Measuring Level in a Feedwater Heater

Knowing the level in your heaters is important to ensure you don't allow water into your turbine and to help maximize heat rate. Given that coal plants do more load following than ever, it's important to consider how this affects feedwater heater level. Density changes make it difficult to get an accurate level if you are not compensating for it. Using a guided wave radar device with density compensation can help accomplish this. Last week I saw an Ovation trend screen of a 750MW plant that showed heater level with and without compensation and when load changed, the compensated radar tracked level accurately whereas the non-compensated level did not. The difference was several inches.

With more and more renewables being added to the dispatch stack, fossil plants will have to cycle more. Measurements that didn't matter as much for baseload become more important when your plant cycles.