Indonesia is a country that is geographically located right in the equator and variously advantage and the wide for the use of solar energy. Indonesia has a relatively high radiation level, which is 4.80 kWh / m2 / day. Cemara Island is a tourist place but does not have electricity from PLN because access to its location is still difficult to reach. So from that chosen the planning system for the use of electrical energy using solar energy as the main electricity generation on the island. However, technical and economic analysis is needed so that the estimated weaknesses of the off-grid solar system can be estimated so as to reduce the risk of losses.

Testing of each component in the Solar Power Plant system also needs to be done to determine the condition and quality of the components to be used. Tests carried out include using solar panels, batteries, and inverters. Tests on solar panels are carried out within 2 days from 06.00AM - 18.00PM and data are taken per hour. The number of solar panel capacity is 8 x 150 Wp, solar charge controller of 40 A, 4 units of battery with 100 Ah specifications, and 2000 Watt of an inverter. All DC voltage systems are working at 12 V.

The economic analysis of the Cemara Island Solar Power Plant system with an initial investment of Rp 52,553,000, in scenario 1 uses interest at 6%, then in scenario 2 without using interest. Through calculations by looking for the value of COE (Energy Cost), NPC (Net Present Cost) and BEP (Break Even Point), so that costs can be calculated by the manager with the number of 11 managers per month