A simple method estimates and economic indicators of photovoltaic systems for drip irrigation

Abstract

Renewable, environment friendly, photovoltaic (PV) solar energy have been one of the most attractive means for pumping the water needed to irrigate crops. However, since at the present time PV systems still suffer from high investment costs it is necessary to accurately dimension the installations. This study presents a simple but accurate a process to estimate the required dimension of a photovoltaic installation designed to power a pumping system for the drip irrigation of a raspberry plantation in W Serbia. The methodology is based on systematic approach to the problem, taking into account all relevant elements, from PV pumping system, local climate, soil properties, depth of well, characteristics of the crop, to irrigation system. With an array of579 Wp it was found that the system is able to irrigate, without deficit of water, 1.0 ha raspberry plantation. The methodology presented here is applicable for a range of crop areas, and a variety of crop types in regions of similar climate, soil and latitude. Besides the advantages for the environment, since it uses a renewable energy, a study on the economic viability of a photovoltaic system shows that it is similar to conventional systems which use a generator unit. Moreover, the high price of fossil fuels guarantees a progressive advantage of photovoltaic systems.

Obnovljiva, ekološka, fotonaponska (FN) solarna energija je jedan Od najatraktivnijih načina za pumpanje vode potrebne za navodnjavanje useva. Međutim, pošto su u ovom trenutku FN sistemi još uvek iziskuju visoka investicionim ulaganjima, neophodna je precizna procena veličine odgovarajuće instalacije. U ovom radu je predstavljen jednostavan, ali precizan metod za procenu potrebne fotonaponske instalacije za pumpanje sistema za navodnjavanje kap po kap na porodičnoj plantaži maline u zapadnom delu Srbije. Metodologija se zasniva na sistematskom pristupu problemu, uzimajući u obzir sve relevantne elemente FN pumpnog sistema, lokalnih klimatskih osobina zemljišta, karakteristike useva, kao i potrebe za sistemom za navodnjavanje. Uz niz od 579 Wp utvrđeno je da je ovakav sistem sposoban za navodnjavanje, bez deficita vode, za 1 hektar maline. Ovaj način je primenljiv i za druge useve u regionima slične klime, zemljišta i geografske širine. Pored prednosti za životnu sredinu, jer koristi obnovljivu energiju, analiza o ekonomskoj opravdanosti pokazuje da je fotonaponski sistem sličan konvencionalnim sistemima koji koriste druge generatore. Štaviše, visoka cena fosilnih goriva garantuje progresivnu prednost fotonaponskih sistema.