Method for estimating energy generated by a solar system installation in a predetermined geographic area, the method comprising, at each predetermined time instant: - retrieving measured values of at least one weather parameter and of solar irradiance in respect of said predetermined geographic area, said measured values being related to a first time slot before said predetermined time instant; - performing an auto-regression analysis of the measured values; - estimating, based on said auto-regression analysis, a relationship between the at least one weather parameter and the solar irradiance; - retrieving forecasted values of said at least one weather parameter in respect of said predetermined geographic area, said forecasted values being forecasted for a second time slot after said predetermined time instant; - performing a regression analysis of said relationship between the at least one weather parameter and the solar irradiance and of said forecasted values; - forecasting a solar irradiance in said second time slot based on said regression analysis, and - estimating energy generated by the solar system installation in said second time slot according to the forecasted solar irradiance and at least one solar system parameter, wherein: said performing an auto-regression analysis and said estimating a relationship comprise providing the measured values of at least one weather parameter and of solar irradiance to an encoder network of a sequence-to-sequence neural network, thereby obtaining encoded measured values indicative of said relationship between the at least one weather parameter and the solar irradiance, and wherein said forecasting comprises providing said encoded measured values and said forecasted values to a decoder network of the sequence-to-sequence neural network. - retrieving measured values of at least one weather parameter and of solar irradiance in respect of said predetermined geographic area, said measured values being related to a first time slot before said predetermined time instant; - performing an auto-regression analysis of the measured values; - estimating, based on said auto-regression analysis, a relationship between the at least one weather parameter and the solar irradiance; - retrieving forecasted values of said at least one weather parameter in respect of said predetermined geographic area, said forecasted values being forecasted for a second time slot after said predetermined time instant; - performing a regression analysis of said relationship between the at least one weather parameter and the solar irradiance and of said forecasted values; - forecasting a solar irradiance in said second time slot based on said regression analysis, and - estimating energy generated by the solar system installation in said second time slot according to the forecasted solar irradiance and at least one solar system parameter, said performing an auto-regression analysis and said estimating a relationship comprise providing the measured values of at least one weather parameter and of solar irradiance to an encoder network of a sequence-to-sequence neural network, thereby obtaining encoded measured values indicative of said relationship between the at least one weather parameter and the solar irradiance, and wherein said forecasting comprises providing said encoded measured values and said forecasted values to a decoder network of the sequence-to-sequence neural network.