Several web-tools, available from the Photovoltaic Geographical Information System (PVGIS) online service, are freely available for use in viticulture.
The Photovoltaic Geographical Information System (PVGIS ©European Communities, 2001 – 2017) was developed from solar radiation data estimated from satellite using the Satellite Application Facility on Climate Monitoring (CM SAF) models and representing the period 1996 – 2011. In areas North of 58° N the data are derived from ground station measurements collected within the European Solar Radiation Atlas and interpolated spatially. The figures show examples of estimations for two locations, i e San Michele all’Adige, North Italy, and Stellenbosch, South Africa.
The PVGIS service allows to simulate the photovoltaic potential of a PV system, according to the site location and horizon mask, the PV technology, installed peak power, yield and energy losses, as well as mounting options like slope (0 = horizontal; 90 = vertical) and azimuth (-90 = oriented to the East; 0 = to the South; 90 to the West; + or -180 to the North) to optimise light harvesting.
Several web-tools, available from the PVGIS online service, can be used in viticulture. In particular, the “Show horizon” option allows the calculation of both the astronomic and topographic sunrise, sunset and maximum potential day length, on a sunny day with no cloud cover. Moreover, the “Daily radiation” tool offers the possibility to calculate the monthly irradiance on the PV surface. The PVGIS service simulates the monthly irradiance on the canopy surface using “slope = 90 (vertical)’’ and the row orientation angle as azimuth value. It therefore offers the possibility to simulate the monthly harvesting of sunlight by the canopy.
Finally, the “PV estimation” service provides the estimation of the optimum inclination and orientation of the PV module (i e canopy) as affected by the horizon mask, to maximise the annual light interception.
PVGIS services and queries can also be embedded into new tools (both local and online) to support the site/terroir selection and a proper vineyard design (row orientation, row and vine spacing, trellis system, etc), as well as optimum foliage management to maximise light harvesting in the vineyard during the entire growth season.
Several web-tools, available from the PVGIS online service, can be used in viticulture. The “Show horizon” option allows calculation of both the astronomic and topographic sunrise, sunset and day length. Monthly irradiance on the canopy surface can be calculated, thus monthly sunlight harvesting simulated by using the “Daily radiation” tool. PVGIS services and queries can also be embedded into new tools to support terroir selection, vineyard design and optimum foliage management to maximise seasonal light harvesting in the vineyard.
We would like to thank the Agricultural Research Council and South African wine industry (through Winetech) for funding. Details of this popular script can be found in the following scientific articles (and the references therein):
Hunter, J.J., Volschenk, C.G. & Zorer, R., 2016. Vineyard row orientation of Vitis vinifera L. cv. Shiraz/101-14 Mgt: Climatic profiles and vine physiological status. Agricultural and Forest Meteorology 228, 104 – 119.
Zorer, R., Volschenk, C.G. & Hunter, J.J., 2017. Integrating Geographic Information Systems and hemispherical photography in the assessment of canopy light profiles in a vineyard. Agricultural and Forest Meteorology 232, 672 – 681.
– For more information, contact Roberto Zorer at firstname.lastname@example.org or Kobus Hunter at email@example.com.