London firefighters used a new glue like liquid to save a school in Twickenham from burning down and they are the first crews in Europe to use this unique scientific breakthrough.
Crews were called to a fire at a school in Hampton Road in Twickenham and the specialist glutinous gear called PVStop prevented serious damage to the roof of the building by preventing the fire spreading to the solar panels.
PVStop is a black liquid coating designed to cover solar panels, like a liquid tarpaulin, which is sprayed onto the panel using an extinguisher or from the head of an aerial appliance.
Operational Policy Watch Manager George Mahoney said: “The fire started in an extractor fan on the ground floor and spread into the void of the roof, where the school had solar panels. Without crews quickly applying PVStop, the fire could have very quickly spread to the solar panels which in turn could have compromised the roof of the school.
“Incidents involving solar panels can be especially dangerous as it’s difficult to isolate the electrical current they generate if they are damaged or involved in a fire and PVStop works by blocking the sunlight which powers them so the process of converting light into electricity is stopped.
“Science and quick thinking of firefighters really saved this school”
“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.
”A combination of science and the quick thinking of firefighters really saved this school from significant damage.”
Part of the ground floor toilet area in the two-storey school building and part of the roof were damaged by the fire, but damage to the solar panels was prevented by the use of the liquid.
The liquid, which is environmentally friendly and non-toxic, has been distributed to eleven of the Brigade’s aerial appliances.
Operational Policy Watch Manager George Mahoney continued: “This is the first time PVStop has been used operationally in Europe. It has been used once in Australia, where it is manufactured.
“It was great to see this in action for the first time and it was successful – it prevented the fire spreading and has saved the school the cost of having to replace the solar panels.
“We had spoken to crews about PVStop just this week as with the heatwave we had been expecting it.”
The Brigade was called to the fire at 1308 on Thursday (19 July) and the fire was under control at 1528. Four fire engines and around 25 firefighters from Twickenham, Southall and Richmond fire stations attended the scene.
Around 40 pupils and 15 members of staff left the building before the Brigade arrived. There were no reports of any injuries.
The Brigade’s Fire Investigators believe the cause of the fire was an electrical fault in an extractor fan.
In Part 1 of this article featured in the last edition we discussed the rise of solar energy from a cottage industry just a few decades ago to becoming a genuine mainstream electrical source. We discussed how legislation, safety and fire training have failed to keep up with the rapid expansion of this alternative energy source. We then moved on to discuss training objectives and offered some basic education in the differences between AC and DC electricity, how solar PV panels work, the different types of solar PV systems and finally the upcoming battery storage revolution.
With this foundation of knowledge in place we will now move on to discuss what goes wrong with solar PV systems, the dangers faced by fire and emergency services personnel, discuss the recent attempts to make solar PV systems safer and introduce you to a new product which offers a simple solution to this growing and complicated problem.
How Do Solar PV Systems Fail?
There are a number of reason why PV solar systems fail, ranging from physical damage and component failure to poor manufacture and workmanship.
Physical Damage
Physical damage to solar PV systems can be due to a number of factors. Weather events such as hail, lightening, fire, storm damage (such as fallen branches) flooding and water ingression are all well document causes of system damage. Vermin attack such as chewed wiring and nesting are other less considered causes of system damage. It is also worth noting that even when a solar PV system is seriously damaged, broken, shattered, burnt or inundated with water, it can still produce potentially lethal amounts of DC electricity.
Component Failure
In Australia hundreds of solar PV system failures (and fires) have been caused by faulty DC isolation switches. It must also be remembered that solar PV systems are comprised of delicate electronic componentry that generates electricity. When mounted on roofs and exposed to constant UV and both freezing and boiling hot conditions, 365 days a year, over time they will naturally deteriorate. As such solar PV systems should be periodically checked and maintained. However because of the installation location of most solar PV systems (on roofs) they are out of sight and out of mind; very few systems are maintained regularly or adequately. Finally, the vast majority of solar PV systems are relatively new (less than 10 years old). As these systems age, the number of incidents relating to component failure will escalate on an increasing scale.
