Friday 26 December 2014

Peat fires and carbon loss

Together with co-authors in Canada, US, UK and Netherlands, we have just published a progress article in Nature Geoscience  (vol 8, 2014) on the carbon losses from peat fires: Global vulnerability of peatlands to fire and carbon loss.

Ssmouldering combustion of dry peat.Available at Imaggeo.
In the paper we review how fire is a threat to the naturally stored carbon in peatlands and has the potential to drastically disturb the carbon stocks. While dry peat is a very flammable substance because it is a porous and carbon-rich, the amount of carbon stored in peatlands exceeds that stored in vegetation globally. Peat fires are dominated by smouldering combustion, which is ignited more readily than flaming combustion but is more difficult to suppress. In fact smouldering fires can persist deeper and in much wetter conditions than flaming fires. In very wet or flooded peatlands, most of the carbon stock typically is protected from smouldering, and resistance to fire has led to a build-up of peat carbon storage in boreal and tropical regions over long timescales. But drying as a result of climate and human activity (eg, drainage) lowers the water table and increases the frequency, depth and extent of peat fires. The combustion of deep peat affects older soil carbon that has not been part of the carbon cycle for centuries to millennia, and thus dictates how fire emissions affect the carbon cycle and feedbacks to the climate.

Monday 22 December 2014

Fin's and Candle's Creative Contests

Engineering can be the most creative profession, but we engineers are in general not the best communicators nor the best at appreciating arts. These are not really topics of interest in Engineering Schools around the world.
Sir John O'Reilly said it better during the 2014 Mountbatten Lecture at the Royal Institution, "Engineers should embrace the arts as being key to creativity and an important component of innovation, crucial to creating new products and boosting future competitiveness". Sir John is also proposing to change STEM to STEAM (science, technology, engineering, arts and maths) and he has my support.

I always want to build on this and encourage somehow my students' motivation on communications and the arts. So this year, again, I started the academic year with Creative Contests for each my courses at Imperial College: ME2 Heat Transfer and ME4 Combustion. The instructions to participate were the following: "I have three extra copies of the textbook to give away. If interested, send me a poem, comic, drawing, painting, song, video, or anything creative that explains why you are taking this course. Art, wit and humour are allowed, even encouraged". I show below the submissions; congratulations to the winners (I wish an extensive use your new awarded textbooks).

2014 Fin's Creative Contest in ME2 Heat Transfer: 

I was the sole jury and found three winners (the first three shown here), each received a hard copy of Incropera's Foundations of Heat Transfer. These are the submissions:



  • Instrumental composition written and played by Daniel (note: the piano stands for convection in water, the mandolin for an insulator and the djembe for conductive material)



  • The Infamous Microwave problem drawn by Riyadh
     


  •  Roses are red written by Daniel


  • Heat Transfer poem written by Sofie



  • The Phoenix painted by Johan
     



  • Cold hands and feet written by Rob
     

  • There was once a man called Guillermo written by Thomas

  • Who needs to learn Heat Transfer? drawn by Adrian




  • Heat Transfer Hits Volume 1 collected by Hisham

  • Letter to Incropera written by Anni



  • 2014 Candle's Creative Contest in ME4 Combustion 

    I asked the class to be the jury via a Memtimeter survey and they found three winners (the first three shown here), who got a hardcopy of McAllister's Fundamentals of Combustion Processes. The three runners up (following three submission) got a copy of Faraday's Chemical History of a Candle. These are the submissions:



  • Tournament website created by Sven


  • The Burning Crusade drawn by Qunli


  • How many combustion phenomena can you find? drawn by Haoxiang

  • Life of a candle composed by Wei




  • Flames painted by Franz
     




  • Our modern life composed by Siying

  • Shock diamond selected by Francis  (credit: Swiss Propulsion Laboratory

    Note: see here for the 2013 Contests I organized last year

  • Saturday 27 September 2014

    Forecasting the movement of a wildfire

    I have a dream too. That one day we could predict the movement of a fire and be able to inform the Fire Service ahead of time by using just an iphone.

    Hopefully our recent paper (published in open access) in Natural Hazards and Earth System Sciences moves us closer to that end, as it reports an algorithm that can forecast the movement of a wildfire when observations of the locations of the flames are available.


