Photovoltaics and fire

PUBLISHED
14 June 2023

AUTHOR
Jim Foran

SHARE
 

Photovoltaics and fire

As the movement towards renewable energy gains momentum, Jim Foran looks at the potential serious and unmitigated electrical safety risk posed by solar panel fires.

Photovoltaic (PV) systems, commonly known as solar panel systems, are a growing challenge for first responders, including fire and emergency services personnel as well as electrical contractors. Whether responding to a solar panel fire, a fire at a structure featuring solar panels, attending to storm damage, or encountering a property that has a faulty or substandard solar system installed, solar panels pose a serious risk to safety due to their capacity to produce potentially lethal amounts of DC electricity as long as the solar PV system is exposed to light.

Solar panel systems are emerging as a new and growing incident category, yet current standard operating procedures (SOPs) still do not adequately address the increasingly obvious safety gaps. Fire and emergency service crews are likely to face solar panel incidents on a daily basis in the near future, but without adequate tools, procedures, or training, dangerous scenarios may become more common and increasingly put lives at risk.

Government figures confirm that the use of solar PV to generate electricity in the UK has grown rapidly since 2010, increasing capacity from 95 MW to 14,900 MW (14.9GW) at the end of March 2023. There are now over 1.2 million solar PV installations in the UK which accounts for approximately 5% of total electricity generation in the UK.

With rising energy prices, interest in solar PV installations is growing exponentially, especially as householders emerge from fixed-rate energy deals to the shock of record-breaking energy price increases.

The rules governing solar PV safety

As detailed by the National Building Specification (NBS), the current safety requirements include several standards that PV products should comply with (BS EN 61730-1, BS EN 61215, BS EN 61646, MCS 0065), and include – amongst other factors – requirements that address fire hazards. The Microgeneration Certification Scheme (MCS) provides building owners with a measure of confidence in the installers and products used.
Furthermore, PV systems that form part of the roof structure should satisfy a fire exposure test, e.g., DD CEN/TS 1187 test 4 or BS 476-3. This test seeks to ensure that fire will not spread between buildings via the roofs.

Alongside the above standards, the FPA has recently published RC62 Recommendations for fire safety with PV panel installations. Developed as a Joint Code of Practice by RISCAuthority and the MCS, with the support of Solar Energy UK, the primary focus of this document is the prevention and mitigation of fires involving PV systems. The Code applies to all stages of a project: planning, procurement, design, installation, operation, and maintenance. With the exception of some niche applications, the scope relates to roof-top installations on commercial and multi-residential buildings up to and including larger utility-scale projects. While commercial
ground-mounted PV systems are not covered in detail in the guide, the risk control principles discussed are similar.

The risks related to solar panels

Notwithstanding these regimes for installers and products, there is currently no national UK guidance specific to fighting fires involving PV systems, despite PV systems presenting new risks to firefighters, especially from the risk of electric shock and electrocution. However, the BRE National Solar Centre has carried out some in-depth analysis of the causes and challenges of solar PV fires as uncovered by previous incidents in the UK.

As outlined in the BRE Report, Fire and Solar PV Systems, it is difficult to locate accurate data and statistics relating to solar panel fire incidents in the UK, with the same true for most countries around the world. 
Currently, there is no reporting field for solar panels in the UK national incident reporting system, which makes it impossible to measure the true impact that solar panels have upon national fire incident data or firefighter safety. If it cannot be measured, it cannot be managed, and for this reason it is critical that this data gap is recognised and addressed without delay, and that a reporting field for solar PV systems be added to the national incident reporting system so that stakeholders have the right information to make evidence-based decisions rather than opinion-based decisions which are the status quo of today. There is no doubt that the true statistics on incidents involving solar panels are significantly under-reported and the true costs in terms of property damage, revenue loss, and work health and safety liabilities are yet to be determined and accurately measured.

The DC Danger Zone

The primary risks associated with solar panels are electric shock and electrocution. As long as solar panels are exposed to light, they will continue to produce potentially lethal amounts of direct current (DC) electricity, known within the industry as the ‘DC Danger Zone’. This means anyone operating near a solar panel system during daylight hours is always engaging with live electrical equipment.