Poor Manufacture & Workmanship
In the year 2000 there were 8 companies producing solar panels globally. In 2005 there were 20 companies producing solar panels globally. In 2007 there were 846 companies producing solar panels in China alone! Expertise is not earned overnight and one of the challenges of the exponential expansion of solar technology over the past decade has been a shortage of skilled labour, both on the manufacturing and installation sides of the industry. Without adequate legislation or regulation to keep abreast of growth, there are a large number of solar PV system installations that are sub-standard and a lesser number that should be considered unsafe or dangerous. Neither governments nor industry sources are properly equipped to manage or audit the existing and growing number of solar PV system installations and it has fallen upon fire and emergency services agencies to reactively manage and mitigate these risks as they are encountered.
The DC Danger Zone
As discussed earlier, as long as solar panels are exposed to light, they cannot be turned off and like any electrical generator or source that is live, must be considered dangerous. Even with an isolation switch installed at the solar PV system inverter, the solar panels on the roof and the electrical wiring leading down to the inverter and completely live and producing potentially lethal amounts of DC electricity. In professional terms this is known as the “DC Danger Zone”.
Unlike traditional sources of electricity solar PV systems cannot be switched off or isolated effectively. If the panels or wiring leading to the inverter are faulty and arcing, the solar panel frame, metal roof or metal guttering all have the potential to be conducting lethal amounts of electricity that can ignite fires or electrocute unsuspecting emergency services personnel, electrical technicians or the general public if they come into contact with a conductor (via a ladder or unbroken stream of water etc). Up until now there has not been an emergency response protocol or strategy that has adequately mitigated these threats.
Recent Rules, Regulations and Technologies
In recent times Governments and Industry have attempted to address the issues surrounding the DC Danger Zone with limited success.
DC Isolators
In Australia, roof top isolators are a legislated requirement. They were implemented with the intention of turning the panels off in the event of a short circuit or similar emergency. Although well intentioned, switching is an AC electricity solution and is not suitable for DC electrical applications. Every time DC is switched, it arcs on the circuit board and has the potential to set the switch alight. Since legislation was passed in 2011, there have been hundreds of solar PV related fires in Australia as a direct result of faulty isolation switches and literally tens of thousands of DC isolations switches have been recalled as a consequence of these incidents. Isolation switches on solar PV arrays is a bad idea and has created more problems than it has solved. This legislation seems set to be reversed in the near future.
Anti Arcing Equipment
In a further attempt to improve safety, Standards have now incorporated anti arcing devices in all newly installed inverters. This standard solves one problem in that it shuts down the inverter and disconnects the load from the solar panels, allowing the panel wiring to enter into open circuit voltage, extinguishing any “series arcing” occurring. But in the case of a parallel arcing fault, it can allow the full amount of the power available to be poured into the fault, fuelling the arc and making the arcing fault much worse!
The Red Zone Above Indicates the DC Danger Zone.
Rapid Shutdown/Micro-inverter Panels
Micro-inverters are a hot topic, especially in the United States where there has been a legislative push to make micro-inverter solar PV panels the standard (over string panels). Micro-inverter solar PV panels are being marketed as a safer alternative to string array solar PV panels as a small (micro) inverter is installed directly underneath each individual panel, converting the DC electricity to AC electricity directly under panel and allowing electricity to be shut down directly below the panel. Note however that the panel itself can still not be shut down when exposed to light and still has the potential to arc potentially lethal DC voltage directly onto the panel frame, metal roof and guttering.
This is not a new technology, micro-inverter panels have been around for over 20 years. Apart from the perceived safety improvement versus string array panels, micro-inverter panels also have the advantage of having better shade tolerant properties than string array panels. The disadvantages of micro-inverter solar PV panels is that they are very expensive, up to three times the cost of a standard string array solar PV panel. Also, inverters are sensitive and delicate electronic components and do not like heat. This is why standard inverters are generally installed inside garages or on the shady sides of properties. By miniaturizing the inverter and installing them directly onto the back of each solar panel, micro-inverters are being exposed directly to the elements and high operating temperatures. As a result, the life expectancy of micro-inverter solar PV panels is greatly reduced versus standard string array solar PV panels.
Finally, we have noticed recently that in order to reduce the price of micro-inverter solar PV systems, manufacturers have started designing “micro-inverter” systems with 1 inverter to every 2 panels and even 1 inverter to every 4 panels. In essence these are now micro-string arrays rather than true 1 to 1 micro-inverter arrays. Micro-inverters are another step towards improved solar PV system safety, however they are not financially viable for most applications, are prone to failure and because of the prohibitive cost are now being watered down to a less than ideal solution.
