Power utilities in the world are required to ensure that electrical energy demands from the customer aremet in accordance with the policy of the country. They are also to ensure that the electrical power is generated within minimal cost when serving the load demands of the country. Thus, the total load demand must be approximately shared among the generating units with an objective to minimize the total generation cost for the system in order to satisfy the economic operation of the system. Economic load dispatch is a procedure to determine the electrical power to be generated by the committed generating units in a power system so that the total generation cost of the system is minimized, while satisfying the load demand, equality and inequality constraints simultaneously. This paper presents the economic load dispatch problem solved using Ant Colony Search Algorithm(ACSA) technique. ACSA is a meta-heuristic algorithm for solving hard combinatorial optimization problems. In this paper, the proposed algorithm was written in MATLAB code and was tested using Egbin Thermal Power Station in Nigeria as our case study with six generating units. The result obtained using ACSA was compared with the Lambda method. The results revealed that the proposed algorithm has the merit in achieving optimal solution for addressing the operating cost and power loss problems.