This paper presents methodologies and equipment for SI-traceable inline measurements of water content (a critical quality parameter) in solid biofuels. Inline measurement systems for water content are commonly used at CHP plants, providing continuous real-time data. However, the accuracy of these systems is in most cases unsatisfactory, mainly because the systems are not calibrated representatively for the relevant material, and until now, calibrations traceable to the SI system have not been available. To provide reliable and accurate inline water content data, new procedures and equipment for calibrating measurement systems were developed. Two reference methods for the determination of water content were developed; one measures the airflow and dewpoint of desorbed water in the air passing a test sample, while the other uses a P₂O₅-sensor. Additionally, a transfer standard based on a cavity resonance sensor was developed for fast onsite calibration of the inline sensor at the power plant. This new instrument allows for quick and accurate measurements. The transfer standard is made metrologically traceable to the primary measurement standards. The entire system was demonstrated by calibrating an inline microwave-based (MW) sensor at the CHP plant of VERDO in Randers, Denmark. Thus, a complete metrological traceability chain was established from an industrial to a primary standard.

Dynamic measurements, particularly in thermometry, are crucial for capturing rapid variations in physical systems. However, such measurements face challenges due to noise, system distortions, and the inherent uncertainty of capturing time-dependent phenomena. This study presents a methodological approach to improve dynamic measurements through advanced signal processing and calibration model enhancement. By integrating Fourier transforms, dynamic Kalman filtering, and temperature correction models, the research aims to enhance precision while ensuring traceability. The results demonstrate the effectiveness of these approaches in providing reliable, accurate, and standardized measurements for industrial and scientific applications.