The paper considers effectiveness of a penetration of renewables into potential Northeast Asia power system interconnection. Renewables are currently in the mainstream of expansion of energy sector in the world and in Northeast Asia, particularly. Formation of NEA power interconnection will increase utilization of variable and poorly predictable renewable generation. Economic incentive for penetration of renewables, like CO2 emission tax, is studied. The study revealed that quite significant tax is needed to be imposed to induce non-fossil fuel generation capacities, including renewable ones, to be added to power systems.