    Five assimilated fire fronts with 1 min intervals (black solid lines). The first guess (red dashed line) is taken to be far from the true invariants vector to check the algorithm capability to converge. A 10 min forecast (blue solid lines) is also calculated using fuel depth as sensor data.
    The title of the paper is "Forecasting Wind-Driven Wildfires Using An Inverse Modelling Approach". The fire model at the core of the forecast algorithm combines the classical theory of Rothermel's rate of spread with a perimeter expansion model (based on Huygens principle for the propagation of waves). We then pose the  problem as an optimisation and force our fire model to predict well any past observations of the real fire that might be avaible at that moment. Observations of the location of the fire can be produced from any system like from personnel in the field (deployed fire fighters), drones, airplanes or satellites. Once all the past observations are predicted, we consider that we have found the true characteristics of this particular fire and launch forecasts into the future. Where would be this fire be in 10 min or 1 h?

    We have investigated the skills of the algorithm using synthetic data (not real fire data) and the results show it is very quick and decently accurate, and predicts the location of the front ahead of time. It needs further work to increase its accuracy, of course, but we already see the greatest strengths of our method are lightness, speed and flexibility. We specifically tailor the forecast to be efficient and computationally cheap so it can be used in mobile systems for deployment by the Fire Service. For example, in an iphone.

    Hope Apple knock on our door one day.

    Sunday 3 August 2014

    Welcome Nils to Imperial Haze Lab


    July was the first month of Nils Roenner at Imperial College London as a new PhD student in m group. He joins the Imperial Haze Lab in the Department of Mechanical Engineering.

    Nils is from Germany. He has just graduated with an MEng degree in Mechanical Engineering from Imperial College. In his final year project, he studied numerically the pyrolysis and ignition of polymers subjected to transient irradiation. During his degree, he has also work on a novel device for energy recovery from wood burning stoves. During the summers, he hold internships in several companies, spanning the foundry, mechatronics and electronics sectors.

    The preliminary title of his thesis is "Experimental Investigation on the Boosting of Flame Retardancy in Thermoplastics" and is funded by BASF, Germany. The aim of the thesis is to provide a better understanding of the fundamental chemical and heat transfer processes involved in the ignition of thermopastics. In this work, Nils aims at improving the prevention of residential and industrial fires.

    Monday 16 June 2014

    Nature’s sport and the Burning Mountain

    Figure 1. Newspaper excerpt from 1828 announcing an active volcano in Australia.
    Thanks to his knowledge in geology and an investigation of the site, Reverend Charles Wilton ended the rumors of an active volcano in Australia (Fig. 1). In 1829, Rev. Wilton visited Mount Wingen in New South Wales, Australia, and pronounced the phenomenon to be unique, "one other example of nature’s sports", a fire that had been burning for a very long time, "far preceding the memory of man". Indeed, wingen is the word for fire in the aboriginal language of the local Wonaruah tribe.


    Mount Wingen, 530 m above sea level, is the highest of two contiguous hills in the Upper Hunter Valley. It is located 25 km North of Scone via the New England Highway and approximately 4 hr drive from Sydney. Its official name is the Burning Mountain Nature Reserve, and I had the pleasure of visiting it in early February 2014 (Fig. 2). The visit fulfilled one of my most desired field trips. I was attending the 11th International Symposium on Fire Safety Science in New Zealand, and I could not forgive myself from a quick stop over to see the Burning Mountain.



    Figure 2. Entry to the Nature Reserve of The Burning Mountain, including my symposium bag.

    The nature's sport that Rev. Wilton was referring to is the smouldering combustion of a coal seam. The Burning Mountain is the best example of this natural phenomenon that slowly burns the underground coal when it becomes exposed to atmospheric air.  Smouldering is the slow, low-temperature, flameless burning that represents the most persistent type of combustion phenomena and leads to the largest and longest burning fires on Earth. This Australian coal seam started to burn more than 6,000 years ago, some scientists think more than 500,000 years ago. At least the British cannot be blame for it.

    The fire is burning now about 30 m below ground. At a rate of 1 m per year, the fire has reached the top of the hill (shown in Figure 3). Because of the creeping spread rate, the slow and intense heat has created a landscape clear of any vegetation in an area 50 m around the hill top. The soil shows a beautiful colour palette of white sinter, yellow sulphate, black char and red iron oxide. Where the fire and heat has not reached yet, a healthy green forest of mature and tall trees can be seen on brown soil. Along the former trail of the fire path, the forest grows back slowly, and young and smaller trees can be seen on red soil. Once at the hilltop, it is easy to feel the hot combustion gases and the smell of sulfur released from multiple deep cracks. The site is surrounded by cracks, some are up to 0.5 m wide, which are more visible ahead of the fire than behind it. Further from the active site by about 20 m, the cracks do not emit gases which to me indicates that the airflow direction is into the seam, feeding the fire with vital oxygen.

