Solar energy: googling your roof

(Nanowerk News) Internet users can assess the solar potential of their roofs through a platform developed by Google. The online “calculator”, which was only accessible in the US, has now reached Europe, starting in Germany
Despite increasing talk about renewable energy, many people remain far removed from what’s going on. To tackle this, various projects have been developed over the years helping users to better understand and use green energy sources.
bird's bview of house roofs
Among these experiences is Google’s Sunroof platform that, with a few clicks, enables homeowners to calculate the solar potential of their roofs and the cost-benefit ratio of installing solar panels.

People can find out in a matter of seconds if their roof is an untapped economic and environmental resource. And internet giant Google has of course anticipated that internet users may want to “share” their discovery, which could trigger a viral word-of-mouth on social media and thus raise greater awareness about renewable energy.

Since its inception in 2015, the platform had only been available in the US where it covers some 60 million buildings. But it has now reached Europe. Thanks to an agreement between Google and E.ON, a European energy company based in Düsseldorf, Germany, Sunroof has started to provide information on 7 million German buildings (where some 40% of the population lives) in the urban areas of Munich, Berlin, Frankfurt Rhine- Main and the Ruhr.
The platform exploits 3D technologies such as Google Earth, based on satellite imagery, and the web mapping service Maps. “All users need to do is enter their address online,” says Markus Nitschke from the E.ON Group, “The solar potential of the roof throughout the year is calculated according to weather data, the sun’s position across the seasons, and the surface and slope of the roof. Also any shadows projected by surrounding buildings or trees can be taken into account.”
The obtained data are used to estimate energy production, the investment required to install a photovoltaic system (taking incentives into account) and the savings on electricity bills. The platform can also advise on the characteristics that the system should have (how many panels needed considering the roof surface etc.) and can provide a list of nearby developers that users can contact to get more information.
Besides Google, other companies have tried to develop similar but smaller scale projects. For example the Italian Enerpoint offers free software for calculating the best system for a building. However, to use it you need to know and enter specific parameters such as roof orientation surface characteristics. “We launched a set of four photovoltaic simulators in 2011 generating thousands of requests for residential, agricultural, industrial and ‘stand alone systems’, not connected to the electricity grid,” says Valentina Leva, the company’s marketing manager.
David Martin from the R&D department of the Spanish company Onyxsolar hopes that a system like Google’s platform will be also available in his country, and elsewhere in Europe. It is a way to make citizens aware of the need to reduce domestic consumption and to discover the hidden, renewable energy potential of the buildings they live in.
“It would be a step forward and give momentum to the solar energy market,” he points out. The Spanish developer of PV solutions is cooperating with the European project R2Cities, whose aim is to study “smart” replicable solutions for renovation of buildings at district level, in order to dramatically cut energy consumption in cities. Its technologies are being tested in Valladolid (Spain), Genoa (Italy) and Kartal near Istanbul (Turkey).
Source: By Elena Veronelli, R2Cities