Pre-drying of lignite before feeding to the boiler is a potential way to increase the net efficiency of lignite-fired power plants. Lignite pre-drying is, however, a high energy consumption process with a high risk of spontaneous ignition. If the lignite is dried at low temperature, the...

Performance criteria, such as efficiencies and coefficients of performance, for energy systems, are commonly used but often without sufficient understanding and consistence. The situation becomes particularly incoherent when simultaneous energy interactions of different types, such as work,...