    Figure 3. The fire has now reached the top of the second hill, where the soil is also a multicolor palette of white sinter, yellow sulphate, black char and red iron oxide.
    Some of the most interesting observations that the visitor can do are visually inspections of the trail the fire has left in the area as it has spread for centuries. The entry to the walking track is from the New England Highway, about 1km North of the current fire location (Fig 4). As the visitor walks in from the parking lot, the track goes up to the tallest of the two contiguous hills. Near the hill top, the visitor meets the first clear signs of the fire trail, and then the track follows it chronologically. The fire was burning below the hill top circa 1500s (my estimate). One can see a clear change to less dense vegetation, soil of a strong red colour and more large rocks on the ground. Then, the track goes down a few dozen meters to the saddle point between the two hills and then up to the current fire site. This saddle point is close to where the fire was when it was reported first and confused for a volcano in 1828. I think that the lower ground elevation at the saddle point means the distance between the free surface and the burning seam was at a minimum. Hence, I infer than the much increased air supply contributed to the ferocity of the burning and the plume of smoke ought to have been majestic. The depth to the seam might have been short enough that the coal walls could be seen glowing red. Lava they thought?. This would be nothing compared to the faint hot gases released now that the fire is again at a hill top and more than 30 m deep.


    Fig 4. Google maps of the reserve showing the approximate track and the current location of the fire at the top of the second hill.

     An interesting observation that I could make during my visit is that after the hilltop, the forward path of the fire, just 20 m away, is on a very steep fall of 100 m down to the bed of a small river. If the coal seam is running just under the river, the fire could reach again massive proportions as in 1828. Or it could be that the coal seam does not continue after the hill top, and that the fire will naturally extinguish itself within my lifetime after more than 6,000 years burning. Either way, what a lucky historical coincidence for me to witness it happening. I will not miss another visit in the next decade.

    The Burning Mountain is just one example. Thousands of underground coalmine fires have been identified around the world, especially in China, India and USA. Elusive, unpredictable and costly, coal fires burn indefinitely while there is fuel, choking the life out of a community and the environment while consuming a valuable energy resource. The associated financial costs run into millions of dollars including the loss of coal, closure of coal mines, damage to the environment and fire-fighting efforts. There are other well-documented cases like when in 1962 an abandoned mine pit in Centralia, Pennsylvania, USA was accidentally lit. Many unsuccessful attempts were made to extinguish it, letting the fire continue to burn until today after more than forty years. Geologist estimate that there is fuel for 250 years more of fire.


    Recommended reading (and viewing) on smoldering fires:
    • Abbott, W.E., 1918. Mt. Wingen and the Wingen Coal Measures. Angus & Robertson, Sydney. http://trove.nla.gov.au/work/21299713
    • Mayer, W. , 2009, Geological observations by the Reverend Charles P. N. Wilton (1795 -1859) in New South Wales and his views on the relationship between religion and science, Geological Society, London, Special Publications 310, p197-209. http://dx.doi.og/10.1144/SP310.20
    • Smouldering, Wikipedia, http://en.wikipedia.org/wiki/Smouldering
    • Smouldering Fires and Natural Fuels, by Guillermo Rein, Chapter 2 in:
      Fire Phenomena in the Earth System – An Interdisciplinary Approach to Fire Science, pp. 15–34, Wiley and Sons, 2013. http://dx.doi.org/10.1002/9781118529539.ch2
    • Stracher, G.B., Prakash, A. & Sokol, E.V. (eds) (2010) Coal and Peat Fires: A Global Perspective, 1st edn; vol. 1: Coal – Geology and Combustion. Elsevier Science
    • Pennsylvania's 50-Year-Old Coal Fire by SciShow. www.youtube.com

    Friday 13 June 2014

    Forecasting Wildfires and Natural Hazards

    A technology able to rapidly forecast wildfire dynamics would lead to a paradigm shift in the response to emergencies, providing the Fire Service with essential information about the ongoing fire. In this recent paper that we have published [*] in the journal Natural Hazards and Earth System Sciences, we present and explore a novel methodology to forecast wildfire dynamics in wind-driven conditions, using real-time data assimilation and inverse modelling.

