How does Solar Energy work?
Each project and each client represent a unique solution. However, they all have one thing in common, which is independent from the system scale: how systems transform solar energy into electrical energy.
Photovoltaic (PV) solar energy is obtained through the transformation of solar energy into electrical energy through a photoelectric effect, which consists of the emission of electrons (electric current) that are produced when light hits certain surfaces.
In the case of PV solar energy, these surfaces are cells formed by one or more panels of semiconducting materials, in most cases silicon, and are covered by a transparent glass that allows solar radiation to pass through and minimizes loss.
Cells are grouped into modules (panels) for integration into PV systems. Solar modules have an estimated life of 25 years and their performance after 20 years is above 80%. Regardless of this, there is ongoing research to increase their efficiency.
PV modules generate DC power that is transformed into AC power through the use of an electrical device called an “inverter”.
Subsequently, and as necessary, the electrical energy that is produced goes through a “transformation center” that adapts the electricity to the power and tension conditions of the transportation line for consumption.
In addition, there is usually the incorporation of a monitoring and data management system that enables tracking of the energy produced by the PV solar system.
The following are some of the essential components of every PV solar system:
The inverter is an electrical device that converts the current that is continually generated by the solar panels into AC power.
This equipment is normally located in an accessible place, as close as possible to the modules. The fact that the inverters produce a slight noise must be taken into consideration when deciding where the equipment will be placed.
The support structure is the mechanical structure used to mount the solar panels on the roof, walls or ground.
There is a great variety of structures, which should be carefully evaluated depending on the place where the PV system will be installed.
In Colombia, every client that has self-generation systems, as is the case of PV solar systems, must have a Bi-Directional Meter.
A Bi-Directional Meter can measure the flow of electrical energy in two directions. It can measure how much energy a client receives from the utility company, and at the same time, it differentiates between the production of energy from the solar system and the client’s consumption of energy from the grid.
How much energy do Solar Panels produce?
All solar panels are classified as having Direct Current (DC) power produced under standard test conditions. For example, if 100 panels are installed and each one has a power of 250 watts (W), the system can have an approximate output of 25 kilowatts (kW). Having said that, the daily or monthly energy that this system can produce is directly related to the amount of solar radiation of the place where the system is installed.
Types of systems
A common way to classify PV systems is according to their scale, in which solutions range from residential to large-scale or “solar utility.” ISC focuses on the following solutions: