he module allows electricity generation without excessive shade for the crop.
Crops chosen for the first testing are tomato and pepper, due to both of them are world widely spread, with high light needs and they have high added value in greenhouse farming.
ULMA, one of TEKNOLUR main suppliers, and Tecnalia have built an photovoltaic facility on one of the two crystals greenhouse plants of about 400 m2. The new module allows electricity generation without excessive shade for the crop.
Taking advantage of the annual oscillation on the solar elevation through an optical system based on lenses, solar radiation derivation according to the season is achieved. Without need of any mechanic solar monitoring system, technology allows to satisfy any crop needs.
During winter (from October to February), light inside the greenhouse, key for the plant growing, hardly decreases.
During summer, on the other hand, the optical system redirects sunlight towards the photovoltaic module cell, achieving a double objective: cooling the greenhouse in very high temperature period, and increase electric production through a photovoltaic system.
Summer and winter test
It is being tested in a ULMA greenhouse located in Neiker technology center in Derio (Spain). Selected crops for the first testing are tomato and pepper. They have been chosen because are two of the most world widespread with high light needs and they have high added value in greenhouse farming.
Testing during summer, the most crop critical parameters have been measured, such as PAR and total radiation, humidity and temperature. Furthermore photovoltaic panel growing crop quantity and quality have been compared with normal crystal cover growing crop, getting very good results, and since medium November, until the end of March 2012 winter testing will be made, monitoring the same parameters and hoping to have similar results.
Regarding electricity production, first measurements point to a 15% annual improvement comparing with a standard photovoltaic system.
New photovoltaic system advantage
Therefore, the new module allows photovoltaic and growing devices to live together. It acts as a seasonal greenhouse radiation and temperature control system, in addition of being a possible support for the farmer´s economic activity, through the selling and/or self consumption of the energy obtained.
Developed technology avoids the problems connected with excessive winter shade and summer sunlight, in a simple, robust and effective way. Previously validated on field in ULMA agrícola greenhouses, the consortium pretends to have the product ready to commercialize on second semester 2012.