    The forecasting algorithm combines Rothermel's rate of spread theory with a perimeter expansion model based on Huygens principle and solves the optimization problem with a tangent linear approach and forward automatic differentiation.


    Its potential is investigated using synthetic data and evaluated in different wildfire scenarios. The results show the capacity of the method to quickly predict the location of the fire front with a positive lead time (ahead of the event) in the order of 10 min for a spatial scale of 100 m.

    The greatest strengths of our method are lightness, speed and flexibility. We specifically tailor the forecast to be efficient and computationally cheap so it can be used in mobile systems for field deployment and operativeness. Thus, we put emphasis on producing a positive lead time and the means to maximise it.

    [*] O.Rios, W. Jahn, G. Rein, Forecasting wind-driven wildfires using an inverse modelling approach, Natural Hazards and Earth System Sciences 14, pp. 1491-1503, 2014. http://dx.doi.org/10.5194/nhess-14-1491-2014 (open access) 

    Tuesday 8 April 2014

    G3E4O Geoengineering and the Engineers of Gaia

    Earthrise seen by the Apollo 8 crew, 1968. Credit: NASA
    Blog by Nils Roenner and Guillermo Rein, Department of Mechanical Engineering at Imperial College London.


    Because of global concerns on climate change, engineers are called to have a leading role in tackling the problem, and a new discipline is being proposed: Geoengineering (G3E4O(IN)2R).
    The realisation that man has an impact on Earth has led to the idea of the Anthropocene which signifies the current geological epoch, ‘the recent age of man’. Humans are being viewed as a factor and intricate part of nature. This is in agreement with Dr Lovelock’s Gaia hypothesis, introduced in 1979, a revolutionary view of the Earth not as a simple accumulation of systems but as one self-regulating system encompassing everything, including life.
    Sketch of the Earth as system of systems with interdependencies and feedback lines outlined. Adopted from Rial et al. 2004 (10.1023/B:CLIM.0000037493.89489.3f).
    In an article we wrote in 2013, The Engineers of Gaia, by using the concept of Gaia and the Anthropocene as starting points, we argue that the control system view of Earth is a vital part of geoengineering. It is not about one mechanism, it is about the self-regulating system as a whole. But if geoengineering was to apply a forcing too large or at the wrong place, such that positive feedback loops overtake, the results could be drastic and unpredictable. Careful and robust control is required when engineering something as vital as the system Earth, and this argument is often invoked to stop geoengineering proposals. Paraphrasing Prof Henry Petroski, for us, the premise would be that geoengineers welcome all the relevant science they can muster, but cannot wait for complete scientific understanding before acting to save life or create a new planet-saving technology. We also maintain that up until the moment when adequate understanding and models of the system are found only reversible and well controlled geoengineering interventions should be applied on a large scale, in order to prevent uncontrollable feedback being set off or reaching tipping points by accident.

    The term geoeneering has only recently gained traction in the public debate, and its definition still varies according to the source. We think this can be defined as the large-scale anthropogenic intervention into the system Earth in order to adjust planetary mass and heat transfer processes, such that global catastrophes can be mitigated. Geoengineering opens up a broad range of measures with which global climate change can be tackled. No geoengineering approach should be viewed as a single solution to all of the problems associated with climate change. Most likely a combination of approaches will yield long term success. 

    Our article briefly evaluates four promising applications of geoengineering using a set of criteria by which geoengineering proposals can be evaluated in term of feasibility, effectiveness, safety, geointervention, and costs.  These are summarized here:

    Carbon Capture and Storage is a good option for rich countries aiming at reducing its CO2 emissions from power plants. Apart from its high cost, this method is very feasible and effective with low levels of geointervention and risks.

    Biomass Burial is a good option for countries that have suitable and extended land. It is a lower cost approach and can be scaled up to have a larger impact. Low cost, feasibility, effectiveness and low levels of geointervention speak in favour despite some risks, like fire, which need to be managed.

    Iron Fertilisation of oceans is an option for countries with coastal access. The low cost involved and the proven feasibility make this method appealing. But concerns about low effectiveness, high level of geointervention and high risks question the validity of the approach.

    Cool Roofing of Building is a good approach for densely populated areas or countries with high annual level of sunshine. The low cost, risks and level of geointervention of this feasible option are attractive but on the other hand, it has a weak effectiveness and cannot control secondary effects.

