NOVELTY - A system (100) for providing energy (1'',1''') for an energy grid (300) based on energy (1) provided by renewable energy source (10) comprises hydrogen-nitrogen (H2-N2)-production unit (20) for producing hydrogen (4) and nitrogen (5); mixing unit (30) for forming H2-N2-mixture (8); NH3 source (40) for generating gas mixture (9) containing ammonia (NH3), where NH3 source has NH3 storage vessel (44); NH3 power generator (200) which has combustion chamber (201); and heat distribution system (91-94) with heat exchangers (92-94) in thermal contact with and assigned to 1st components.    USE - A system for providing energy for energy grid based on energy provided by a renewable energy source (claimed).    ADVANTAGE - Unused process heat, e.g. waste heat, is collected from 1st suitable stages of the system and directed to 2nd suitable stages of the system to improve the efficiency of the 2nd stages, improving the overall efficiency of the system. The presence of ammonia storage vessel as a buffer allows a better flexibility of providing energy to the energy grid, and as a result, an improved load balancing.    DETAILED DESCRIPTION - A system for providing energy comprises hydrogen-nitrogen H2-N2-production unit, which is operated by using energy provided by renewable energy source, for producing hydrogen and nitrogen; mixing unit for receiving and mixing hydrogen and nitrogen produced by H2-N2-production unit to form H2-N2-mixture; NH3 source for receiving and processing H2-N2-mixture to generate gas mixture containing ammonia (NH3), where NH3 source has NH3 storage vessel for storing at least a part of NH3 of gas mixture containing NH3; NH3 power generator for generating energy for energy grid, where NH3 power generator is fluidly connected to NH3 storage vessel to receive gas stream containing NH3 from NH3 storage vessel, and NH3 power generator has combustion chamber to combust received NH3 of gas stream to generate energy for energy grid; and heat distribution system with heat exchangers, where each one of the heat exchangers is in thermal contact with and assigned to 1st components (21, 41, 200) of the system for receiving process heat from the assigned 1st component during operation of the 1st component, and each one of the heat exchangers is arranged and configured to transfer at least a portion of received process heat to 2nd components (32, 45, 52) of the system. An INDEPENDENT CLAIM is included for method for providing energy for an energy grid based on energy provided by a renewable energy source which involves using at least a part (1') of the energy from renewable energy source to produce H2 and N2 in a H2-N2-production unit, mixing H2 and N2 in a mixing unit to form H2-N2-mixture, processing H2-N2-mixture in an NH3 source to generate gas mixture containing NH3, storing NH3 of gas mixture containing NH3 in an NH3 storage vessel, directing NH3 stream from NH3 storage vessel to combustion chamber of an NH3 power generator for combusting NH3 of NH3 stream to generate energy for the energy grid, where at least a portion of process heat generated in 1st components of the system during operation of the 1st component is transferred to 2nd components of the system.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic diagram of the system for load balancing of intermittent renewable energy source.    Energy provided by renewable energy source (1)    Part of energy provided by renewable energy source (1')    Energy for energy grid (1'',1''')    Hydrogen (4)    Nitrogen (5)    Hydrogen-nitrogen mixture (8)    Gas mixture (9)    Renewable energy source (10)    Hydrogen-nitrogen production unit (20)    1st components (21, 41, 200)    Mixing unit (30)    2nd components (32, 45, 52)    Ammonia source (40)    Heat distribution system (91-94)    System for providing energy (100)    Ammonia power generator (200)    Combustion generator (201)    Power grid (300)