Analysis of the energy needs of a tourist complex after renovation Razika Kharchi (1,*) , AEK.Hamid (2) , Meriem Chabane (2) , Khaled Imessad (1) , Sabrina Sami Mecheri (1) (1) Centre de developpement des energies renouvelables, CDER, BP62, Route de l’observatoire, 16340 Bouzareah, Alger, Algerie. (2) Département des Energies Renouvelables, Faculté des Sciences et de l’Ingénieur, Université Saad Dahleb de Blida, Algerie. e-mail : r.kharchi@cder.dz Abstract: Tertiary habitat is the largest consumer of energy sector in Algeria. This corresponds to almost 41% of national consumption. Final consumption in the residential sector reached 6 million tep in 2005. In this article, the results are analyzed after renovations made on a bungalow tourist complex located in Hammam Righa (100 km southwest of Algiers). The most important aspects for better energy performance of a building have been considered in this project. The calculations of thermal balances are made under the RETA software, according to the standards of the technical document DTR (C2-3), modeling the type of bungalow 5.5 using TRNSYS17 software. The results obtained show that after renovation of the bungalows, ambient temperatures are between 15 ° C and 20 ° C in winter and 25 ° C to 30 ° C in summer. Keywords: energy saving, heat loss, building renovation, RETA software, Trnsys, thermal comfort. Introduction Tertiary habitat is the largest consumer of energy sector in Algeria. This corresponds to almost 41% of national consumption. Final consumption in the residential sector reached 6 million tep in 2005[1]. Enforcement of legislation on the thermal regulation of buildings (DTR) remains difficult. Studies and analyzes were made on the energy consumption of residential housing, we cited some examples. Simulation of the energy performance of residential buildings in southern Algeria Work has been done on improving the energy efficiency of residential buildings in southern Algeria, Biskra with a hot, dry climate [2]. The energy performance of the building was simulated with TRNSYS. Two building types were compared; one is considered a BR reference building and the other a BBC building low consumption with an insulated envelope (walls, windows and terrace). The simulation results show that the energy requirements of cooling building BBC are almost the third of those BR building and that the difference in Energetics IE intensity between the two buildings is of the order of 70.62 kWh / m². A simulation of the thermal behavior of a bungalow resort is made to sizing a geothermal heating system for these [3]. Therefore, the sized heating and selected meets the thermal requirements. The installation is designed in Hammam-Righa (Latitude = 36.19N, longitude = 2.14E, altitude = 750 m). Local heating consists of 16 pavilions made of 7 bungalows each, for a total of 112 bungalows to heat. Economically, the study allows to show the feasibility of a geothermal heating system for a local spa. Moreover, it is clearly demonstrated that the necessary investment can be recovered in less than four years of operation and without forgetting the savings in maintenance and operation. The realization of this project opens up promising avenues for the future in the use of geothermal energy and enhancement of geothermal field in Algeria this in the field of home heating. The heating and cooling energy consumptions for houses located in Algiers are determined using the degree day method during one year[4]. Analytical results are validated by simulation with TRNSYS software. The degree day method proved to be applicable to the monthly and annual energy analysis for buildings. In Algeria, the summer season is more important than the winter season. heating requirements are twice the cooling needs in the home.. Energy consumption for heating reaches 670 kWh, as for cooling it is 1700 kWh. This article presents the results of an experimental study on a prototype dwelling [5], energy efficient, and equipped with an innovative heater. The device is a combined solar system which, through solar collectors, heat the home and produce domestic hot water. Heating the housing is through the floor. This project aims to design, construction and testing of a complex of bungalows heating system Hammam Chellala (Guelma)[6].The experimental part consists of immersing the heat exchangers in a well insulated hot water tank. Therefore the heat is transmitted from the hot fluid to the fluid which