    Illustration of the strengths and weaknesses of the proposals under study.
    It can be said for all geoengineering proposals, that due to our incomplete understanding of all feedback and threshold points in the global system of the Earth, the topic has to be approached with great caution. But its potential in helping to solve the great problem of climate change, make the efforts put into research and experiments worthwhile.


    Tuesday 1 April 2014

    Welcome Francesco to Imperial Haze Lab

    Today was the first day of Francesco Restuccia at Imperial College London as new PhD student in m group. He joins the Imperial Haze Lab in the Department of Mechanical Engineering.

    Francesco is from Italy. He became  a Mechanical Engineer from the University of Edinburgh in 2012, and then obtained an MSc degree from California Institute of Technology in 2014. At Caltech, Francesco studied numerically the problem of accidental ignition of liquid fuel tanks. At Edinburgh, he worked on smart distribution networks and renewable energies. He also spend time conducting experiments at CERN Cryogenics.

    The preliminary title of his thesis is "Computational Study of Porous Reactive Media" and is funded by EPSRC. The aim of the thesis is to provide a better understanding of fundamental smouldering phenomena to aid in the mitigation and prevention of peat and coal fires. This is frontier research at the interface between combustion science and Earth sciences.

    Friday 7 March 2014

    Welcome Izabella to Imperial Haze Lab

    Izabella, new PhD student
    Last week was the first day of Izabella Vermesi at Imperial College London as my new PhD student. She joins the Imperial Haze Lab in the Department of Mechanical Engineering.

    Izabella is a Civil Engineer from the Technical University of Cluj-Napoca, Rumania, since 2011. She then obtained an MSc degree from the Technical University of Denmark (DTU) in 2013. At DTU, Izabella worked on multiscale modeling of tunnel fires and assisted in the teaching of Building Fire Safety course.

    Note: Izabella has her own blog now, visit http://izabellavermesi.blogspot.co.uk

    The preliminary title of her thesis is "Computational Pyrolysis and Ignition under Transient Radiation", and is funded by FM Global USA.


    She is to conduct a computational study of pyrolysis on a range of solid fuels when subjected to a radiant source whose power is transient, a long pulse, as opposed to the constant power typical assumed in ignition theory. This scenario, rarely studied in fire science, is related to flame spread, secondary ignition, travelling fires in compartments, and wildfires. The framework of study will be such that work goes from simple to more complex models and fuels and that the computational complexity is added only when actual results justify it.

    Monday 24 February 2014

    The pyrolysis history of Perspex

    We sent the image below, The pyrolysis history of Perspex, to the Fire Science Image competition at the 11th International Symposium on Fire Safety Science.


    Photo by N. Roenner and G. Rein (Imperial College London) and R. Hadden (University of Edinburgh)
    This composite shows the pyrolysis and burning of a sample (10 cm x 10 cm x 1.5 cm) of transparent Poly-methyl methacrylate (PMMA, Perspex) inside a Fire Propagation Apparatus (FPA).
    The central image shows the diffusion flame established on top of the sample which is surrounded by the infrared lamps emitting a transient heat flux peaking at 30 kW after 300 s. The series to the right show the evolution of the PMMA sample during the fire. This was created by extracting samples at different times from identical experimental repeats.
    PMMA is typically chosen for fire experiments because it is the polymer for which the flammability behaviour is best known. Despite this, the intricacy involved is patent. The melting, bubbling and pyrolysis mechanisms all contribute to create a dynamic image of the sample's history which illustrate the high complexity and beauty of fire phenomena. 
    Licensed under a Creative Commons CC BY-NC-ND 3.0.

    Computational Smouldering Combustion

    I am delighted to announce that our work won the award for the Best Student Poster at the 11th International Symposium on Fire Safety Science, with the research on peat fires led by my PhD student X. Huang.

    Fire Watch Constellation

    I am delighted to announce that we won the award for the Best Fire Science Image at the 11th International Symposium on Fire Safety Science, with our entry titled Fire Watch Constellation (reproduced below).
    Note: We have posted the image on the image repository of the European Geosciences Union
    http://imaggeo.egu.eu/view/2446.


