The first Zero Energy Building (ZEB) in South-east Asia was retrofitted from an existing building (2009) in Singapore. Converted from a three-storey former workshop, ZEB houses offices, classrooms and a resource centre. The ZEB is a zero energy building because the building produces enough energy to run itself. As a critical test-bed facility, the 4,500 m2 building produces enough energy to power the building. In all, the building will save S$84,000* a year in energy cost compared to typical office in Singapore. The building aims to achieve this through a combination of green building technology, clever building design that takes advantages of natural ventilation and lighting (this is called ‘passive design’), and the hamessing of solar energy.