Izmir Institute of Technology (IZTECH), founded in 1992, is the third state university of Izmir. The campus area has the renewable energy sources of several kinds. The aim of this thesis is to design and optimize a building, which produce its own energy by using these sources.Gülbahçe Zero Energy Building (GUZEB) is designed as a library and a gallery, and to be used for symposiums and special day meetings. 32oC geothermal water that is from the ancient cave, which is located in campus area and close to the location of the building, will be used for heating and to meet the hot water requirement of the building. Floor heating system considered being the best heating option with 32oC water source. Necessary pipe length for floor heating system is found by using the software FLUENT.Necessary cooling load is calculated in two different ways by with and without hourly load distribution. With hourly load distribution cooling load calculation is made by using Alarko-Carrier .s HVAC Design Hourly Analysis Program.Additionally, energy storage method is recommended for the cooling plant, which will meet the cooling load. With this method, smaller cooling plant can be chosen instead of choosing cooling plant, which meets the load of symposium days or special day meetings that both are rare. Because of this, electrical load of the cooling plant considered to be lower.Silica-aerogel and many different isolation materials are used in the design of building.s isolation. Fiber lighting is recommended to decrease the lighting load of the building and with automatic controlled curtains and panels; daylight can be controlled during the summer days. So, electric consumption of the building can be tried to be decrease. The wind speed of the location is 5-7 m/s. Electric demand can be met with the photovoltaic panels and wind turbine that will be located in suitable position.