Accuracy of 'Hydrogen Refueling' Including Nexo to Improve

[Asia Economy Reporter Junho Hwang] Domestic researchers have developed a technology that can quantitatively charge hydrogen. It is expected that the reliability of hydrogen charging transactions, which could not be confirmed whether they were quantitatively charged due to technical limitations, will be significantly improved.

The Korea Research Institute of Standards and Science announced on the 9th that the research team led by Kang Woong at the Thermal Fluid Standards Center developed a hydrogen charging calibration system. This system is a device that verifies hydrogen flow meters to confirm whether quantitative charging has been achieved. It evaluates the accuracy of the flow meter by measuring the mass of hydrogen gas in the system with a precision scale traced back to the national measurement standard.

Quantitative Charging Difficult Due to Different Flow Conditions During Hydrogen Charging

The research team started this study to solve the issue that hydrogen charging at hydrogen charging stations is not quantitatively performed.

Currently, hydrogen charging stations charge fees based on the amount charged. The fee is imposed based on the mass value of hydrogen gas measured by the flow meter inside the charger. In other words, the cost of hydrogen transactions depends on the readings of the hydrogen flow meter. However, since hydrogen is charged under high-pressure and low-temperature conditions, flow measurement is very difficult and the results are uncertain.

In particular, the Coriolis flow meters used at domestic charging stations are calibrated using liquid water at atmospheric pressure and room temperature. This means that calibration for accuracy verification and improvement is conducted under conditions completely different from actual ones.

The research team stated that due to these conditions, it is even difficult to grasp the error range of hydrogen flow meters. The regulations of the International Organization of Legal Metrology (OIML), revised in 2018, set the maximum permissible error for hydrogen flow meters at 1.5% to 2.0%.

Securing Reliability of Hydrogen Charging Transactions

Senior researcher Kang Woong said, "Until now, even if consumers paid a certain amount for hydrogen charging, there was suspicion about whether that amount was truly charged," adding, "The charging amounts calculated from the flow meters of hydrogen chargers and the storage tanks of hydrogen vehicles differ, which could lead to issues with transaction reliability."

He continued, "Once calibration is performed through this system, it is expected that a high level of trust will be established among consumers, hydrogen charging stations, and hydrogen vehicle manufacturers," and said, "If the related legislation currently under review by government departments is amended and the system is applied in the field, it will not only establish order in commercial transactions but also enable the localization of core components for hydrogen charging and measurement."

This technology was developed as part of the institute’s major project, the development of reliability measurement standard technology for hydrogen hybrid stations.

This content was produced with the assistance of AI translation services.