PV Watts
The NREL provides a PV Watts calculator tool which estimates the energy production and cost of energy of grid-connected photovoltaic (PV) energy systems throughout the world. It allows homeowners, small building owners, installers and manufacturers to easily develop estimates of the performance of potential PV installations. Users can compare the energy produced by different PV systems based on location, orientation, shading type, system size, panel type, or a combination of these factors.
PV Power
PV Power is an online tool for calculating electricity production from photovoltaic (PV) solar panels for any location worldwide and any date within the years 1950-2050. The calculations are based on official reports from the World Meteorological Organization (WMO), solar irradiance data from NASA's Langley Research Center Atmospheric Science Data Center (ASDC), input data provided by users or automatically generated through satellite images obtained via Google Maps API web services and hourly weather forecasts provided by Open Weather Map web service licensed under CC BY-SA 4.0 license.
http://www.solarpowercalculatorapp.com
Solar Site Assessment Tool (SSAT)
SSAT is a free, web-based tool that uses machine learning to estimate the solar potential of a given site. These sites are evaluated on a scale of 0 (poor suitability) to 100 (excellent suitability). The system is trained using aerial imagery and GIS datasets, which allows the tool to make predictions about what types of roofs would be suitable for rooftop PV. It does not provide detailed information about shading or other physical characteristics beyond roof type, but it can help identify areas that should be easily evaluated as having good solar potential rather than poor potential.
SPOT6/7
The SPOT 6/7 satellites are advanced imaging satellites capable of capturing high-resolution satellite imagery, making them ideal for solar mapping. The SPOT 6/7 data can be used to analyze potential sites for utility-scale solar installations and help you better understand the terrain. If it's a residential or commercial project, satellite images can help home or business owners determine if their roof is suitable for solar panels or where the best location would be on a property.
https://earth.esa.int/web/eoportal/satellite-missions/s/spot-6-7
Nearmap
Nearmap is an Australian company that provides high-resolution aerial imagery, oblique 45° imagery, and vertical views to help you assess solar potential for your site. Nearmap’s continues to collect oblique 45° imagery for more than 80% of the US population and almost 100% of the Australian urban population annually. The Nearmap capture schedule offers historical aerial imagery collection over the past few years so you can track progress on development locations and perform historical analysis.
Eagleview
Eagleview is a mapping company that provides high-resolution aerial imagery and 3D models to its customers. Eagleview uses a combination of satellite and aircraft imagery. The company's Pictometry software provides image capture, management, and analysis technologies that allow users to create their own maps. The software can be used on both desktop computers and mobile devices.
Google Earth Pro
Google Earth Pro is another option for accessing satellite imagery. Google Earth Pro provides the same functionality as Google Earth, but it is a bit more sophisticated. It can be used to create custom maps and import GIS data. In addition, it allows you to calculate the area of any given shape and measure distance between points.
However, this version of Google Earth requires users to download an application instead of using a web browser. If you have access to a Windows computer or virtual machine and are comfortable with this process, give it a try!
https://www.google.com/earth/versions/
Use these companies for mapping solar resources
You’re interested in mapping solar resources, but don’t know where to start? There are plenty of companies out there who can help you with this. Here are some of the most popular ones.
Here is a map of Solar Related Companies in U.S.