A Computer Generated Visual Design & Planning Tool for Solar Energy Access - Phase I  

Project Title: A computer generated visual design and planning tool for solar energy access - phase 1

Applicant: The University of Hong Kong

Total Approved Grant: $750,000 (Actual Expenditure: $724,701.74)

Duration: 1.5.1998 - 30.4.1999

Project Status/Remarks: completed

Scope: This project commenced in May 1998 and is the development of a programme initiated in the Dept of Architecture, HKU. Early work is the translation of the first programme from Silicon Graphics system to PC platform to facilitate the programme's application and use to the wider design community. Programme development work is based on existing Hong Kong re-development sites and the impact of current building regulations on the density and solar access that this generates. The project aims to create a visual design and planning tool to enable the detailed investigation of the impact of solar energy on the building itself - at design stage - and to allow assessment of the impact of proposed new buildings on the surrounding neighbourhood.

Summary of the Findings/Outcomes:

A computer generated programme has been developed as a design and planning tool for the analysis of a building's solar access in the high-rise, high-density context of Hong Kong. The programme is interactive and allows the user to assess the solar radiation received on the envelope of the building both visually, in graded colours, and numerically, with an energy rating. The use of ray-tracing techniques and the visual devices of "blocked" and "un-blocked rays" reveals the impediments to solar access and facilitates the assessment of a proposed design's solar impact on its built surroundings. Alternative designs can be compared visually and numerically through its interactive features. The programme's intention is to provide a means of assessing the positive aspect of solar radiation as an energy asset, of evaluating appropriate surfaces for photovoltaic (PV) installations, and as the basis for local planning and solar access legislation.

Developed for pc use, the programme requires Internet Explorer of Netscape Communicator as operating platform; the output information is relative to the quality of input solar radiation and weather data. The programme's algorithms allow for any other weather data to be substituted. Any design developed as a simple 3-D geometric model (3-D Studio) can be imported given reasonable CAD support. Computation time for calculations and rendering depends on the speed/memory of the PC used and the relative complexity of the 3-dimensional design and can vary between a few minutes and over 1 hour. The preview setting allows a speedy but coarser view of the rendering.