To put the risk of solar panels into perspective, a domestic 230-volt AC power outlet is usually rated at 10 amps and provides 2,300 watts of power. The average size of a residential solar PV installation in the UK is 4 kilowatts, usually configured in multiple strings of up to 600 volts per string. With up to 10 amps available, the average residential solar PV array can produce up to 4,000 watts of power. Residential installations of up to 10 kilowatts are now common, while commercial installations can be upward of several hundred kilowatts, and generation plants can exceed 100 megawatts or more. Even small domestic systems have the capacity to injure via electric shock and kill by electrocution. The physiological impacts from 600V DC current exposure can be represented as follows:

Physiological effectDC threshold limit for adult (milliamps)
Mild shock reaction2 mA
Lock on40 mA
Electrical burns70 mA
Ventricular fibrillation240 mA

Better training and equipment needed

One of the challenges surrounding solar panel safety is the simple fact that the technology is relatively new and has grown so quickly. There are very few true experts in the field of solar safety and authorities are only just starting to recognise the education and safety gaps. Because of this, emergency service personnel are at risk of making fatal errors on the job.

For example, the practice of tarping damaged solar panels is extremely dangerous and operates in clear breach of standard operating procedures (SOPs), which state that crews should assume the solar power system and surrounding area is live. SOPs mandate an exclusion zone of at least three metres be established around any damaged solar panel components, and the exclusion zone be increased to eight metres if the components are in contact with conductive materials. Tarping solar panels is an outdated but persistent practice that is done with good intentions, but is ultimately a dangerous solution.

The full scope of solar panel risk

Sandwiched between the protective glass, frame, and back-sheet of the solar panel, solar cells present no risk to health, but once a panel burns and the solar cells are exposed, the burning panels can be highly toxic and dangerous to humans and the environment. Solar cells contain carcinogens, cadmium telluride and gallium arsenide, as well as potentially lethal phosphorous. Inhalation of these toxic nano-particles cause silicosis of the lungs and should be treated with the same precautions as asbestos. Self-contained breathing apparatus (SCBA) should always be utilised in incidents involving burning solar panels.

With solar panels now being installed on an ever-growing number of homes and businesses across the UK, it is important to consider the broader range of incidents involving structures and fire. For every incident initiating from a fault in the solar panel system, there are many more where the ignition point is totally unrelated, but where the fire may encroach upon the solar panel system and compromise safety. In these scenarios, it is just as important to isolate the power from the solar panel system as it is to isolate mains power from the grid. Up until now this has proven problematic for firefighters and in many cases defensive tactics have been employed because solar panel systems could not be easily or reliably isolated, increasing property damage and insurance claim costs at properties featuring solar panel systems.

Solar safety technologies

There are a range of electro-mechanical solutions available on the market including isolation switches, micro-inverter systems, and DC optimizing equipment (broadly described as ‘rapid shutdown’ technologies), but all of these options operate downstream of the panels and do not isolate the power produced by the panel itself.

An Australian innovation, PVSTOP, has recently been developed and is now used by a growing number of local and international fire and emergency services agencies to safely isolate the power produced by solar PV systems. PVSTOP acts as a ‘liquid tarp’ that can be sprayed on to solar panels to block light, forming a waterproof film which isolates the power produced by the system in seconds and eliminates the risk of high voltage DC electrocution. It has been independently tested and verified as effective in reducing DC current to safe levels with as little as 40% coverage across the solar panels, it is also non-toxic, environmentally safe and post-incident, it can simply be peeled off the solar panels without causing any damage to the system.

Having undergone comprehensive testing, accreditation, and operational trials in a number of countries, PVSTOP is now standard equipment with a number of the world’s largest and most innovative Fire Departments including the London Fire Brigade (LFB), the New York Fire Department (FDNY), and the Singapore Civil Defence Force (SCDF). This innovation is just one example of the industry’s step toward adapting to more environmentally friendly practices and products that do not limit our ability to embrace clean energy solutions. When carried on first response appliances, it can mitigate DC electrical risk from solar systems allowing for offensive firefighting operations to continue rather than incident commanders having to revert to more defensive strategies.

