Buildings use around 30% of the world’s energy and cause about 28% of global CO₂ emissions, mainly due to heating and cooling. As cities grow and the climate warms, it’s more important than ever to make buildings energy-efficient. That’s where building energy models (BEMs) come in — they help us design buildings that use less energy.
To make these models more accurate, you can now combine them with ENVI-met, a tool that simulates the local microclimate around buildings. This article explains how adding ENVI-met data to tools like EnergyPlus, IES-VE, and TRNSYS can improve your energy simulations.
Fig. 1: ENVI-met enables users to create 3D models of urban landscapes, incorporating buildings, natural and artificial surfaces, vegetation, and water features.
Traditional building energy simulation (BES) tools rely on standardized weather station datasets (e.g., TMY, IWEC, EPW files) to define key boundary conditions such as air temperature, solar radiation, and wind speed. These inputs are essential for predicting heating, cooling, and ventilation loads. However, the generic climate files these standardized datasets contain fail to capture local microclimatic variations, leading to discrepancies between simulated and actual building performance.
ENVI-met helps generate precise input data for building energy simulations. The key benefits of using this data include:
Accurate outdoor air temperature inputs: ENVI-met simulates high-resolution, localized air temperature data, replacing generic climate files for more precise modeling.
ENVI-met simulates high-resolution, localized air temperature data, replacing generic climate files for more precise modeling. ENVI-met enables easy analysis of air, surface, and façade temperatures across different urban and meteorological conditions (See figure below).
ENVI-met simulates both longwave and shortwave radiation fluxes in urban environments with high resolution. This allows for precise calculations of radiative loads on building façades based on orientation, shading, and the surrounding urban context. High-resolution radiation flux calculations help determine external building energy loads (see figure below).
By capturing complex wind variations in urban areas, ENVI-met provides a more accurate assessment of ventilation effects on buildings. With computational fluid dynamics, ENVI-met enables wind simulations at resolutions as fine as 1 meter (see figure below).
As a holistic model, ENVI-met accounts for urban vegetation’s role in shading and transpiration, which significantly influences local microclimates. ENVI-met provides a detailed view of how vegetation impacts urban spaces and buildings (see figure below).
ENVI-met is a high-resolution microclimate simulation tool that enhances building energy models with localized environmental data. By integrating ENVI-met with Building Energy Simulation (BES) tools like EnergyPlus, IES-VE, or TRNSYS, designers can make informed decisions tailored to specific urban conditions.
From assessing urban heat island effects and optimizing façade radiation exposure to evaluating site-specific wind and ventilation strategies, ENVI-met refines energy simulations beyond standard climate files. This enables architects and engineers to design energy-efficient buildings that reduce operational energy demand while improving occupant comfort.
For more information on how ENVI-met can support healthier urban design, visit ENVI-met from One Click LCA.