Development and Test of Solutions to Enlarge the Power of PV Irrigation and Application to a 140 kW PV-Diesel Representative Case

Abstract

The current state of the art of photovoltaic (PV) irrigation systems is limited to PV peak powers below 40 kWp, which does not cover the irrigation needs of farmers, co-operatives, irrigator communities, and agro-industries. This limitation of power is due to two main technical barriers: The quick intermittence of PV power due to the passing of clouds, and the maladjustment between PV production and water needs. This paper presents new solutions that have been developed to overcome these barriers and their application to the design and performance of a 140 kWp hybrid PV-diesel system for the drip irrigation of 195 ha of olive trees in Alter do Chão, Portugal. The performance of the solutions was analysed during two years of real operation. As the performance of the PV system is not only affected by intrinsic-to-design characteristics, but also by circumstances external to the system, new performance indices were developed. As an example, the percentage of use of PV electricity, PVSH, was 78% and 82% in 2017 and 2018, respectively, and the performance ratio of the PV part, PRPV, was 0.79 and 0.80. The economic feasibility was also analysed based on experimental data, resulting in savings in the levelized cost of electricity of 61%.

Multivariate Analysis of a Wind–PV-Based Water Pumping Hybrid System for Irrigation Purposes

“…Another approach for the improvement of the supply system's reliability is the use of diesel generators. This solution is in conflict with the green energy concept, but according to [46], the solution with a diesel generator has advantages over batteries due to the security of supply and the lower cost. This allows the operation of high power systems, i.e., 140 kWp instead of 40 kWp.…”

“…Despite the statement in [46] against the application of batteries in the supply systems for irrigation purposes, this solution is widespread in the literature. This is the reason for the estimation of the battery storage's influence on the studied configurations.…”

Operational scheduling of responsive prosumer farms for day‐ahead peak shaving by agricultural demand response aggregators

“…16 Afterward, an energy management framework was suggested to supply the irrigation systems by the joint solar and diesel power generators. 17 Besides, a research study investigated the practicality of using solar power-based irrigation systems for the agricultural sector. 18 In 2019, a prominent research study suggested the deregulation in the agricultural industry to facilitate the integration of renewable energies to electricity markets.…”

“…First of all, in 2018, a research study presented a novel coordination approach to optimize the operation of the pumped‐storage unit, water irrigation system, and intermittent wind turbines in an agricultural microgrid 16 . Afterward, an energy management framework was suggested to supply the irrigation systems by the joint solar and diesel power generators 17 . Besides, a research study investigated the practicality of using solar power‐based irrigation systems for the agricultural sector 18 …”

Design, implementation and evaluation of a control system to optimize the performance of a Permanent Magnet Synchronous Motor (PMSM) supplied by a stand-alone Photovoltaic System without batteries

“…By its own nature, PV energy generation is discontinuous and highly dependent on the time of the day and weather conditions. This fact makes that off-grid applications, where it is required a constant energy supply, need the design of a hybrid system with a non-renewable energy source [8] or the use of a system that allows to store the exceeding energy produced on higher irradiance hours in order to use it when generated energy is insufficient or null. Energy storage systems present problems of price, viability and maintenance necessities [9]- [10], and they are the main obstacle to the growth of installed power in photovoltaic systems outside the grid.…”