The weather files we normally use are based on historical records often spanning a few decades. Are there any resources which provide projected weather files for future years (ideally projected changes in irradiation and temperature because of changes in the climate - even some rough estimates would be sufficient here). Many thanks!
For now, the NREL National Solar Radiation Database (NSRDB) has historical data. There are plans to add forecast data, but I'm not sure when that data might be available.
We have listed some other sources of weather data on the Weather Data page. Some of these may provide forecast data: sam.nrel.gov/weather-data.html