I highly recommend reading this month’s Power Magazine – especially the article starting on page 66; Entergy’s ‘big catch”. It’s a great example of how performance monitoring – with all the best tools and personnel – can make a huge impact on a plant’s performance and, more importantly for many, it’s reliability.
Most notably, the company in the article (Entergy) had setup a central performance monitoring and diagnostic center, where they had 24×7 support for equipment monitoring. The central staff was looking for performance losses, but also at reliability issues, such as increases in vibrations, temperatures, and other parameters which might indicate an imminent failure. The plant staff soon learned that this central group of professionals was there “not looking over their shoulder, but rater, watching their back.”
For a lot of plants, a central diagnostic center may be financially out of reach – although, when you consider the potential savings in forced outages and maintenance costs, it’s harder to make that argument. But, any additional observations you can make will support increased intelligence of plant operation which can lead to finding that abnormal condition before a catastrophic event occurs.
Just constantly trending your overall net heat rate in real time, where the control room operator can view it as time allows, will start the ball rolling. It’s not much – but it’s something. Small Steps. Kaizen. Once real time heat rate is being consistently monitored, you’ll start to see why a corrected heat rate can be helpful – changes in heat rate at full load become more apparent when corrected to a common baseline conditions.
Setting up a corrected heat rate trend does not need to be a large undertaking. Some information from the OEMs may be necessary, but again, taken in small steps, it can be fit into nearly any operating budget – and the time to payback is often very short. Errors in fuel metering are commonly found once heat rate is scrutinized relative to a set of reference conditions. Bad heat rate assumptions can lead to poor dispatch assumptions – which lead to operating in poor markets, or not operating in profitable ones.