Early Design Stages
A Holistic and Parametric Approach for Life
Cycle Assessment in the Early Design Stages
Diego Apellániz1, Panu Pasanen2, Christoph Gengnagel1
1B+G Ingenieure Bollinger und Grohmann GmbH Universität der Künste Berlin Berlin, Germany
2Bionova Ltd. Helsinki, Finland
Figure 1. UI of the Plugin for Rhino of One Click LCA.
This paper presents an approach for implementing life-cycle assessment (LCA) in the early design stages of a building project based on the new plugins for Rhino and Grasshopper of One Click LCA, which aims to contribute to fight climate change from within the construction industry.
Figure 2. Workflow diagram of a LCA with the Grasshopper plugin of One Click LCA.
These new tools developed by Bollinger + Grohmann in collaboration with Bionova Ltd. combine the extensive environmental database of One Click LCA with a user-friendly interface and an object-oriented structure to provide parametric and holistic LCA within the environment Rhino + Grasshopper.
A case-study of the implementation of this tool in the design phase of an office building complex in Berlin is also included to illustrate new possible workflows in the early design stages regarding comparison of embodied energy of design alternatives, automatic LCA from architectural and calculation models, optimization processes based on global warming potential (GWP) and environmental benchmarking.
Figure 3. Results visualization of LCA with the “Visualize Results” component of the Grasshopper plugin of One Click LCA.
With more than 30 % of global carbon dioxide emissions, the construction and building materials sector is the biggest driver of global climate change. The current world climate report of the International Panel on Climate Change (IPCC) underlines the absolute necessity for an immediate rethink and the readiness to implement existing solutions in the short term. The goal of this radical change is a drastic reduction of the grey energy contained in new buildings and the associated reduction of CO2 emissions.
Figure 4. Aerial render of the office complex in Berlin, Germany © Thomas Hillig Architekten GmbH.
At the same time, the enormous resource consumption of current construction, especially in the area of mineral materials, requires a rediscovery of material-saving construction that is oriented towards the basic concepts of material effectiveness, robustness, structural diversity and the use of local resources. The use of materials based on renewable raw materials should be a priority.
Figure 5. Systems and assemblies of the database combine different structural and non-structural materials.
In order to effectively fight climate change from within the construction industry, an adequate metric must be implemented from the very beginning of the design stage to positively affect the environmental outcome of a construction project.
Life-cycle assessment (LCA) is arguably the most extended objective methodology for evaluating the environmental impact of products, processes and services which can also be applied to evaluate the environmental impact of a certain building.
Figure 7. Distribution of embodied carbon among the different building elements.
The plugin for Rhino is particularly intended for designers who might not be advanced users of the parametric environment, but can anyway benefit from a geometrical 3D model to automate estimation of material quantities for a LCA.
Figure 8. Minimization of building embodied energy with Karamba, Galapagos and the Grasshopper plugin of One Click LCA.
This tool does not only accomplish this, but it also provides functionalities for mapping material environmental profiles, including EPDs, to the geometric objects of the Rhino model by grouping them according to their corresponding model layer and also by implementing certain filter options related to the material properties of the EPD database. The final step is to export the list of materials to the cloud service of One Click LCA through the API.
Figure 10. Real time environmental impact analysis from a structural calculation model with the Parametric FEM Toolbox and the Grasshopper plugin of One Click LCA.
The plugin components were compiled using the same GUI widgets as the Karamba plugin. They provide Grasshopper components with additional functionalities such as extendable menus, dropdown lists, checkboxes, etc. and are ideal to manage objects with multiple properties in the Grasshopper environment.
Also, tooltips were implemented to select LCA Profiles with particularly long names from the dropdown menus of the “Select LCA Profile” component. The “Calculate LCA” component has two outputs. The first one includes all the Constructions with environmental results so that they can be analyzed either graphically with the “Visualize Results” component or numerically with the “Disassemble” components.
The second output provides the numerical result of the embodied carbon of the building (kg CO2-equivalent emissions). These results make reference to the stages A1-A3 (manufacture stage) of a life cycle analysis. If a more thorough LCA was, the user should choose the option “LCA in Cloud” to import the Constructions to the web platform of One Click LCA similarly to the Rhino plugin and calculate the LCA there.
Figure 9. Multi-objective optimization with Octopus and One Click LCA.
The new plugins for Rhino and Grasshopper of One Click LCA have proven to have the potential to enhance the early stages of the design phase by providing the design team with a workflow for efficiently and accurately implementing LCA in the design phase.
They improve current parametric strategies to reduce building embodied carbon in early design stages by implementing a more extensive construction materials EPD database in the Rhino + Grasshopper environment, by providing an user-friendly interface and an object-oriented structure, by adding automatic result visualization options and by enabling an export process to the web platform for additional verifications and comparison with benchmark projects.
Figure 11. Rhino 3d model of the office building for LCA.
These tools aim at encouraging designers, who might not even be advanced Rhino and Grasshopper users, to implement LCA in their designs also for projects that are not explicitly asked to obtain a green certification and thus fight climate change from within the building industry. Furthermore, their ease of use and pedagogic graphic results make them appropriate for introducing them into the education system to raise environmental awareness among the next generation of architects and engineers.