     Photo by E. Rackauskaite, X. Huang and G. Rein, Imperial College London. 
    This composite shows a constellation of combined visual and infrared imaging of a smouldering combustion front spreading radially over a thin sample of dry peat. The central watch is created by a series of twelve wedges. Each edge is extracted from a photo taken every 5 min from an elevated view looking down into the sample during the one-hour lab experiment. The circular peat sample (D=22 cm) was ignited on the centre by an electrical heater. The average radial spread rate was 10 cm/h and the peak temperature 600˚C. The top figures show the virgin peat (left) and the final residue (right). The bottom figures show the wedges in visual (left) and infrared (right) imaging. Smouldering combustion is the driving phenomenon of wildfires in peatlands, like those causing haze episodes in Southeast Asia and Northeast Europe. These are the largest fires on Earth and an extensive source of greenhouse gases, but poorly studied. Our experiments help to understand this emerging research topic in climate-change mitigation by characterizing the dynamics of ignition, spread and extinction, and also measure the yield of carbon emissions. 

    Licensed under a Creative Commons CC BY-NC-ND 3.0.

    Friday 31 January 2014

    Wind Turbines on Fire

    In a few weeks, we are presenting in Christchurch, New Zealand, a brief paper [1] on the impact of fire in wind turbines.


    The wind energy is one of today’s leading industries in the renewable energy sector, providing an affordable and sustainable energy solution. However, the wind industry faces a number of challenges, one of which is fire and that can cast a shadow on its green credentials.


    We have found that fire is the second leading cause of catastrophic accidents in wind turbines (after blade failure) and accounts for 10 to 30% of the reported turbine accidents of any year since 1980’s (18/7/2014 Update: "since 1990's"). 

    [March 2014 Update: The video of the talk, presented by co-authored Dr Carvel, can be watched here:]

      
    The total number of turbine accidents recorded in the period 1995-2012 was 1328. The most common cause of accidents in wind turbines is blade failure with 251 registered instances (19%). It is closely followed by fire with a total of 200 incidents recorded, which is 15% of all the reported accidents. This represents on average 11.7 fires per year (~one fire accident per month). This figure of turbine fires per year may not seem a great number compared to the fact that there were ~200,000 wind turbines worldwide in 2011. However, due to the excessive financial loss that a fire can cause, especially in a small wind farm, it is an issue that owners and insurers are keen to address. But we argue that this is only the publicly available tip of the iceberg representing about 10% of the total number of fires. A rough average estimate of the real figure is 117 fire accidents per year (ten times the figures reported publicly).

    [18/7/2014 Update: Our 10-times extrapolation that we apply in the paper is based on the assumption of uniform failure rates for all failure types (blades, fire, structure, etc). This assumption is not a strong one and would need to be double check with higher quality data. Among all the conclusions of our paper, I feel that the 10-times higher number of fire accidents is not the most important or stronger one. We could have emphasized this weakness.
     Once more, I would like to defend the robust fire safety record of the wind industry worldwide, because a frequency of 1 fire per 10,000 turbines that our paper reports makes wind one of the safest energy source].


    Instances of reports about fires in wind farms are increasing, yet the true extent of the impact of fires on the energy industry on a global scale is impossible to assess at the moment. Sources of information are incomplete, biased, or contain non-publically available data. The poor statistical records of wind turbine fires are a main cause of concern and hinder any research effort in this field. This paper aims to summarise the current state of knowledge in this area by presenting a review of the few sources which are available, in order to quantify and understand the fire problem in wind energy.


     

    The three elements of the fire triangle, fuel (oil and polymers), oxygen (wind) and ignition (electric, mechanical and lighting) are represent and confined to the small and closed compartment of the turbine nacelle. Moreover, once ignition occurs in a turbine, the chances of externally fighting the fire are very slim due to the height of the nacelle and the often remote location of the wind farm.

    The main causes of fire ignition in wind turbines are (in decreasing order of importance): lighting strike, electrical malfunction, mechanical malfunction, and maintenance. Due to the many flammable materials used in a wind turbine (eg. fiberglass reinforced polymers, foam insulation, cables) and the large oil storage used for lubrication of mechanical components, the fuel load in a turbine nacelle is commonly very large. Our paper [1] finishes with an overview of the passive and active protection options and the economics (costs, revenue and insurance) of wind turbines to put in context the value of a loss turbine compared to the cost and options of fire protection.

    We hope that this paper will encourage the scientific community to pursue a proper understanding of the problem and its scale, allowing the development of the most appropriate fire protection engineering solutions.

    [1] Overview of problems and solutions in fire protection engineering of wind turbines, by S Uadiale, E Urban, R Carvel, D Lange and G Rein, 11th Symposium of the International Association for Fire Safety Science, New Zealand, Feb 2014.