Mitigating the dangers of the DC Danger Zone
With over 40 years of experience in the solar industry, The Australian Company Solar Developments recognised the need to find a simple, fast and economical solution to tackle the broad and complex risks associated with the DC danger zone. A solution that isolated the power at the source (the solar panel surface) thus eliminating all the complexities in the downstream componentry. The result of this search is PVStop, a global innovation developed by Luke Williams, one of the founding directors of Solar Developments and the inventor of PVStop. Luke is a CEC (Clean Energy Council) accredited renewable energy system designer and has been working in the Australian solar industry since the early 1970’s.
How does PVStop work?
PVStop is a state-of-the-art polymer film technology. Delivered from a pressurised cylinder similar to a fire extinguisher, it acts as a “liquid tarp” covering the solar panel surface and switching off the solar PV system in seconds, rendering the entire solar PV system safe.
With a delivery range of over 10 meters the product can be applied from the ground or from an elevated platform, eliminating the need to climb on to rooftops and operate at height. It can be utilised in all weather conditions and is touch dry within a matter of minutes, creating a waterproof coating that insulates the solar panels and protecting the panels from fire, heat and impact damage. The coating is also non-flammable and fire retardent and is capable of extinguishing the panels if they are on fire. In addition, the coating is non-conductive and anti-arcing, which is essential as its primary function is to isolate the power generated by solar PV systems. The coating also encases any nano-particles released in the event that the panels are damaged or during salvage operations. At the completion of an incident, the dry coating can simply be peeled off the solar panels like a latex sheet without causing any damage to the solar PV system or surrounding structure. The coating is non-carcinogenic, can be safely handled and disposed of with normal garbage waste
Reducing risk factors for emergency services and electrical technicians
The exponential growth of the solar industry has led to a commensurate rise in the number of solar system incidents encountered by fire and emergency services agencies. Ten years ago fire and emergency services agencies rarely encountered incidents involving solar PV systems; today incidents involving solar PV systems are encountered on a weekly basis. As the only safe, fast and reliable solution to isolating the power produced by solar PV systems, PVStop has rapidly come to the attention of fire and emergency services organisations both in Australia and abroad and is currently undergoing testing and review by a number of these services.
The broader picture around solar safety.
Products such as PVStop are only one component of the much broader solution required around solar energy and battery storage. Fire and emergency services require new and innovative training resources and fast adoption of new procedures as new products become available to solve new problems. New legislation is also needed to remove the responsibility wholly from fire and emergency services and place more onus on industry and system owners to install systems with more integrated safety solutions. The solar battery storage revolution is just getting started as is the wide adoption of electric vehicles and their integrated battery storage systems. These are the next challenges that are faced by the fire and emergency services industry, but that’s a topic for another article!
The growth of solar photovoltaic (PV) systems has been exponential for the past two decades. In the last 10 years especially, the world has seen solar PV evolve from a pure niche market of small scale applications towards becoming a genuine mainstream electricity source.
This has been driven by a number of factors. When solar photovoltaic (PV) systems were first recognized as a promising renewable energy technology, governments started implementing programs such as feed-in tariffs to provide economic incentives to invest in solar projects. As a consequence, cost of solar declined due to improvements in technology and economies of scale, even more so when widespread production ramped up in China. Another factor has been the rising cost of grid electricity in first world countries and the lack of reliable grid electricity in third world countries. In conjunction with these trends, popular sentiment has shifted towards finding clean, sustainable and affordable energy sources for the future wellbeing of the planet.
Deployment of photovoltaics will continue to gain momentum on a global scale and solar PV is set to become an increasingly popular competitor to conventional energy sources. In fact, grid parity has now been reached in around 30 countries with predictions that 80% of countries will be at parity by the end of 2017. To quantify this in numerical terms, cumulative PV power capacity is nearing 200GW (gigawatts) which is the equivalent of nearly 1 billion solar panels installed globally. A figure that is forecast to reach 2.5 billion solar panels by the end of 2017.
