Integration of Earth to air heat exchnager was carried out at numerous places all over the world. The under ground Earth has about 25 degree celcius temperature (or annual average ambient air temperature of place) at 4 m depth for New Delhi composite climate in India. This natural resource useful for heating and cooling in winter and summer respectively. Skylight useful for daylighting of curved roof surfaces such as temples, monuments, malls etc. The natural north roof lighting saves considerable ammount of artificial lighting energy, low glare, gives better color rendering and pyschological comfort. The design of electrical load for home can be appropriately managed and operated using solar photovoltaic. Its daytime utility has been growing at many places all over the world buildings where it is operating during day and cutting the cost for battery bank for night load. The disadvantage is that it fails if grid power fails as solar photovoltaic power is directly connected to grid by power conditioning unit. The design of photovoltaic unit with battery bank, solar geometry, periodic function, programs and passive buildings concepts are narrated in this book.