Learnings

Outcomes

Ensuring the safety of the gas turbine and compressor, especially when operating with hydrogen-enriched gas blends, necessitates a robust fire detection, alarm, and suppression system. Managing the potential risks posed by hydrogen's propensity to escape containment is crucial. If a substantial gas volume were to escape and ignite, the risk of explosion becomes significant, requiring immediate fuel source shutdown as the primary solution in case of a large fire outbreak.

To ensure safety, the plan involves isolating the gas turbine enclosure from the compressor, necessitating separate fire detection and suppression systems for each. Controlling gas concentration levels below the lower explosion limit (LEL) is paramount, and swift detection and suppression of potential fire sources, such as oil mist ignitions, are crucial functions of these systems. Maintaining gas concentration levels even during equipment idle times may require continuous air flow to purge any leaking gas.

Technological advancements in gas leak detection, particularly in acoustic detection of high-pressure gas leaks, show promise. Developments in high-speed digital signal processing and temperature sensing contribute to the creation of sensors tailored for identifying hydrogen leaks, expected to become marketable within three years.

However, challenges persist in detecting hydrogen-fuelled fires using existing flame detection technology, still under development and lacking full substantiation by current testing standards. Manufacturers are beginning to demonstrate operation with hydrogen flames, expecting viable products by 2024/2025.

The use of proven equipment, such as carbon dioxide for localised suppression, is recommended, although challenges exist in interlocks and safety management. Adherence to British standards for fixed equipment carbon dioxide suppression systems (BS5306 part 4, BS EN 12094, BS5839 part 1, EN54, BS7671) guides system operation, defining suitable electrical equipment and interface standards like the 4-20mA current loop.

Compliance with these standards, specifically referred to in National Gas standards, ensures system efficiency and compatibility, vital for this developmental proof-of-concept machine aimed at mitigating risks and equipment damage.

Value tracking  

Data Point                                        Data Point Definition 

Maturity                             TLR2-3                                               Desktop based research project 

Opportunity                       >50% of multiple asset classes         Research project affects our entire compressor cab units 

infrastructure fleet of 24 compressors, could benefit them all 

Deployment costs              -                                                        Deployment cost unknown at this stage of the project 

Innovation cost                  £88,449                                             Cost of innovation project 

Financial Saving                 -                                                        Could contribute to savings by enabling repurposing of existing  

compressor cab infrastructure 

Safety                                 -                                                        Contributes to safe operation of compressor cab when transporting  

Hydrogen 

Environment                        -                                                        Supports transition to net zero through enabling the pivot to hydrogen  

and the associated CO2 abatement. 

Compliance                        Support compliance                         Supports compressor cab safety policies 

Skills & Competencies       Departmental                                   New Hydrogen ready assets to manage 

Future proof                      Supports business strategy              Supports transition to net zero

Lessons Learnt

Initially, the project encountered uncertainties regarding the capabilities of the technology and instruments when handling hydrogen. Specifically, existing standards were tailored for natural gas, lacking specifications for hydrogen usage.

The unique characteristics of hydrogen, such as its density and rapid expansion, rendered conventional measurement techniques ineffective. Detecting hydrogen proved significantly challenging due to its elusive nature, requiring a shift in focus towards suppressing the source as a mandatory measure. Detection strategies predominantly centred on identifying oil fires rather than gas, given the complexities involved.

Moreover, the sheer aggressiveness of hydrogen's explosions rendered previously employed mitigation methods obsolete. Traditional practices like employing blast panels to mitigate explosion expansion proved ineffective in the face of hydrogen's forceful detonations. These revelations highlighted the inadequacy of relying on established methods, prompting the need to reassess and develop new approaches tailored specifically to the distinctive properties and behaviour of hydrogen.

The project's early stages unveiled the inadequacies of standard procedures and the inefficiency of traditional mitigation methods when dealing with hydrogen. Recognising these limitations prompted a reorientation towards novel strategies and technologies essential for handling the unique challenges posed by hydrogen, including its elusive detectability and forceful explosion characteristics.