Safety in photovoltaic systems – before, during and after installation

Safety is a fundamental aspect that must be taken into account when setting up and operating any renewable energy installation. Measures must be taken to ensure both the integrity of the materials to be handled and the safety of all personnel involved in the installation. Furthermore, these measures must be considered at all points in the life of the installation: during storage and transport of the components, during assembly and later during operation, and during any maintenance work.

Before assembly

The first step is to avoid possible damage during transport and storage of the materials. It is important that, during the pre-assembly phase of the installation, the components are stored correctly and treated appropriately: ensure that all elements are stored in their original packaging; photovoltaic panels should be stacked to prevent them from falling or being scratched; liquid electrolyte batteries should always be placed vertically; bulky elements such as inverters and batteries should be placed in such a way that there is no risk of falling, knocks or scratches, etc.

On the other hand, some safety aspects must also be taken into consideration in the project engineering. When designing the installation, it is important to leave clear spaces between rows of PV modules to allow for the passage of operators. This will facilitate assembly and maintenance. The rest of the equipment (inverter, batteries, etc.) should be located in a properly ventilated room.

During installation

The safety regulations for the installation of a photovoltaic system must be taken into account in accordance with the Occupational Health and Safety Regulations. The aim is to ensure the safety of people and not to damage the materials.

It is compulsory and essential that during installation, the team in charge of carrying out the installation has the necessary safety systems (Personal Protective Equipment or PPE, lifeline, harness…). Otherwise, their own lives and the integrity of the physical spaces where they are working and of the equipment and components being handled may be put at risk.

Proper handling of fragile and delicate elements, such as solar panels, and heavy components, such as some inverters and batteries, is key to avoid premature deterioration.

The main problems that can arise on the electrical side are overvoltages, overloads and short circuits. These phenomena cause damage and deterioration in the installation, which can lead to a decrease in performance or even fire. To prevent this, protection elements such as circuit breakers and fuses must be included. Likewise, photovoltaic installations must be grounded: the equipment (protective earth) and any active conductors (system earth).

The non-electrical part refers to the structures, anchorages and other fastening elements of the installation components. These must be suitable for the location and physical characteristics of the project. They must withstand the maximum possible wind load and, if necessary, the maximum snow loads.

Marking of sensitive areas on rooftop with cones

With regard to personal safety during assembly, a number of considerations need to be taken into account:

• If the work is carried out in summer or in direct sunlight, regular breaks should be taken to avoid fatigue, dizziness or dehydration. It is important for the operator to drink water frequently and to have shading equipment available.
• For work at height, such as the installation of panels on roofs, some basic safety rules should be considered:
  • The operator must be attached with a harness to the lifeline or anchorage points to prevent falls. Lifelines can be temporary (set up, used and dismantled according to the needs of the project) or fixed.
  • Use of PPE: helmet to avoid knocks, safety footwear to avoid knocks and slipping, gloves to handle cutting and drilling tools. If necessary, also goggles to avoid glare.
  • When moving on the roof, be careful not to step on fragile areas such as skylights and take care not to trip over the panel anchors. In the event of rain, it is not advisable to climb onto the roof, as it is slippery and there may be a greater risk of falling.
  • It seems like common sense, but it is necessary to remember: do not walk on top of the panels. Micro-cracking of the cells can occur which, although not visible to the naked eye because the tempered glass of the panel does not break, can cause hot spot problems.
• A personal safety voltage level of 48 V must be set as a general rule for both direct and alternating voltage. In circuits with a voltage higher than the safety voltage, one active conductor must not be handled as long as the other active conductor is accessible and unprotected.

In any case, teamwork is essential: it is easier to avoid an accident with colleagues who are committed to safety.

During operation of the installation

Once the installation is commissioned for normal operation, the risk areas must be suitably signposted. Access to the inverter and battery room shall be restricted to those persons authorised to handle them.

Prevention must always take precedence over any other type of safety. To avoid running risks that could lead to problems, it is important to contact professional photovoltaic installers who know how to handle materials properly and who work in accordance with safety regulations.