- This year the objective of implementing the wide variety of installation models offered by the market has been fulfilled, both in isolated and in grid connection.
- Photovoltaic plants are running on raft and ground.
At the beginning of 2017, the irrigation sector had already been making photovoltaic installations for direct supply of private pumps, mostly isolated, to replace or complement the use of generator sets for several years. At that time, Power Electronics SD700SP drive was already the most installed. With the implementation of this solar pumping system it was possible to reduce operating costs and increase energy efficiency.
The implementation of subsidies by public administrations for self-consumption and the generation of renewable energies has led to the realization of multiple projects, developed by the same engineering that at the time participated in the irrigation modernization process.
Once all of these projects have been presented, and considering the favorable resolutions or not of the different administrations, the works are in the execution phase, and most of them are operational since May.
With the implementation of these new projects, the objective of implementing the wide array of installation models offered by the market is met, both in isolated (when solar panels are the only source of energy), and in network connection.
Installations in isolated operation (with hybrid operating capacity):
These types of installations allow the agricultural development works independent of the general electricity grid, and may become self-sufficient with energy consumption. The photovoltaic panels, on raft and on the ground, generate enough electrical energy to supply the different motors and electrical elements of the irrigation network. Likewise, these systems can also be applied in isolated areas with poor access to the electricity grid.
The SD700SP drive is connected to the photovoltaic field generating the minimum power to start and accelerate the pump. A system simulation allows you to determine the minimum frequency that ensures the minimum operating flow. In addition, the drive automatically searches for the maximum power point, therefore, the solar field always delivers the maximum available energy, regardless of whether it is summer or winter, or the intensity of radiation.
These types of facilities are increasingly used by the Spanish communities of irrigators who are looking for a constant and efficient irrigation system, and reduce electricity costs. This is the case of the communities of Lliria and Villena (Valencia Region), Tobarra (Albacete), Mérida, and in Huesca, the communities of Pedrola, Almunia and Veintiseis Bis in Sangarrén, among others, that have opted for isolated systems with possibility of network connection.
Installations in hybrid operation:
In this type of installation, the SD700SP drive is connected to the photovoltaic (DC) field but also allows simultaneous connection to the grid (AC) generating the minimum power to start and accelerate the pump. During the day, the energy generated by the solar panels is injected into the motor, and when the solar radiation is reduced or lowered, the inverter absorbs more current from the grid instantaneously in order to maintain a constant power balance.
There are many irrigation communities in Spain that already use this hybrid power generation system, such as the Huerto Chico in Lorca and Miraflores in Jumilla (Murcia), Acequia de Sora de Zaragoza, and others that will soon operate in isolation such as that of Barranco de Zorreras in Jaén, or that of Valdecañas in Cáceres.
Self-consumption facilities with connection to own Medium Voltage grid and sale of excess energy:
On the other hand, many irrigations communities are beginning to implement self-consumption facilities with connection to their own medium-voltage grid through solar inverters. This system allows the generation of energy for use and maintenance of the farm, both directed to the irrigation system and to the rest of productive activities. In addition, it allows to revert to the grid, the remaining energy and lower the electricity bill.
This is the case of the irrigation community of the Valle Inferior(Andalusia), which has installed two HEMK inverters with the MV SKID 3 MW turnkey solution. At present it is generating in self-consumption and is processing the legalization to be able to sell the remaining energy. Also, in Extremadura, the Guadiana irrigation community has installed a 2.4 MW HEMK Inverter and has already executed the first phase of the photovoltaic field.
It is certainly a new market, which is forcing administrations and power companies to mark legalization procedures that to date did not exist, changes that result in a notable improvement in the sustainability of farms, reducing their water and environmental footprint, and aligning with the new objectives of community agricultural policy.