Legislation, safety and training
Due to the exponential growth of the solar industry globally and its rapidly evolving technology, standards and legislation have not been able to keep pace with solar innovation. There are very few true experts in this new frontier and it is becoming increasingly obvious that there is a significant gap in the safety protocols surrounding the use of solar. There is an urgent need for better training programs to educate the various industries that are impacted by the increasing popularity of solar.
The knowledge gap
Firefighter awareness of solar PV systems, being able to identify the different types of solar PV systems and gaining a basic operating knowledge of these systems are paramount to effectively mitigating a fire event involving solar PV systems. Taking this back one step further, it is also essential that firefighters are aware of both Direct Current (DC) electricity and Alternating Current (AC) and the differences between the two electricity types.
Training objectives
Firefighters cannot be expected to be electrical engineers, so a training program needs to be tailored to equip firefighters with the necessary tools to make accurate and informed decisions when dealing with incidents that involve solar PV systems. So what information do firefighters require and what are typical questions that are asked?
Firefighters need to understand the different types of electricity, the nature of DC electricity and how it works in solar PV systems. Why would you want to turn solar systems off? How do you turn one off? What goes wrong with them? How does presence of a solar PV system impact your first response procedure? These are just a few of the questions that need to be answered.
Physiological Effects of DC Electricity Table of the physiological effects of DC electricity taken from the AS/NZ Standard
Understanding the animal
Let’s start with electricity basics; Watts = Volts x Amps. A Watt is a unit of power, this is the indicator of how much power is available (or how badly it can hurt/injure you). Remove either Volts or Amps and you have no Watts (meaning no power/electricity).
Alternating Current (AC) is created by a rotary alternator. Electrons flow and vibrate backwards and forwards creating a frequency. The voltage and frequency varies from country to country, but in most regions the voltage is typically either 220- 240 Volts – AC (220V-240V) or 110 Volts – AC (110V). Frequency is typically 50Hz (50 cycles per second) or 60Hz (60 cycles per second). Because of this positive and negative alternating frequency, if you come into direct contact with the electrical current your muscles will contract and release, potentially allowing you to break free of the electrical current.
Direct Current (DC) is the type of electricity that is generated by all solar PV systems. The electrons only flow in one direction and so do not produce a frequency. Direct Current (DC) travels in one direction only, from the source to the load. Due to this, if you come into direct contact with the electrical current your muscles will contract and lock, there is no opportunity to break free of the electrical current. If you do try to break the load (wire short circuit, switch or even your skin) from the source, the current arcs very badly, either setting fire to or burning the load. From a physiological perspective, given the same voltage and amperage, Direct Current (DC) will not allow you to break contact and will cause much worse deep cell damage than Alternating Current (AC) (excluding high voltage/high amperage equipment which is just plain deadly from either an AC or DC source).
To dispel the myth that voltage alone is dangerous let’s use the example of a Taser. A Taser produces 50,000 volts, but only 0.0021 amps (105 Watts). Once contact with the body occurs the voltage drops, delivering an actual electrical charge to the body of between 7-26 watts. It will incapacitate an adult but causes no long term physiological effects. In contrast a typical domestic solar array will produce anywhere between 4kw (4000 watts) and 6kw (6000 watts) which is lethal.
Solar panels come in a huge variety of sizes and power outputs, anything from 1 watt through to modern panels of up to 315 watts.
A solar panel consists of many individual solar cells joined in series. Each solar cell produces 0.6 volts DC (at 25°c) no matter what size they are. The size of the solar cell determines the amperage that the solar cell produces. The larger the solar cell, the higher the amperage. The output of a typical modern solar panel is 250 watts.
These panels are then joined in series (also referred to as a string) to increase the voltage. Domestic solar panel strings are limited to an output of 600V and industrial/commercial strings are limited to 1000V , this is due to a number of factors such as the high cost of circuit breakers and isolators rated at over 1000W and also due to the potential problems associated with high voltage stress(HVS). Larger commercial and industrial solar PV Systems typically consist of multiple strings run in parallel to increase power output.
Types of solar systems
There are 3 types of solar PV systems. Firefighters need to be able to identify the three types of systems in order to determine the most appropriate risk assessment and isolation procedures (to be discussed in more detail shortly)
Grid Interactive System
A grid interactive system is a solar PV system that is connected to the utility grid. Any excess power that is produced beyond the consumption of the connected load (ie household usage) is fed/sold back to the utility grid. This allows the property owner the ability to earn feed-in tariff credits from the utility grid provider.
