Public Funding for Metrosol Limited

Most industrial processes rely on temperature measurement, which directly influences product quality, energy efficiency, and emissions. All conventional temperature sensors exhibit calibration drift leading to inefficiencies. Poor surface thermometry causes process control problems in advanced manufacturing. Poor gas thermometry causes sub-optimal noxious emissions and reduced efficiency. This project will overcome specific process control challenges by implementing embedded traceable thermometry in-situ through driftless practical primary thermometry and self-validation, gas/combustion thermometry, and new traceable surface temperature measurement methods. Traceability will be either directly to the redefined SI kelvin, or indirectly via the International Temperature Scale of 1990 (ITS-90).

This project aims to develop a fundamentally different type of thermometer (based on the measurement of Johnson noise) that will not drift. Conventional thermometers are "secondary thermometers" in which a property is measured that is affected by temperature, for example most digital thermometers measure either the resistance of or the voltage produced by the sensor. However, the property measured can be affected by other things so these thermometers drift as they age. This new thermometer is a "primary thermometer" in which the parameters measured are linked directly to temperature by a fundamental physical law, which does not change with time. The phenomenon has been known for a long time, but the signals involved are so small that it has not, so far, been possible to make these measurements reliably in a typical industrial environment. A new approach to measuring Johnson noise will be employed that overcomes the problems that have so far prevented this technique from being used to measure temperature in industrial applications. A successful, commercial Johnson noise thermometer is expected to capture a significant share of the high-performance segment of the industrial temperature measurement market.

Metrosol Limited, an established manufacturer of high precision temperature metrology products, will collaborate with NPL (the National Physical Laboratory) in the development of a novel type of thermometer based on Johnson Noise. This thermometer will be driftless and as such will improve the measurement of temperature in nuclear power plants. The measurement of temperature is crucial to the safe operation of these plants so this technology will assist in continuing to provide safe nuclear power in the future. It will also enable nuclear power plants to operate safely at higher temperatures, which will improve efficiency. An initial target is to improve efficiency by 3.3% , which would reduce the cost of electricity generated by nuclear by the corresponding amount and also displace higher carbon sources. With the current generating mix planned by the UK government, the efficiency improvement would reduce carbon emissions by 4,100t (metric tonnes) per day or 60 million tonnes over the life of the reactors.