Learning from the lessons of the past

Solar PV systems are no longer an emerging technology, they are a mainstream energy source and recent history shows us that safety is lagging well behind the exponential growth of the industry. Critical to improving this situation is better statistical data/reporting, better education and training, and new tools that have been specifically designed to mitigate the risks associated with solar PV technology.

Energy storage systems, electric vehicles, EV charging stations, and built-in photovoltaics represent the latest developments in new technology, a technology which is upon us now. They represent a new and exciting industrial revolution, but they also represent significant safety risks for first responders, system owners and maintainers, and broader society.

The future requires effective leadership that is innovative, forward thinking and can navigate bureaucracy to reach effective strategic outcomes. If we focus on effective safety objectives, the future will be bright, clean, and safe, but if we continue to operate in the status quo, history will repeat and we will continue to walk head-long into unanticipated risks.

Fire & Risk Management is the UK’s market leading fire safety journal, published 10 times a year, and is available exclusively to FPA members in digital and print format depending on your requirements. You can find out more about our membership scheme here.

Jim Foran is the Director and CEO of PVSTOP International Pty Ltd.

Solar panel fires on the rise leading to fire safety worries

PUBLISHED
21 September 2023

AUTHOR
FPA Media

SHARE
 

Solar panel fires on the rise leading to fire safety worries

An exclusive report from The Independent has revealed that the number of solar panel fires has risen sharply in 2023 compared to previous years, leading to mounting concern among fire safety experts.

The data, acquired by the newspaper under freedom of information rules, showed that 66 fires related to solar panels had occurred since the beginning of 2023 up to July. This is a stark increase when compared to 63 fires for the whole of 2019. It was also found that there were “six times the number of fires involving solar panels last year compared with 10 years ago”.

Experts have warned that while the rising number of solar panel-related fires reflects the growing reliance on solar panels as an energy source amidst the cost-of-living crisis, it also highlights the limited regulation around them. As previously reported by the FPA, at the end of last year (November 2022), insurance company Zurich UK issued a caution to homeowners who had invested in solar panels to only use installers who were part of accredited schemes. It even called on the government to introduce a single accreditation scheme to counter the current lack of regulation. At the time, the Major Loss Manager for Zurich, Gillian Perry said: “We’re seeing a small but growing number of claims for solar panels, the most worrying of which are electrical fires.

While the vast majority of installers follow good practice, poorly or incorrectly fitted solar panels can increase the risk of blazes.

On 18 September 2023, a major fire related to solar panels broke out at a bungalow in Anglesey. Firefighters from the North Wales Fire and Rescue Service attended the property fire, which is part of an independent living complex run by Clwyd Alyn Housing, and later confirmed it had been caused by an electrical fault. As reported by North Wales Live, a solar panel and batteries were gutted in the blaze. Head of Technical, Innovation and Climate at Clwyd Alyn, Tom Boome said: “Everyone at the property is safe and we apologise for the worry and inconvenience caused. We believe this is an isolated incident, but as a precaution we have disconnected the batteries in all the homes at Min Yr Afon, while we work with partners to establish the facts.”

Another fire broke out at a council house in West London in August after a solar panel exploded on the roof. As reported by the Evening Standard, 25 firefighters spent two hours disabling the solar panels to avoid being electrocuted before they could extinguish the fire’s source. A spokesperson for the London Fire Brigade explained:

PVStop, which is a black liquid polymer coating designed to cover solar panels like a liquid tarpaulin, was used to isolate power to ten solar panels.

It works by blocking the sunlight that powers solar panels, so the process of converting light into electricity is stopped. The panels are then de-energised, and the risk of electrocution is greatly reduced so crews can get closer and prevent fire spreading from a roof to the rest of the building.”

Echoing the guidance of other industry sectors, Martyn Allen from Electrical Safety First said that homeowners should look for registered installers of solar PV panels, stating that this would “provide a better guarantee of safety and also redress, in the unlikely event of something going wrong”.

We also need clarity of electrical safety legislation to ensure that solar photovoltaic (PV) installations are an integral part of obligatory regular inspection and testing,” he added.

