New software calculates a city's potential
Climate data are taken into account
Researchers at the University of Göteborg in Sweden have come up with a new computer program to analyze the potential of solar power generation and solar heat for entire cities. The program supports a wide range of data formats.
Called Solar Energy from Existing Structures (SEES), the new software collects, stores, analyzes, and graphically displays geographical data for roofs to determine their suitability for solar arrays. It calculates both the angle of solar incidence and shading from trees and nearby structures. In addition to this data, the roof angle and climate data are included with a resolution of up to an hour. The program shows building roofs in their actual environment. In the model, the sun shines on the building's three-dimensional surroundings to correctly reveal shading, which can also be calculated for individual months and the year as a whole. You can therefore select the individual roof segments especially suitable for the installation of a solar array. The program also shows the kilowatt-hours of insolation per square meter during a certain time frame.
None of this is possible, however, without the right data input. Above all, the simulation of shading and roof angle requires laser measurements via helicopter, which already exist for a number of cities. While they are generally used for other purposes (such as three-dimensional simulations), the SES smoothly supports such data. The tool can also be used to calculate individual projects or planned buildings because it can also process normal CAD data used in the planning of buildings.
As a reference project, the researchers started with their hometown of Göteborg, where they covered some 140,000 buildings. "If we put photovoltaic cells only on the best roofs, we could already cover 20 percent of the city's current power demand," concludes Per Jonsson of consulter WSP, a project partner.
The researchers believe that their project is mainly beneficial in terms of awareness-raising, not financially. "If we can show people the energy potential of their own roofs, they will be more likely to want to tap that potential," Jonsson says. In doing so, the researchers hope not only to raise the awareness of owners of single-family homes, but mainly the awareness of politicians, urban planners, and owners of large buildings. (Sven Ullrich / Craig Morris)