Standard net metered grid interactive solar system
Off Grid System
An off grid system is a solar PV system that is not connected to the utility grid. An off grid system requires a number of additional components (compared to a grid interactive system) such as a battery storage system to store excess power, a regulator, a mains disconnect and a generator to support the system if power is depleted from the battery storage system.
Standard dc coupled off grid solar system
Hybrid System
This third (and most recent) solar PV system type provides the best elements of both the grid interactive system and the off grid system. The convenience of a grid connected system, including the ability to earn feed in tariff credits with the extra flexibility of a battery storage system. This means that even during a power blackout, you still have electricity (more on the implications of this later). There is also a growing financial incentive; the ability to store your own power (through the battery storage system) and relying much less on the utility grid. In effect the utility grid adopts the function of the generator in the off grid system. Power from the utility grid is only utilized when power is depleted from the battery storage system.
Standard grid storage/hybrid solar power system
The battery storage revolution
With the “best of both worlds” scenario that hybrid solar PV systems offer, virtually every grid interactive solar PV system currently installed will adopt a battery storage system within the next 5 to 10 years. According to studies by the CSIRO in Australia, it is forecast that up to half of all electricity generated will be on site (homes, businesses and communities) within the next few decades. These battery storage systems (or energy storage systems) will hold the same amount of potential energy as a 44 gallon drum of fuel. They will be mounted within garages next to normal household possessions, next to parked cars (many of which will have similar battery storage systems as well). They will not always be easily accessible and currently there is no legislation around the location, installation or signage of the mains disconnect. The implications for fire and emergency services personnel globally are significant!
In part 2 we will continue on to explain why solar PV systems fail, the DC Danger Zone, recent rules, regulations and technologies, and give you an overview of a new product PVStop which is designed to mitigate the dangers associated with the DC Danger Zone and offer first responders with a solution when encountering incidents involving solar PV systems.
This article first appeared in Fire Australia, Issue 2, 2019.
Photovoltaic (PV) systems, commonly known as solar panels, are a growing challenge for the fire and emergency services. For personnel, this can be responding to a solar panel fire, attending to storm or flood damage or encountering a property that has a faulty or substandard solar system installed. Solar panels pose a serious risk to personnel safety due to their capacity to circulate electricity even when switched off.
Statistical evidence published by the Clean Energy Regulator warns that solar panels represent a serious national safety issue. This is supported by the increasing number of solar panel incidents reported by fire and emergency service agencies through the Australian Incident Reporting System.
Solar panel systems are emerging as a new and growing incident category, yet current standard operating procedures 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.
Working amongst damaged and live solar tiles is potentially fatal. Photo: Fire and Rescue NSW
Sobering statistics
Solar panels have experienced a staggering 5,000% increase in Australia over the past ten years. Approximately 20% of Australian homes now have rooftop solar, and the ever-growing number of commercial, industrial and solar farm installations have seen the number of PV systems across the nation surpass two million.
In December 2018, Federal Energy Minister Angus Taylor made headlines when he warned his state counterparts that lives are at risk from unsafe or substandard solar panel installations. Quoting figures produced by the Clean Energy Regulator, he stated that up to one quarter of all rooftop units inspected posed a severe or high risk. Extrapolated against the current number of two million national rooftop installations, this equates to potentially 500,000 unsafe or substandard installations across Australia.
Solar panels damaged by hail pose a safety risk to fire and emergency service personnel. Photo: Stewart O’Regan
The 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 240-volt AC power outlet is usually rated at ten amps and provides 2,400 watts of power. The average size of a residential solar PV installation is five kilowatts, usually configured in multiple strings of up to 600 volts per string. With up to ten amps available, the average residential solar PV array can produce up to 5,000 watts of power. Residential installations of up to ten kilowatts are now common, while commercial installations can be upward of several hundred kilowatts, and generation plants can exceed 100 megawatts or more.
Tarping solar panels is an outdated and dangerous practice. Photo: Stewart O’Regan
Deadly mistakes
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 knowledge and safety gaps. As a result 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, which state that crews should assume the solar power system and surrounding area is live. Standard operating procedures 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.