PVSTOP: revolutionizing solar panel fire safety

Solar power has emerged as a critical renewable energy source, but commercial-scale solar arrays face a little-known fire risk with potentially major financial and environmental impacts. Innovations like PVSTOP seek to make the solar industry safer by containing and suppressing fires that erupt in solar panel systems. This emerging technology promises huge benefits for insurers and owners of large-scale solar PV Systems.

The solar fire challenge

Most people don’t realize that solar panels can literally catch on fire. However, electrical shorts, damaged wiring and extreme weather can all ignite fires within solar arrays on rooftops or in solar farms. These fires spread rapidly, fuelled by the endless DC electricity flowing from solar cells into conductive wiring running throughout the structural mounts.

The results of a solar fire can be devastating. Hundreds of panels worth over a million dollars can be destroyed in minutes. Toxic smoke and run-off from melted plastics and metals contaminates entire sites. Add to this the loss of clean power generation capacity and the financial toll is massive. Insurers are also starting to recognize the extreme risks that solar system fires pose due to the scale of potential damages for commercial installations.

Yet fighting fires within solar panel arrays poses a unique challenge for firefighters. Electrocution hazards from damaged live wiring can prevent spraying water or foam directly onto burning panels. Fires tucked within racks of panels can hide and evade suppression. And systemic issues trigger panel re-ignition even after apparent extinction.

The PVSTOP solution

PVSTOP provides a simple but highly effective innovation to contain, control and mitigate fires within solar panel installations of any size. The product is an advanced polymer film technology that features proprietary chemistry. When deployed over solar panels, PVSTOP immediately blocks light and de-energises the PV system at the source of power production. The film also dissipates heat while sealing electrical components underneath, preventing re-ignition.

For commercial solar array owners, PVSTOP promises three essential benefits:

  1. Quick containment of incidents to minimize solar asset loss.
  2. Reduced clean-up, replacement and environmental remediation costs.
  3. Prevention of major revenue losses by restoring operation faster.

Insurers also benefit by mitigating massive claim pay-outs to commercial solar power customers in the event of fire-related system damages.

Rapid solar fire suppression

A key capability of PVSTOP is delivering extremely fast solar PV system de-energisation. The lightweight polymer film can encapsulate vast sections of solar panels literally within seconds. This blocks the light, dissipates heat and electrical arcing and prevents wider escalation of an incident. Superior rapid response drastically reduces asset losses compared to traditional firefighting tactics.

PVSTOP’s rapid deployment is the key to limiting damages. The polymer coating can be quickly discharged from portable pressure cylinders stored on-site and sprayed over entire rows of solar panels by technicians in a matter of seconds. Other traditional solutions such as fire extinguishers, or mechanical shut-offs simply cannot deliver the same speed and coverage of PVSTOP extinguishment, and none effectively mitigate the electrical risk at the source of power production. Many of these approaches still leave behind badly damaged panels which pose an ongoing secondary fire hazard until the damaged panels are removed and replaced.

Enhancing PVSTOP with early detection

The ultra-fast fire-suppression capability of PVSTOP can be further enhanced by pairing it with solar panel fire-detection innovations. New sensor systems can identify hotspots and electrical anomalies in solar arrays before visible flames erupt. This early warning allows PVSTOP deployment to start even sooner after an ignition incident begins.

One example is infrared monitoring technology that uses cameras to identify heat build-up indicative of smouldering, before smoking or fire breaks out. Other solutions focus on monitoring DC string voltages to detect anomalies that may signal arcing, shorting or ground faults. Incorporating these early alert abilities with PVSTOP provides the maximum possible jump on containment, drastically reducing damage and replacement needs.

Significant damage to commercial, industrial and utility-scale solar assets could be spared by combining early detection with PVSTOP suppression within 3–5 minutes of the initial failure detection. This would represent an enormous benefit over traditional firefighting that cannot safely access live electrical components buried within panel racks until much later in an event. Early warning detection therefore enhances PVSTOP effectiveness and return on investment for solar system owners.

