solar matter is a renewable / inexhaustible discoveries
renewable_resource is tangible_thing. renewable_resource is natural_resource. renewable_resource is not natural_resource. solar_energy is not alternative_energy. solar_power is not clean_renewable_energy_source. natural_gas is renewable_resource. solar_power is clean_renewable_energy_source. solar_energy is alternative_energy. natural_gas is not renewable_resource. renewable_resource is not tangible_thing.