Customer Testimonial - Q-Dot Air Pre-Heater Replacement

In 2023, U.S.-based independent power producer Schuylkill Energy Resources (SER) approached Econotherm to replace a Q-Dot heat pipe air per-heater at its 80-MW St. Nicholas Electric Power Generation Station in Shenandoah, Pennsylvania, U.S. Performance of the unit, which had been in operation since 1987, had degraded over time due to several known issues, including pipe corrosion, leakage and degradation of the organic working fluids.

In 2024, new heat pipe modules were shipped from Econotherm's facility in Wales, UK, to the St. Nicholas station, where they were installed during a scheduled shutdown.

Fast-forward to September 2025, and we received this feedback from Alexander Brush, General Manager of Gilberton Power & Schuylkill Energy:

"Econotherm Ltd. was selected to reverse engineer and retrofit a replacement unit for our boiler’s Q-Dot Air Pre-Heater. The team handled the project with the utmost professionalism and flexibility. All delivery milestones were met on time or ahead.  From their engineering and design team, to their technical workers, to their sales and support staff, the whole organization sets the standard for large-scale industrial project management. Not only did they exceed our expectations from a design, manufacturing, and delivery standpoint, but more importantly, the unit outperformed best-case expectations by almost 7%, resulting in decreased fuel consumption, improved pressure part wear, and ultimately a much improved revenue position and payback period.  Our companies’ plants are almost certain to engage their expertise again in the future."

Inside the Q-Dot heat pipe air pre-heater shows that, prior to its repair, many of the heat pipes had been removed due to breakages and corrosion.

The new heat pipes, manufactured in Wales, were based on a more robust stainless-steel pipe design that reduced fouling and simplified cleaning procedures. 

Interested in learning more about this installation? Email jamie.zachary@solexthermal.com to receive a detailed case study that provides initial findings, before/after process data and results.