Purpose-The purpose of this study was to determine the efficacy value of national street lighting on energy conservation and carbon dioxide (CO 2) emission reduction. Design/Methodology/Approach-The methods used are the measurement of electrical parameters (low voltage network), the national road illumination level with SON lamp specification, 400 W, 180 W, and 110 Lumen/W, the simulation of energy conservation calculation, and the CO 2 emission reduction obtained by utilizing panel solar cells as a source of energy and LED lights for illumination. Finding-The results show the efficacy of a 100-W light bulb at an altitude of 8 m for the following specification of light bulbs: LED, 130 Lumens/W, SON, 110 Lumen/W, and MBF, 53 Lumen/W gives the illumination level respectively 13,913 Lux, 11,773 Lux, and 5,672 Lux. By replacing the 180 W SON lamp with an LED, 100 W, of energy conservation by 3.171 GW h is obtained, which is equivalent to a CO 2 emission reduction of 3.641 kTon CO 2 .

Electric power Energy conservation Carbon emisson Light lamp efficacy.Utilization of conventional electrical energy as the fulfillment of living necessities for lighting and electrical equipment is increasing, which can cause problems in the provision of electrical energy. Energy management is needed to solve the problem of energy utilization, especially the problem of energy demand during peak load. The greatest energy consumption during peak loads is for building lighting at night, including street lighting. The use of electrical energy for the national public road lighting is getting bigger due to the increase in the length of national roads each year significantly. In North Sumatera Province, by the end of 2019 the total length of the national road segment is 2632.22 Km, an increase of 328.56 km from the previous road length. By increasing the power factor of the existing national street lighting and utilizing lamps with high efficacy and utilization of solar cells on the increase of national roads will be obtained energy conservation and the need for electrical power for the purposes of street lighting by increasing the road segment becomes fulfilled.Copy Right, IJAR, 2018,. All rights reserved. …………………………………………………………………………………………………….... Introduction:-Along with growing Needs of electrical energy that continues to increase, if it can not be met will cause the supply of electrical energy is disrupted.Development of national roads is done to meet the needs of the community to drive. With the growth of national roads in North Sumatera, the need for electrical energy for street lighting is also increasing. Street lighting is used at night while at the same time there is a peak load on the power system. With the addition of this national road segment, a strategy is needed in the utilization of electric energy for street lighting. To meet the needs of electrical energy can be done with energy efficiency and energy saving done by adding equipment to improve the power factor [1]. Can also be done by decreasing active power losses and reactive power losses in power distribution systems [2].Efficiency is one step in the implementation of energy conservation. Energy efficiency is an appropriate general term for using less energy to produce the same number of useful services or outputs. In the general public, sometimes energy efficiency is also defined as energy saving. Energy efficiency is an action of energy utilization that is smaller than energy that should be used at a level of equal energy production. Energy efficiency occurs on the consumer side associated with the use of electrical equipment. Through energy efficiency measures will be achieved significant energy conservation. Energy conservation can be achieved through systematic, planned, and integrated Corresponding Author:-Janter. Address:-Study Program of Natural Resources Management and Environment, Postgraduate School, University of Sumatera Utara.