kaltex needed to lower costs to compete better against cheap foreign imports. Encouraged by the government to be energy independent, it chose a Siemens SGT-750 cogeneration plant to produce its own electricity and steam, with a prospective return on investment in just four years.

In business as in life, timing is everything. At the same time Mexican textile manufacturer Grupo Kaltex was reaching a critical need to reduce energy and steam costs at several plants where it makes fibers and fabrics, Siemens was about to begin production of a highly efficient addition to its line of industrial gas turbines, the SGT-750.

Coincidentally, the Mexican government was ending its monopoly of electric power, and offering attractive incentives to large companies like Grupo Kaltex to build their own power plants, and produce their own electricity onsite in an environmentally friendly way. These factors convinced Kaltex that the relatively compact Siemens SGT-750 would be the perfect means of supplying low-cost power and vapor to its plant in northern Tamaulipas state. The decision is already producing handsome dividends for the 91-year-old company.

Steam is an essential input for manufacturing synthetic threads, denim fabric, and other products. The cogeneration plant produces both electricity and vapor.

Sound investment
Today, the new SGT-750 cogeneration plant is producing 32 megawatt-hours of electric energy, approximately 40 percent of the total power consumed at Kaltex’ cluster of plants in and around Altamira, and sending 54 tons of steam daily to its manufacturing processes.

Power plant manager Julio Correa estimates that his company’s energy costs are down about 30 percent since the SGT-750 became fully operational and that the investment, which included Siemens engineering, HRSG, and electrical and controls hardware, could pay for itself in four years.

These cost savings come at a critical time for Grupo Kaltex, a company that has about 18,000 employees in North, Central, and South America and is one of Latin America’s largest textile concerns. Like all firms in its sector, Kaltex is under siege in its markets from low-cost Asian imports. With controlling costs and securing supply, an absolute Kaltex imperative, the SGT-750 has helped it take a giant step forward in maximizing efficiency.

Now, Kaltex can rely on the electric supply to its manufacturing processes and, as a consequence, improve quality and reduce waste.

Julio Correa, power plant manager at Grupo Kaltex

The energy efficiency comes from the cogeneration engineering, which enables Grupo Kaltex to avoid having to buy energy separately to produce steam, an essential input for manufacturing acrylic fibers at its Altamira site. How? The Siemens combined heat and power system makes the steam itself, with a boiler powered from heat produced by the turbine as it generates electricity.

“When you have a cogeneration plant, you only buy gas to produce the energy,” said Correa. “It is this additional production of vapor that makes this part of the cycle much more efficient. This allows us to offer products at a more competitive cost.”

Reliability improves
Improved reliability is another benefit accruing to Kaltex for having its own power plant. Prior to the installation of the SGT-750, the company suffered repeated power outages. That caused process interruptions, lower productivity, and problems in quality control.

“Now, Kaltex can guarantee the reliability of electric supply to its manufacturing processes and, as a consequence, improve quality and reduce waste,” Correa said, adding that the SGT-750 system is fueled with low-cost natural gas, much of it coming via pipeline from the USA.

“This cogeneration plant is user-friendly,” Correa says. “It practically talks to us!”

Environmentally friendly
Being a good corporate citizen by reducing its carbon footprint with its SGT-750 has produced an added benefit for Grupo Kaltex. Since the system was installed, the company received a special “efficient cogeneration” certification from the Mexican government. The distinction is not only an environmental badge of honor. It qualifies the company for lower power-transmission costs as well as price supports in times of general power emergencies, Correa said.

Why did Grupo Kaltex choose Siemens for this critical acquisition? The company’s reputation for leading-edge engineering and technology was a big reason, as was its commitment to “accompany” Kaltex as it ramped up the SGT-750 to full operation and trained a corps of engineers to manage it. Correa also highlighted the system’s automatic controls that flag operators in advance of possible problems and his twice-monthly conference calls with Siemens engineers in Europe.

“This cogeneration plant is user friendly,” Correa said. “It practically talks to us, sends messages if something is bothering it so that operators can interpret them and respond to any problems it might have. That ability to anticipate situations gives us a high degree of confidence.”