The feasibility of heating sector integration into future highly renewable electrical grid is examined for a regional and pan-European network. A novel geographical weather dependent model for calculating the heat demand using a temporal resolution of an hour with a spatial resolution of 40 x 40 km(2) and an optimized solution for the utilization of excess renewable generation with least energy needs is presented. Heating sector is modeled and coupled separately with two different heat coupling models, heat pump coupling and electric-resistance coupling, both having heat-storage and gas-boiler. Results show coupling with the regional network requires least heat-storage capacity and coupling with an individual country network requires the least gas-boiler capacity. However, coupling with the pan-European network results in least balancing energy needs. It is found that heat-pump coupling provides more benefit than the electric-resistance coupling, with 4 times more heat-storage energy and 38% less requirement for the gas-boiler energy. Optimum energy mix between the heat-storage energy and gas boiler energy suggests that the present amount of excess generation is not enough to fully support the heating sector, but if the renewable energy generation is increased by 50% then heat-storage will play an important role. (C) 2017 Elsevier Ltd. All rights reserved.