Integrated canopy, building energy and radiosity model for 3D urban design

TL;DR

This paper introduces an integrated 3D urban model combining canopy, building energy, and radiosity simulations to optimize urban morphology for energy efficiency and climate impact.

Contribution

It presents a novel integrated 3D modeling framework for urban design that links morphology, energy, and climate effects with simple parameters.

Findings

Careful 3D morphology design can halve heat demand.

Higher surface/volume ratio improves energy efficiency.

Urban morphology significantly impacts insolation and climate.

Abstract

We present an integrated, three dimensional, model of urban canopy, building energy and radiosity, for early stage urban designs and test it on four urban morphologies. All sub-models share a common descriptions of the urban morphology, similar to 3D urban design master plans and have simple parameters. The canopy model is a multilayer model, with a new discrete layer approach that does not rely on simplified geometry such as canyon or regular arrays. The building energy model is a simplified RC equivalent model, with no hypotheses on internal zoning or wall composition. We use the CitySim software for the radiosity model. We study the effects of convexity, the number of buildings and building height, at constant density and thermal characteristics. Our results suggest that careful three dimensional morphology design can reduce heat demand by a factor of 2, especially by improving insolation of lower levels. The most energy efficient morphology in our simulations has both the highest surface/volume ratio and the biggest impact on the urban climate.