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Project Updates

October 9, 2019

Dear neighbor,

We have received calls and emails regarding the commissioning activities of the AES Huntington Beach Energy Project (HBEP). We hear you and want you to know that we take your concerns very seriously.

As you know, the first unit of the AES HBEP was started up for the first-time last week after over 2 years of construction. During this process, natural gas is combusted in the gas turbines to produce high pressure steam which is then used to clean the main lines/pipes of the HBEP. This is the Steam Blow phase of the commissioning process. This phase is critical for avoiding damage to the equipment and the life of the plant. The heat and steam pressure will ensure that the newly installed steam system is perfectly clean, ensure no foreign material can get into the steam turbine and the plant systems are functioning properly.


The Steam Blow phase can last anywhere from about one to two weeks. During this time, steam blows may occur 24-hours per day in a close-loop cycle. In addition, open air Steam Blows will occur intermittently between the hours of 8 a.m. and 6 p.m. During the open-air Steam Blows, steam is released from the steam lines and vented to the atmosphere. This creates a large steam plume and is louder than the close-loop cycle blows. A loud hissing sound will be heard during open air Steam Blows, however, both close-loop and open blow Steam Blows will create some noise.

This is temporary and will not be a part of normal operations. We are trying to get through this process as quickly and as safely as possible.

Yellow/Light Orange Plume

We have also received calls regarding the yellow/light orange plume vented from the new stack, and this too is also a normal part of the commissioning process. What you are seeing is oxides of nitrogen. This happens for two reasons; 1) pollution control equipment cannot yet be installed on the new units which results in higher oxides of nitrogen than what we would get during normal operations, and 2) the turbine is running at much lower rate than normal operations. The pollution control equipment will be installed as soon as the steam blow phase has been successfully completed and further commissioning operations should not reveal a yellow/light orange plume. These emissions were assessed during the permitting phase and the result is that maximum possible impacts are less than air quality standards. This is temporary and will not be a part of normal operations. Like the steam blow phase, this will be resolved in one to two weeks.

Where are we at now?

The first of two units has successfully completed the Steam Blow phase. The second unit will initiate first fire soon. When the second unit successfully completes the Steam Blow phase, both units will run through a Steam Blow phase together. This will complete the Steam Blow process and will begin the Steam Blow Restoration Period. The steam plume from the initial first fire and steam blow may have a yellow/light orange appearance at first. There may also be an odor emitted from this initial process. Should this occur, it will usually clear itself in a short time.

I want to reiterate that this is temporary and will not be a part of normal operations. On behalf of myself and the AES team, we hope you will bear with us and truly appreciate your patience.


The AES Team
(888) 372-5633

August 30, 2019


We are now about 95% complete with construction of the Huntington Beach Energy Project (HBEP) and preparing for the next phase of the project, commissioning and start-up activities.

In the commissioning phase all critical systems and components of the new plant, from high-voltage electrical systems to pumps, fans and compressors will be tested and 'commissioned' to insure they meet their design specifications and can operate safely and effectively. Cold commissioning, which has been going on since January, ensures that all equipment is fitted, connected and operating correctly within the HBEP. Hot commissioning is the first start up and testing of the plant with fuel (natural gas). This will be the 'first fire' of the new plant, the first time that natural gas is combusted in the gas turbines and the first time steam is produced to clean and test the entire steam system in the plant. Hot commissioning of the HBEP will include, first fire of the gas turbines, Steam Blows, Steam Purity Run, and the Initial Steam Turbine Run before the final performance testing of the entire plant.

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To learn more about commissioning and start-up activities, click here for the More Info page, where you will find the HBEP Commissioning and Start-Up Activities Frequently Asked Questions (FAQ).


Dalia Gomez
AES Community and Public Affairs Manager

Construction Timeline