The December 2018 Sydney hailstorms highlighted that this dangerous practice is still being utilised as agencies struggle to adapt and come to terms with responding to incidents involving solar panels. Tarping solar panels is an outdated but persistent practice that is done with good intentions but is ultimately a dangerous solution.
Unanticipated risks: fire and ice
Following the same storm event in Sydney, a new and previously unanticipated risk was highlighted when hail damage to solar panels led to secondary fire incidents. One example was in the Sydney suburb of Moorebank, where a factory’s roof top solar panel system had sustained heavy hail damage. Although power had been subsequently isolated, hot and sunny conditions returned and, three days later, the damaged panels began arcing and sparked a significant roof fire that put the entire factory at risk.
There are still many rooftops across Sydney with hail-damaged solar panels. Some owners remain oblivious to the fact that these systems present a significant ongoing fire risk until the solar panels are disconnected and removed.
Hail damage to a solar panel array of a Moorebank, NSW factory sparked a significant roof fire. Photo: Tacca Plastics Pty Ltd
Toxic problem
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. Solar cells contain the carcinogens cadmium telluride and gallium arsenide, as well as the 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.
The full scope of solar panel risk
With solar panels now installed on one in five buildings across the country 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 cause is 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.
Solar solutions
There is currently a range of electro-mechanical solutions available on the market including isolation switches, micro-inverter systems and DC-optimising equipment, but all of these options operate downstream of the panels and do not isolate the power produced by the panel itself. An Australian innovation, PV Stop, has recently been developed and is now used as a reactive solution to safely isolate the power produced by solar PV systems. It acts as a liquid tarp that can be sprayed over solar panels to block light from hitting the panels, which isolates the power produced by the system in seconds and eliminates the risk of high voltage DC electrocution.
A critical consideration for fire and emergency services agencies when adopting a new product is the assurance that the product is safe for their personnel, the community and the environment. PV Stop, which was awarded the FPA Australia’s Innovative Product and Technology Award in 2018, was tested by the NSW Environment Protection Agency for harmful elements and has been deemed safe for the environment and personnel working in the vicinity of solar panels. This 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.
PV Stop eliminates electrocution risk from solar panels. Photo: PV Stop International Pty Ltd
Working toward a cleaner future
As technology continues to evolve at its current rapid rate, it is critical that safety innovations keep pace to ensure the fire and emergency services sector can maintain its commitments to emission reductions and environmental protections, without sacrificing the safety of personnel. Actions during the December 2018 hailstorms in Sydney show the sector needs to do more to adapt to emerging technologies and their associated risks, but proactive fire and emergency service agencies can continue to address these knowledge and resource gaps by seeking information, continually improving their practices and driving the development of innovative new safety technologies.
2020 was a bumper year for solar power in Australia. More solar PV systems were installed in the first nine months than in all of any previous year.
Almost one in four Australian houses now have rooftop solar panels. But the number of solar panel incidents reported by fire and emergency services has increased too.
The exponential growth in solar PV and associated problems has attracted media and political attention.
In 2018, federal Energy Minister Angus Taylor warned his state counterparts lives were at risk from substandard solar panel installations. An audit of the Clean Energy Regulator by the Australian National Audit Office found there were potentially tens of thousands of badly installed and even unsafe rooftop systems. The regulator had inspected just 1.2% of rooftop installations.
It’s a nationwide problem
State and territory regulators are responsible for electrical safety. Only Victoria mandates an inspection of each installed system.
Last October, Fire and Rescue NSW Superintendent Graham Kingland said:
Over the last five years we have seen solar panel related fires increase five-fold. It is not uncommon to see solar panels cause house and building fires.
On Christmas day, ACT Fire & Rescue attended a fire at a home in Theodore where the solar panels caught alight. Coincidentally, the location was Christmas Street!
Components such as DC isolators and inverters, rather than the actual panels, are the cause of most solar-related fires. A DC isolator is a manually operated switch next to a solar panel array that shuts off DC current between the array and the inverter. It was intended as an extra safety mechanism, but the switches have caused more problems than they have solved – particularly when not installed correctly or when poor-quality components are used.