Maximum solar operation continuity

For owners of commercial-scale solar operations like farms or roof-based arrays, continuity of power generation is essential for profitability. PVSTOP delivers major advantage over alternatives by enabling restored system operation in hours or days – not weeks. The film encapsulation rapidly arrests solar panel electrical risk and destruction, so many panels can be reused once the root cause of ignition is addressed. This prevents immense profit losses from extended solar grid shutdowns.

Additionally, PVSTOP suppresses the propagation of solar fires without causing collateral water or chemical damage throughout the installation. This further maximizes reuse of existing solar infrastructure. Some other fire containment tactics like deluge systems or chemical extinguishers make restoring operation more complex due to contamination or soak-through damage to underlying buildings and equipment. The targeted, clean encapsulation approach of PVSTOP keeps unwanted secondary effects to a minimum.

Lower replacement and remediation costs

Even with fire coverage, many commercial solar panel assets end up being complete write-offs after suffering fire, smoke or chemical damage due to the intricacy of the electrical components and precision structural mounts. But PVSTOP radically reduces complete solar asset losses by arresting the spread of flames before entire sections are engulfed. Salvaging even 30–50% of an affected commercial solar power system saves owners immense expense replacing panels, inverters, racking systems and other supporting infrastructure.

Additionally, containing solar PV incidents with PVSTOP prevents massive environmental clean-up bills down the road. Run-off from water or chemical suppressants can contaminate sites for months, accruing major remediation costs. Melted panel components also create toxic waste. Preventing flames from melting through entire solar panel sections minimizes hazardous by-products that must be disposed of properly. And isolating smoke exposure helps avoid soil disturbances or plant die-offs near solar installations. Overall, the damage control PVSTOP facilitates greatly reduces total costs beyond just panel replacement.

Costs of solar fire pollution

While containment clearly reduces direct solar asset losses, limiting the spread of smoke and run-off from solar fires also prevents massive collateral environmental damages. For example, in 2021 a fire at Europe’s largest solar park in the Netherlands contaminated agricultural lands costing millions of euros.

The blaze filled the air with toxic smoke containing dangerous levels of cadmium and lead from melted solar panels. This smoke plume then rained down particles over thousands of acres of nearby cropland and greenhouses. Testing revealed heavy metal concentrations exceeding safe limits, forcing costly disposal of crops and quarantining of grazing lands.

Estimates indicated remediation expenses over €120 million including disposal of 30,000 tons of contaminated plant material, cleaning of fields, and revenue losses for affected farmers. Meanwhile, in Germany, studies have found solar farm fire run-off has triggered extensive contamination of rivers and groundwater with effects still emerging.

With large-scale solar expanding worldwide, more uncontrolled fires could inflict heavy environmental and economic damages like those observed in the Netherlands and Germany. But solutions like PVSTOP that quickly contain solar fires and toxic emissions offer a pathway to prevent these massive collateral impacts.

Insurer perspectives

Major insurance providers have already acknowledged the immense risk solar panel fires now pose at commercial scales. In 2021, losses from U.S. solar fires exceeded $25 million across more than 85 large claims, catching the industry off guard. Swiss Re and others are rapidly adapting coverage terms in response while premiums are expected to rise sharply. But PVSTOP offers a pathway to control losses with this emerging renewable energy peril.

Insurers stand to benefit tremendously from PVSTOP driving down the costs and occurrence frequency of commercial solar fires. Containing rapid site losses better protects insurance reserves while helping avoid untenable premium increases that could choke the solar industry. And the technology unlocks options for new product offerings like PVSTOP deployment discounts which incentivize proactive solar asset fire safety. Overall, supporting innovations like PVSTOP promises to stabilize renewable energy insurance markets through improved fire-control outcomes.

Conclusion

Solar power delivers immense environmental and economic benefits as an emissions-free energy solution. However, realizing the promise of commercial-scale solar requires controlling largely unknown fire risks that can inflict severe financial and operational damages. PVSTOP represents an exciting advancement that perfectly matches the fire challenge faced by the solar industry today. Rapid encapsulation of burning panel sections promises to revolutionize mitigation capabilities for insurers and owners alike. As PVSTOP adoption spreads, solar power can continue flourishing as an essential sustainable energy source for our future.