Why would NAES Corp, the largest third-party O&M services provider to combined-cycle facilities, run a three-day conference on NERC-related issues and compliance for its people and select clients and industry stakeholders? For one thing, NAES has 130 plants under its purview and supports over 100 plants outside its portfolio.
Then you might ask: Why does NAES have over 20 subject-matter experts (SMEs) in its NERC Compliance Services Group, which also includes a Compliance Testing arm? The answer: Managing NERC compliance risks for clients is a business in itself, and a key area of growth for the company. It is also considered a competitive distinction by NAES executives.
As one presenter, from a major ISO, put it, “the operations staff does not have the desire, or time, to review or interpret regulatory requirements in real time.” Put another way by another presenter, CIP (critical infrastructure protection) standards are now too complicated for the typical plant employee; many asset managers simply don’t have the experience or the background to manage NERC compliance risks.
A NAES NERC services group leader added, “NERC now has to be taken into account for any project, big or small, that has potential to impact facility output.” Scenarios he gave as examples include engine (GT) tuning, for which he listed six impacts of NERC standards; relay upgrades, which touch at least four NERC standards; and excitation control upgrades, which touch at least seven standards.
While the depth and breadth of the material presented was, well, almost overwhelming, much of it of most interest to combined-cycle owner/operators centered on EOP-011-2, recently adopted by NERC (but still in draft) addressing emergency operations and preparedness generally, and cold-weather readiness in particular.
One presenter suggested that valid bids into ISOs will be required to submit new weather-related data, such as minimum design temperatures, historical operating temperatures, and current cold-weather performance temperatures as determined by engineering analysis. EOP-011-2 includes deadlines and procedures for cold-weather preparation plans, identifying and tasking a responsible coordinator, definition of the “cold-weather period,” assessment of winter readiness, and new monitoring requirements for detecting failures, especially in heat-trace systems.
Update: There is now a Standard Authorization Request (SAR), entitled “Extreme Cold Weather Grid Operations, Preparedness, and Coordination” (Oct 6, 2021), that would add some additional requirements to EOP-011. These would include requiring annual training for generator owners and operators, detailed root-cause analyses for any freeze-related failures, and retrofit of existing generating units to operate in “extreme” weather conditions for their locations.
As one concrete impact, additional operator rounds will be required when ambient temperatures fall below certain limits, such as rounds once per shift when temperature falls below 32F, two rounds per shift when below 20F, and so on. Anything that could initiate an automatic trip should be included on these rounds. Training in cold-weather operations will have to be provided to site staff.
Reflecting, one highly experienced industry engineer advised that temperature is only part of the equation. Wind direction and velocity also are meaningful factors, he said, as are duration and current plant state (running, offline, etc). He recalled working at a facility that could run/start/operate at -20F when there was no wind. But when there was a 20-mph wind from the West it struggled at +20F. After five years of operation, staff was still ill at ease when confronted with uncommon temperature and wind combinations.
One of the presentations provided some instructive real-world cold-weather horror stories, including these:
- A 2 × 1 combined cycle in Nevada, designed with a 15F heat-trace system, experienced 7F ambient. The GT inlet bleed valves started behaving erratically, and operators were cycling through fans to keep the air-cooled condenser operating. When the cold-reheat pressure transmitter froze, it tripped the plant. One week later, the plant was able to restart.
- A 2 × 1 plant in Washington state suffered a cold snap and heavy snow. Natural-gas demand in the area overwhelmed supply lines. Ice and icicles formed. The fuel-gas system alarmed on low pressure. When the third fuel regulation station failed to operate, the unit tripped. Moisture trapped in piping froze.
- At a third facility, $100,000 worth of transmitters had to be replaced after a cold-weather event; water buildup in low points of oil feed pipes froze, and ice built up on the cooling towers because they lacked drift eliminators.
The presenter concluded with the mention of a plant which had to spend $4.5-million to be capable of running during extreme cold weather.
Among the other jewels of knowledge shared at the conference:
- Lessons at the industry level tend to get lost rather than learned. For example, Ercot experienced catastrophic cold-weather events in 1988 and 2011, and then again this past winter.
- Texas has 190 registered “generation owners”; 100 of them are new in the last five years, which means they may not be battle-tested for extreme weather events.
- The 70-member North American Generator Forum (NAGF) focuses on the NERC activity which directly affects the generator segment, and has six working groups, one of which focuses on the emerging cold-weather standard.
- NERC may create a “resilience” standard (in contrast to reliability). NAGF is busy determining the “cost of resilience,” a value to base investment on, since, according to the presenter from the group, organized markets do not support the value of resilience and the costs are born unequally among stakeholders.
