Grid connected PV system

Grid connected PV systems are PV systems connected to the public electricity distribution network. These can vary in size from a few kW to very large ground mounted MW installations.

In most cases, the owner of the PV system benefits from a feed-in-tariff which is considerably higher than the cost of the electricity bought from the grid which is generated by conventional means.

The basic elements which constitute a Grid connected PV system are:

• Solar panels. These are usually installed on the roof, and produce the electricity at a DC voltage. The panels are connected together to form an array depending on the system size. Panels are mounted on metal structures which are certified to withstand wind loads.
• The inverter. In a grid connected system, the inverter has the role of converting the variable DC output from the panels to AC current synchronised with the grid. An important feature, also required by law, is the anti-islanding protection which prevents operation in the absence of a grid voltage.
• Connecting cables and switchgear. The above equipment has to be connected with the right type of cable to avoid degradation during its lifetime due to load currents or environmental exposure such as UV radiation. Protective devices are also installed to provide isolation and protection in the event of failure.

For domestic use, the choice of a system size depends on the energy consumption pattern of the household and the site conditions of the residence, for example, shading problems. The selection process is an important step to help the client maximise on his return on his investment within the potentials offered by the premises. Free on site consultation is offered by us at this stage. All equipment is approved by the Regulator for Energy & Water Services (REWS) and qualifies for government grants. Our clients are assisted in all the documentation needed throughout the process from the initial grant application to the final Enemalta application to connect the photovoltaic system to the grid. In the majority of cases, we have found that local households can be serviced by one of the following options. As to prices, these are regularly being updated, so please feel free to contact us for a quotation. Moreover, for any other configuration, we are here to assist.

Grid connected system are also used for commercial and industrial applications, in which case, the design is usually based on using 3 phase inverters. We can cater for any system size, however, for 3 phase systems larger than 10kW ac, an authorisation from REWS is needed which requires clearance letters from both Enemalta and MEPA.  Smaller systems require a simple notification process with REWS.  Please contact us for more information on 3 Phase systems.