Weather

Related Damage

Gas Turbine Engine Failure

Weather Related Damage

Gas Turbine Engine Failure

Weather Related Damage

Gas Turbine Engine Failure

A 50-megawatt natural gas turbine generator failed when freeze damage to the inlet-air cooling coils allowed water to flow into the turbine while it was running.  The generator was part of new a central utility plant at a federal government campus in the Washington, D.C. area.  The construction project was nearing completion at the time of the incident.  There were numerous contractors and subcontractors working with the generator and related systems at the time of the incident.  The EIS engineer assigned to the project was tasked with determining the role weather had in the failure, as well as understanding if the involved parties exercised due care in operating the subject equipment.

Natural Gas Turbine Genrator

Inlet-air cooling coils are used to reduce the temperature of the combustion air entering a turbine.  Reducing the inlet-air temperature can increase the efficiency of a turbine during the warmer months of the year, but is not necessary in the winter months when outdoor temperatures are already low.

Review of the documented operational procedures for the turbine revealed that the inlet-air cooling coils were supposed to have been drained and winterized prior to the onset of freezing temperatures.  Project documentation showed that winterization of the coils was performed in the Fall, prior to the first forecasted freezing temperatures. 

The building management system (BMS) used to control the turbine and other related systems was equipped with numerous control points and sensors that recorded data which was stored in the BMS computer system.  The recorded data showed that, subsequent to the winterization of the turbine, there were two additional cold spells wherein the temperature of the air entering the turbine was sub-freezing. 

The condensate that drains from the inlet-air cooling coils during summer operation was piped to a collection tank that was equipped with a float sensor used to record the level of water in the tank.  Review of the BMS data for the tank level showed that there was an increase in water level during a warm period that followed the second of the two periods of sub-freezing temperatures.  It was believed that water left in the inlet-air coils froze during the second period of freezing temperatures and cracked the coil tubes.  When temperatures began to rise, the coils thawed, and the water leaked from the coils and drained into the condensate collection tank.        

Broken Coil Bend

Review of the daily project work logs in the days between the first and second periods of sub-freezing temperatures revealed which parties were working on the inlet-air cooling coils.  It was determined that in the days prior to the coils freezing, they were refilled with water so that testing could be performed.  However, the coils were not re-winterized.  Damage to the coils went undetected until months later when outdoor temperatures rose, and system operators attempted to fill the coils.  Water entering the coils drained through cracks in the damaged coils and entered the turbine, causing it to fail.   

Damaged Turbine Blade

A 50-megawatt natural gas turbine generator failed when freeze damage to the inlet-air cooling coils allowed water to flow into the turbine while it was running.  The generator was part of a new central utility plant at a federal government campus in the Washington, D.C. area.  The construction project was nearing completion at the time of the incident.  There were numerous contractors and subcontractors working with the generator and related systems at the time of the incident.  The EIS engineer assigned to the project was tasked with determining the role weather had in the failure, as well as understanding if the involved parties exercised due care in operating the subject equipment.

Natural Gas Turbine Genrator

Inlet-air cooling coils are used to reduce the temperature of the combustion air entering a turbine.  Reducing the inlet-air temperature can increase the efficiency of a turbine during the warmer months of the year, but are not necessary in the winter months when outdoor temperatures are already low.

Review of the documented operational procedures for the turbine revealed that the inlet-air cooling coils were supposed to have been drained and winterized prior to the onset of freezing temperatures.  Project documentation showed that winterization of the coils was performed in the Fall, prior to the first forecasted freezing temperatures. 

The building management system (BMS) used to control the turbine and other related systems was equipped with numerous control points and sensors that recorded data which was stored in the BMS computer system.  The recorded data showed that, subsequent to the winterization of the turbine, there were two additional cold spells wherein the temperature of the air entering the turbine was sub-freezing. 

The condensate that drains from the inlet-air cooling coils during summer operation was piped to a collection tank that was equipped with a float sensor used to record the level of water in the tank.  Review of the BMS data for the tank level showed that there was an increase in water level during a warm period that followed the second of the two periods of sub-freezing temperatures.  It was believed that water left in the inlet-air coils froze during the second period of freezing temperatures and cracked the coil tubes.  When temperatures began to rise, the coils thawed, and the water leaked from the coils and drained into the condensate collection tank.        

Broken Coil Bend

Review of the daily project work logs in the days between the first and second periods of sub-freezing temperatures revealed which parties were working on the inlet-air cooling coils.  It was determined that in the days prior to the coils freezing, they were refilled with water so that testing could be performed.  However, the coils were not re-winterized.  Damage to the coils went undetected until months later when outdoor temperatures rose, and system operators attempted to fill the coils.  Water entering the coils drained through cracks in the damaged coils and entered the turbine, causing it to fail.   

Damaged Turbine Blade

A 50-megawatt natural gas turbine generator failed when freeze damage to the inlet-air cooling coils allowed water to flow into the turbine while it was running.  The generator was part of a new central utility plant at a federal government campus in the Washington, D.C. area.  The construction project was nearing completion at the time of the incident.  There were numerous contractors and subcontractors working with the generator and related systems at the time of the incident.  The EIS engineer assigned to the project was tasked with determining the role weather had in the failure, as well as understanding if the involved parties exercised due care in operating the subject equipment.

Natural Gas Turbine Genrator

Inlet-air cooling coils are used to reduce the temperature of the combustion air entering a turbine.  Reducing the inlet-air temperature can increase the efficiency of a turbine during the warmer months of the year, but are not necessary in the winter months when outdoor temperatures are already low.

Review of the documented operational procedures for the turbine revealed that the inlet-air cooling coils were supposed to have been drained and winterized prior to the onset of freezing temperatures.  Project documentation showed that winterization of the coils was performed in the Fall, prior to the first forecasted freezing temperatures. 

The building management system (BMS) used to control the turbine and other related systems was equipped with numerous control points and sensors that recorded data which was stored in the BMS computer system.  The recorded data showed that, subsequent to the winterization of the turbine, there were two additional cold spells wherein the temperature of the air entering the turbine was sub-freezing. 

The condensate that drains from the inlet-air cooling coils during summer operation was piped to a collection tank that was equipped with a float sensor used to record the level of water in the tank.  Review of the BMS data for the tank level showed that there was an increase in water level during a warm period that followed the second of the two periods of sub-freezing temperatures.  It was believed that water left in the inlet-air coils froze during the second period of freezing temperatures and cracked the coil tubes.  When temperatures began to rise, the coils thawed, and the water leaked from the coils and drained into the condensate collection tank.        

Broken Coil Bend

Review of the daily project work logs in the days between the first and second periods of sub-freezing temperatures revealed which parties were working on the inlet-air cooling coils.  It was determined that in the days prior to the coils freezing, they were refilled with water so that testing could be performed.  However, the coils were not re-winterized.  Damage to the coils went undetected until months later when outdoor temperatures rose, and system operators attempted to fill the coils.  Water entering the coils drained through cracks in the damaged coils and entered the turbine, causing it to fail.   

Damaged Turbine Blade