-An area less than 5.5% of Egyptian territory is where most of Egypt's population lives. A narrow strip of land forms the Nile Valley and Delta sector.The National Project for Desert Hinterlands is one of the urban projects targeting rehabilitation of the poor in alternative villages in the near desert to stop urban sprawl over agricultural land and decrease congestion in the old habitats. Low cost energy efficient houses are the aim of the architect in similar projects taking in consideration the high electricity consumption of Egypt's residential sector.Based on a literature review, this paper presents a proposal for designing desert dwellings that accommodate the hot dry climate by incorporating passive elements and using stabilized earth blocks as a local building material. Furthermore, simulation is used to test alternative proposals. The results show that an underground constructed house with a sunken courtyard incorporating an Earth to Air Heat Exchanger System (EAHE) can reduce between 42-72% of energy consumption used to achieve thermal comfort compared to contemporary desert housing projects.

The main consumer of electricity in Egypt is the residential sector which accounts for 42% of the total consumption, followed by the industrial sector (28%). The consumption of the residential sector has been steadily increasing in the recent years. According to the Ministry of Electricity and Energy, this is due to two factors: the expansion of residential compounds and new communities as well as the use of domestic appliances, air conditioners in particular, during hot weather. Egypt is in a real need to change the "business-as-usual" approach in housing projects to overcome the major challenge of the hot dry climate while respecting the economic factors taking into consideration that increasing population and housing projects will affect negatively the energy demand in the coming few years. This paper will explore the main passive and hybrid design techniques for low cost energy efficient housing in hot arid climate. It will review six international case studies worldwide showing their energy efficiency practice and their methods to overcome climate and cost challenges using passive and hybrid techniques along with using local materials and renewable energy. The paper will recommend some of these techniques to be implemented in Egypt.