Keeping the fires out and the lights on
Power generation outages caused by fire can be damaging to both fuels and equipment and can take time to resolve, however, these are all too common. When it comes to fire safety and fire protection for power stations, James Mountain, sales and marketing director at Fire Shield Systems Ltd, looks at why the current system needs a rethink.
Our dependence on renewable sources to generate electricity in the UK is growing, and reliability in a constrained power generation landscape is increasingly critical. We need resilience in the diverse system of renewables that are being pressed to meet increasing demands for more climate friendly heat and power.
The National Fire Protection Association’s NFPA 850 recommended practice for electric generating plants and high voltage direct current converter stations has been a central piece of international guidance for fire prevention and protection for power generation for over a decade.
It is a comprehensive handbook that sits amid a complex mix of regulations governing the fire safety of sites where power is generated from combustible feedstocks derived from organic sources, such as wood, agricultural, or refuse-derived sources, such as household waste.
However, chapter nine in the guide devotes just four of its 70 pages to the specific challenges of dealing with alternative fuels, something which is increasingly important for those working within the renewable power generation industry.
Real life experience of consulting on fire safety in sites devoted to the combustion of these alternative fuels reveals a conflicting array of approaches, the majority of which are being dictated by owners who are guided by the insurance industry.
For the insurance industry, the primary concern is to protect the assets, fuels, and equipment, and it tends to rely on traditional protection solutions, such as sprinkler systems, despite these being identified as unsuitable for certain types of feedstocks.
Exploration of alternative systems remains limited. However, different fuels and set ups require different monitoring, detection, and suppression solutions.
Best practice guidance needs to reflect real world scenarios, and the scour incidents that have occurred throughout the past decade, in order to identify lessons learned and better address the evolving risks faced by those within the industry.
What are the risks?
Risks reside in the movement, storage, transportation, and processing of alternative fuels. The complexity comes from understanding the properties of these fuels; how likely these properties are to be consistent; ingress of hazardous materials into these fuels, particularly those derived from refuse, and what happens to the fuels on contact with water and foams.
From carbon monoxide poisoning to explosions, the range of risks is governed by an equally complex array of health and safety legislation. Research into the different aspects of handling the materials and dealing with the associated fire risks are ongoing.
Monitoring and identifying heat and fires within storage can be also complex, as the material is an insulator as well as a fuel, making heat and fire hard to detect until it has taken hold. Some materials also carry the risk of self-combustion.
The potential for the smouldering and slow burn of fires deep within storage has been the subject of a major study from Emerging Risks from Smouldering Fires (EMRIS) between 2015 and 2020.
The need for new best practice guidance
As renewable power generation matures, fire prevention and protection regulations and guidance need to be updated in line with the available technologies and research insight. This is not just a UK-wide challenge, but European and global standards have also been slow to keep pace.
Even factors such as contaminated water runoff from sprinkler or spray systems need to be considered when planning and designing fire prevention, containment and protection systems.
While power generation continues to rely on dated and complex guidance, and faces differing opinions on what constitutes best practice proliferate, the potential for systems to fail and lives to be lost remains.
Ten years on from the introduction of NFPA 850, the time has come to revisit guidance, to ensure a resilient, fire safe future for the UK’s 78 biomass and 48 waste-to-energy power-generating sites.
There needs to be greater clarity around the specific risks that relate to biomass and waste-derived fuels. A comprehensive approach needs to be taken, which looks at all aspects of designing, implementing, and testing systems, that reflects the research and best practice developed over the past decade.
The emerging requirements for on-site battery storage, setting standards for storage of electric and hydrogen-fuelled vehicles, and specific issues related to wind and solar power, should also be given urgent attention.
This robust approach to making fire regulations for renewables fit for purpose should involve multiple stakeholders. The government, regulators, fire safety professionals, academics, and technology partners all have valuable contributions to make.
Their involvement is vital in building long-term confidence in the safety and security of renewables to fuel our homes, transport, and industries in the future.