DAYLIGHT1-2-3 – A state-of-the-art daylighting/energy analysis software for initial design investigations

This paper provides an overview of Daylight1-2-3, a new daylighting/energy analysis software for design professionals and architectural students with an interest in daylighting and sustainable design, but no required previous knowledge of either daylighting concepts or simulations. The initial version of Daylight 1-2-3 focuses on private offices, open-plan offices, and classrooms. The paper describes the process that the tool’s development team went through to develop a common vision and requirement catalogue for Daylight 1-2-3 using both lessons learnt from previous software projects, as well as results from an online survey of mostly LEED Accredited Professionals. The requirement catalogue later helped the team to assemble a fast, state-of-the-art simulation engine: during a Daylight 1-2-3 simulation Radiance-based daylight coefficients are read into a customized version of  ESP-r. The version has been specifically tuned to model occupant behavior (SHOCC module), calculate the latest generation of dynamic, climatebased daylight performance metrics (DDS module), and run an annual fully integrated lighting/thermal simulation in about a minute. Venetian blinds are modeled through SkyVision correction factors.