Solar is cheaper in Australia but poorly regulated
A recent report rated Australia as one of the cheapest per kilowatt for solar PV, but it questioned our safety standards. Most solar systems sold in Australia use DC voltages that can pose a serious fire risk.
Unfortunately, Australia has been slow to adopt safer solar regulations. In contrast, the United States has had safety standards preventing the installation of conventional DC solar systems since as early as 2014.
It’s more difficult for lower-voltage, microinverter-based systems (requiring no DC isolator switch) to catch fire, but it’s not impossible.
An amendment to the DC isolator standard (AS/NZS 5033:2014) to improve product datasheets and ensure isolators can withstand the harsh Australian climate took effect on June 28 2019. By then, over 2 million systems had been installed on Australian rooftops.
Added to issues such as flammable cladding, dodgy electrical cable and other “grey imports” (products not sourced from approved manufacturers) in the building industry, we are now playing a game of catch-up.
Poor-quality solar rooftop components have led to an expanding list of product recalls. The latest Australian Competition and Consumer Commission (ACCC) recall list includes installations managed by industry giants such as Origin and AGL.
One notable recall in 2014 reported a risk of “arcing” and “eventual catastrophic failure, resulting in fire”. It listed no fewer than nine traders operating nationally as having used this failed product. The recall noted that the product supplier, Blueline Solar Pty Ltd, was insolvent.
What should consumers do? The ACCC said:
Owners should immediately shut down the PV system following the standard shutdown procedure.
If a consumer suspects they have one of the affected units, they should have an electrician inspect and replace the DC isolators.
Solar systems do not fall under the National Construction Code unless an ancillary structure is being created. Most systems are simply fixed with rails to an existing roof. If the code covered rooftop solar, this would require private certification and a compliance check on any system, as is the case overseas.
Research has shown consumers’ knowledge of solar systems is poor. Many owners have little idea if their system is working properly, or even at all.
And how would a consumer know what kind of DC isolator is on their roof or how to shut down the system in the event of a fire?
Solar panel systems are a growing incident category for firefighters. Yet even among firefighters there is some confusion on procedures to deal with a fire on live solar panels.
Even some firefighters aren’t clear about how to deal with fires on live solar panels. riopatuca/Shutterstock
Solar panel fires have yet to make it onto a top 10 list of domestic fire causes (statistically, your Christmas tree lights are a greater risk). But the sheer volume of installations and ageing components in uninspected older systems are increasing the risks.
One Aussie inventor has developed a product PVStop — “a spray-on solution to mitigate solar panel risks by reducing DC output to safe levels to offer homeowners and emergency personnel peace of mind”.
The latest update on Clean Energy Regulator inspections completed to June 30 2020 shows a negligible 0.05% decrease in substandard systems. Roughly one in 30 systems (3.1%) have been deemed unsafe and another 17.9% substandard.
Without adequate solar PV industry standards, tools, inspection regimes, procedures or training, dangerous scenarios may increasingly put lives at risk. The high uptake of solar is very good news for reducing household electricity bills and carbon emissions, but safety issues undermine these positives.
The surge in installations, the introduction of batteries, the ageing of panels and components together with more extreme weather events mean solar panel incidents are likely to continue increasing.
Australia prides itself on being a world leader in household solar but until now we have not fully appreciated the safety risks. Fire authorities would do well to update fire safety guides that omit specific information on solar. And system owners should ensure they understand the risks and shut-down procedures.
The team at PVStop are very excited and proud to announce that they have won the FPA Australia, Fire Protection Industry Awards in the category of “Innovative Product & Technology for 2018!”
The Innovative Product & Technology Award is a new award category for 2018, so it is an even greater privilege to be the inaugural winner of this new award category.
The award recognises the outstanding contribution from an organization, for the development of leading edge industry products and technology solutions for the purpose of progressing the fire protection industry in Australia and acknowledges the commitment to providing solutions to existing threats / issues, currently facing the fire protection industry and community.
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 effect
DC threshold limit for adult (milliamps)
Mild shock reaction
2 mA
Lock on
40 mA
Electrical burns
70 mA
Ventricular fibrillation
240 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.
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.
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:
Quick containment of incidents to minimize solar asset loss.
Reduced clean-up, replacement and environmental remediation costs.
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.
