Solar electric panels - PN839 Flashcards
Any mistakes or suggestions, please contact Phil Simpson
Solar electric panels
What en-route considerations should a IC be making to a potenetial incident involving solar electric panels?
- Ensure all crews are rigged in full PPE.
- Gather all available information including the use of MDTs.
- Brief crews as to the nature and extent of the risks associated with solar panels if they are known or suspected to be involved
Solar electric panels
What on arrival tactics should be considered at potential incidents involving solar electric panels?
- Attend main entrance or RVP , liaise with the responsible person/owner occupier.
- Confirm the nature of the incident, carry out DRA and apply DMM to assist in formulating a tactical plan to resolve the incident.
- Carry out 360 PV (panels may not be visible from ground consider aerial aplince as observation tower)
- For commercial, industrial or solar farms, obtain site specific plans to determine the location of the inverter and ascertain the voltage or current being produced.
- Consider early request for an authorised person from the relevant power generating/distribution company and system installer for advice
- Ensure that crews are aware that failure to isolate the direct current inverter, may mean that the power to the building is still energised even when the Mains fuse has been removed by the authorised person.
- Consider defensive firefighting until power is confirmed isolated.
Solar electric panels
What is the operational procedure for dealing with incidents involving PV panels?
- Maintain safety (inner cordon) and default to defensive fire fighting operations if panels are involved
- Make sure that the mains power has been isolated, and the solar isolation switch is off.
- If the roof has burned through and the panels have fallen into the structure, unless the panels have been destroyed (de-energized) by the fire and/or falling into the structure, they can still have the potential to be LIVE, they MUST be treated as LIVE.
- When firefighting in structures that may have energized PV systems, the issue of whether or not to apply water is an important tactical decision. If possible, do not apply water directly onto any solar panels affected or involved in fire
- If water is used to this must be applied indirectly to extinguish the fire. Indirect spraying of water means not using a jet and playing the water over the surface rather than directing the water directly onto the panels.
- The spray pattern must be used to eliminate the possibility of electricity flowing upstream.
Solar electric panels
What additional safety measures should an IC consider?
- Safety officers
- Aerial appliances (as observation platforms)
- Full PPE
- Electrical gloves
- BA
- Requesting a HMEPO
- Implementing Line ops
Solar electric panels
What are the potential hazards associated with incidents involving solar panels?
- Electrical
- Working at height.
- Structural roof collapse.
- Inhalation
- Failure of fittings causing panels to fall from roof.
- Hazardous materials.
- Sharps.
- Steam/Hot pressurised water from hot water systems.
- Confined spaces.
Solar electric panels
What actions should you consider, if you discover a premises with solar electricty panels?
Watch officers should assess the hazards identified for a premises or location and determine the level of risk by reference to factors such as size, complexity and layout. The contents, any processes carried out and occupancy should also be considered and the premises must be included within the operational risk database (ORD) as the premises risk assessment score dictates.
Solar electric panels
Where would you expect to find PV cells?
Panels are usually fitted to roofs in order to harvest sunlight where buildings are situated closely to one another. In open spaces with fewer buildings to provide shade, they can be installed at ground level
Solar electric panels
What type of electricty can PV cells produce?
The electrical current produced can be at high voltages in excess of 1000v DC
Solar electric panels
Where would you expect to find the isolator/inverter switch for PV panels?
The inverter’s location is key as it will provide a switch to isolate power to any outlets it is connected to. Installers typically use short runs of DC cable and therefore the isolator will often be found in loft spaces
Solar electric panels
What problem can be encountered when attempting to isolate PV cells during the day?
With a standard multi- panel installation during daylight, there is no practical way of isolating the panels from producing DC current. Tests carried out during strong sunlight , demonstrated that panels covered by a heavy tarpaulin will only reduce but not cut their power output.
Scene lighting or bright moonlight may also enable electricity generation.
Solar electric panels
What is the typical make up for solar hot water heaters?
Consist of panels which are more bulky in appearance. They contain a series of continuous pipe runs carrying water laid into the panel. The water is heated by being exposed to sunlight, which is transferred by pipework to a hot water cylinder. A boiler tops up this stored heat to reach a temperature set on the cylinder thermostat.
Solar electric panels
What is the typical make up for a solar electric panel installation ?
Typically an installation consists of PV cells fixed to a backing board in an alluminium frame weatherproofed by a final laminated glass pane, collectively known as a panel. A series of panels connected together is known a string, with one or more strings known as an array.
Solar electric panels
What are the electrical hazards associated with PV cells?
- Inverters isolate power to the consumer supply by turning a switch, however the DC wiring from panel to inverter will still be live.
- Even covering the modules with a heavy salvage sheet or tarpaulin will only reduce the amount of electricity produced.
- Direct current for these systems is not earthed and therefore if firefighters working very closely to the DC wiring complete an earth circuit they will receive an electric shock
- Arcing presents a risk to firefighters as the light produced is extremely intense and can cause temporary sight impairment.
Solar electric panels
What working at height hazards are there when dealing with solar panels?
- Falling panels : The locking mechanism of the cable connectors ensures individual panels remain connected to each other, however if the cable between the connectors becomes severed there is a danger of solar panels falling from their mountings if fixings fail in a fire. Panels may also fall due to roof structures failing below them, poor standards of installation or maintenance and the age of the system.
- Glass and glass fragments: Panels damaged by extreme heat may cause glass tubes or surface glass to fracture or explode and fall or ‘plane’ from the roof .
Solar electric panels
What are the inhalation hazards associated with solar panels?
As well as the normal products of combustion associated with a building fire, during a fire or explosion the PV frame can quickly degrade spreading hazardous chemicals within the smoke plume. all of which are toxic and/or carcinogenic
(However the amounts of these chemicals are extremely low and some will be destroyed by fire. If modules are undamaged the chemicals will be retained)
Solar electric panels
What battery hazards are associated with solar panels?
In some installations the excess energy produced is stored in batteries. If batteries are exposed to fire the fumes produced are extremely toxic and corrosive. Spilled electrolyte from the batteries can react and produce toxic fumes and release flammable and explosive gases when it comes into contact with other metals. Leaking batteries may cause a chemical hazard to attending personnel
Solar electric panels
If solar panels are directly involved in a fire, how should they be regarded/treated ?
Do not apply directly onto panels, cordon off and default to defensive tactics.
They should always be considered to be live and capable of generating electricity. Unless completely destroyed by fire or dismantled/made safe by a specialist installer
Solar electric panels
If you are unsure or unable to isolate the invertor/isolator, what should you consider?
The system isolation switch maybe located either on the main fuse board/consumer unit or near the inverter, If both the main fuse and consumer unit are isolated there will still be live current from the panels to the inverter which will also need to be made safe. An immediate request for the attendance of Electrical Authority or specialist installer for further guidance should be made
Solar electric panels
If fire has broken through roof materials, how it is possible to minimise the risk of electric shock when applying water?
By applying water in spray form and by allowing the water from a jet to arc and fall down onto the area on fire.
Solar electric panels
What is a module ?
Typically, a module consists of PV cells fixed to backing boards in an aluminium frame, weatherproofed by a glass pane
Solar electric panels
What is an array ?
One or more ‘strings’ are known as an array
Solar electric panels
There are 2 types of solar hot water system, what are they called ?
Evacuated tubes
Flate plate collectors
Solar electric panels
What are the main components of a PV system?
