Image: Tofan Singh Chouhan – Shutterstock.
Among the various applications for photovoltaic panels is their use in the generation of solar energy for agricultural irrigation.
As in domestic and commercial installations, here the technology is also presented as an economical and sustainable solution to replace other sources of energy.
Using only sunlight as “fuel”, the plates can supply all the electricity needed to power irrigation systems, regardless of type or size.
It is not surprising that the number of photovoltaic systems installed in rural areas is growing day by day worldwide.
Today we talk about how solar technology works and what types of systems exist for irrigation systems. You will also learn what equipment is needed in each of them.
Photovoltaic energy for irrigation: How does it work?
A solar energy system for irrigation works using photovoltaic panels.
As we already know, a solar panel uses only sunlight to generate electrical energy.
This transformation of light into energy takes place inside each of the photovoltaic cells that make up the plate.
Each model of solar panel has a certain generating power that, by itself, is not enough to power an irrigation system.
Therefore, it is necessary to calculate the number of panels that will be needed based on the consumption of each irrigation project.
When they are together and connected, they form what we call a photovoltaic kit.
Solar energy system for irrigation: Types
Therefore, if the plates work from sunlight, their generation will depend on the amount of sunlight available.
On cloudy days, the panel generation will be less, while at night it is zero.
There are two main types of solar power systems for use in the field that differ in the way they deal with this intermittency.
Systems connected to the network.
Systems that work connected to the distributor’s electrical network.
In this way, when the panel’s generation is lower, the rest of the necessary energy is extracted from the electrical network.
When the generation of the panels is higher than the energy consumed at that moment, the surplus is sent to the electrical network.
Depending on the country where you reside, that electricity you pour into the grid will be converted into money or a discount on your electricity bill.
In rural areas located in places with access to the electricity grid, this is the most recommended type of installation.
Image: GoneWithTheWind – Shutterstock.
As the name suggests, these are systems that are NOT connected to the electrical grid.
There are three subtypes of isolated systems:
- With storage : in these systems, a battery bank is sized so that the energy from the plates can be stored. In this way, on cloudy days or at night, the stored solar energy can be used to power our irrigation system.
- No storage: as we do not have batteries, the system will only work while there is sunlight. Therefore, this type of installation is not recommended if we have the constant need for irrigation.
- Hybrid systems: these are the systems that use solar panels together with another electrical generation system. It can be a wind turbine, a biomass system or even the traditional diesel generator. A hybrid system may or may not have an energy storage system.
Solar kit for irrigation.
A solar system for irrigation does not only use photovoltaic panels.
Other equipment is needed to use the electrical energy generated by the panels.
A photovoltaic system must have:
- Photovoltaic solar panel : set of plates that capture sunlight, converting it into electricity through its photovoltaic cells. The solar panels for sale on the market are made up of 60 or 72 cells each.
- Photovoltaic inverter : it is considered the “brain” of a photovoltaic system. The inverter is in charge of adapting the energy generated by the plates to the standard that we use in our electrical network and equipment. Technically: from direct current to alternating current. It also controls the flow of energy, pulling or injecting energy into the grid (On-Grid systems) or into the battery bank (Off-Grid systems).
- Junction box: it is the set of components for the protection of the modules against the surges of the network and other electrical damages in the systems of the network.
- Support and mounting structures : metal structures in which the solar panels are fixed. When installing panels on roofs, the rail system is used. For the installation of the panels on the ground, solar plant type structures are used. In addition to providing the necessary support and fixation, the structures guarantee the correct inclination of the plates in relation to the sun, maximizing their electricity generation.
- Cabling: the entire set of cables and connectors to make the electrical connection between the different components of the rural solar kit.
- Battery bank: the system of batteries necessary to store energy in isolated systems. The number of batteries must be very well calculated so that the stored solar energy can supply the irrigation system in times of little or no sunlight.
- Charge controller: it is the equipment that efficiently manages the charge of the batteries, feeding them correctly.
When we talk about solar irrigation systems, the main advantage that we must mention is cost reduction.
In the case of projects in isolated areas of the commercial electrical grid, photovoltaic kits are shown as a much cheaper option than diesel generators.
The useful life of a solar panel is 25 years, years in which it generates free energy through sunlight, while diesel generators always need fuel.
Solar energy is also a better option than using the electricity grid.
In addition to the high price of energy, its constant inflation makes it more expensive to consume the same amount of energy each year.
With the photovoltaic system you are free from these price and tax increases, because it guarantees your energy through sunlight, free and available in great abundance throughout the world.
It must also be remembered that the system can be designed to feed other activities in the field, further increasing the savings that we can obtain.
Another advantage is that the electricity we generate and consume is 100% clean.
Unlike diesel generators, solar panels do not emit polluting gases (CO2) or any other type of pollutant into the environment.
Therefore, investing in a solar-powered irrigation system is solving two problems at the same time: reducing electricity costs and contributing to a more sustainable environment.
How much does a solar energy project for irrigation cost?
The photovoltaic project must be designed exclusively for each case.
Therefore, to know the cost of the ideal system for your case, you should request a quote from a company specialized in solar energy. It is recommended that you contact two different companies to be able to compare the budgets and decide on the one that best suits your needs.