The talk focuses on tools developed for enhanced understanding and visualization of spatial and temporal variations in carbon emissions, as an aid to accelerate decarbonization. The spatial variations are primarily due to the regional differences in fuel mixes at the electricity grid. The temporal variations are due to misalignment in trends for peak emissions with the trends for peak load at a building level and/or peak utility time-of-use rates.

The first part of the talk would focus on a Python-based methodology developed using IES VE’s Python API and NREL’s Cambium dataset to calculate hourly operational carbon emissions based on the project location and visualize them against energy use data. The visuals help understand the variances in peak times for energy use against carbon emissions, as well as source and end use breakdowns for both the metrics. It also allows for comparing the emissions calculated using hourly emission rates from Cambium against annualized “flat” carbon emission rates published by the EPA or other. GHG emissions are more important than ever, but choosing the wrong metric could cause projects to implement strategies that produce more carbon during key time-of-use periods. The talk will feature project case studies where design decisions might be governed by carbon emissions over energy use or utility costs, or even the type of carbon emissions metric.

The second part of the talk would address a script developed to calculate percentage improvement of proposed performance over an ASHRAE Standard 90.1 PRM Baseline model per LEED Pilot ACP EApc95, Alternative Energy Performance Metric. This script, also developed using IES VE’s Python API, extracts the source-breakdown of the energy consumption for the Proposed and Baseline models. It quantifies the savings/performance improvement based on the metrics of cost, source energy, greenhouse gas emissions and time dependent valuation (TDV) energy (for projects in California). It averages the percent savings of the two highest-performing metrics using equal weighting to determine overall savings percentage. The talk will highlight case studies of projects that have been able to claim greater savings & receive higher LEED points by leveraging this script, which makes the calculations across various metrics for LEED Pilot ACP EApc95 super quick and effortless.

Both of these Python-based workflows help to understand and compare building performance metrics used commonly in the industry today. They will highlight project case study examples to demonstrate the usefulness of the output visualizations and reports. The talk will also summarize the process used to develop the workflows and some of the pitfalls and lessons learned along the way.

The global push towards a sustainable future necessitates transformative measures to mitigate carbon emissions in existing structures to implement regenerative design strategies. This presentation focuses on the imperative role of decarbonization in curbing energy consumption and embodied carbon in buildings, with a case study illustrating its practical implementation.

In sustainable design, it’s been said the most sustainable building is one that already exists. When an existing structure is considered for a change in use, especially for education, evaluating what has value to keep and reuse can be quite complex. Using a compelling case study of an educational building retrofit, this session delves into the multifaceted strategies employed to achieve net-zero carbon emissions. The case study showcases the integration of how operational Carbon & Embodied Carbon are involved in this process. Different strategies from renewable energy sources, advanced insulation techniques, and material reuse are used to significantly reduce operational energy intensity and embodied carbon throughout the building's lifecycle to make the building act Regeneratively. The project uses an existing building core & structure to meet the client's desires.

Detailed Embodied Carbon model, using Tally & one-click LCA, helped the design team decide on what materials to use for the envelope & interior to mitigate the embodied carbon intensity for this project's Whole Building Life Cycle Analysis (WBLCA). Also, this project has a new addition that uses regenerative strategies to reduce the carbon footprint of the structure & envelope.

On the other hand, Major HVAC renovation & enhanced thermal strategies for the envelope play a critical role in reducing the operational carbon of this project. This project proposed using PV systems for the roof and site, making the net zero carbon approach amazingly meet.

This session aims to inspire the adaptive reuse design story of a site with two former auto dealership buildings to be transformed into a new career and technical education hub. Also, it will empower attendees with practical knowledge and tangible examples, fostering a deeper understanding of the transformative potential of decarbonization in existing buildings and ultimately steering us closer to a sustainable and carbon-free built environment. Using different regenerative strategies.

In this presentation, we will explore the significance of adding hourly carbon analysis to the standard building efficiency conversation. Emphasizing the critical role of hourly carbon factors, we delve into the impact of energy and carbon savings of various technologies and how they affect project goals, particularly decarbonization goals. The presentation will discuss the influence of perceived performance of building improvements, scrutinized through hourly carbon emissions. We address the challenges faced by professionals in adapting their understanding of building technologies across various climatic and operational contexts. By layering hourly carbon analysis results, more complex, nuanced, but wholistic decision making can occur. This presentation aims to enhance understanding of the intricate relationship between building performance and hourly carbon emissions, contributing to the development of more sustainable and efficient buildings.

Currently, cities are responsible for 70% of global carbon emissions. As urban areas continue expanding to accommodate rapid population growth, quantifying, and reducing greenhouse gas emissions associated with urban development is crucial for climate change mitigation.

To identify environmental impacts across built systems, a Life-Cycle Assessment (LCA) is an identified and widely adopted methodology. However, LCAs have been used to quantify the carbon footprint of primarily individual buildings in recent years, and not for evaluating entire urban areas, especially during early planning phases when impactful design decisions are made with low repercussions on the project cost. Developing ways to integrate LCAs with urban design can provide this data-driven guidance to reduce emissions from neighborhood-scale projects.

As a part of a joint Henning Larsen and Ramboll research project, this research aims to advance low-emission urban design by developing an LCA-based parametric tool called Urban Decarb. The tool looks at the city as a whole and simulates the potential embodied (from materials) and operational (from energy use) carbon emissions of key urban components including buildings, parking, roads, bridges, green spaces, water systems, and energy networks. The tool is developed using the visual programming language Grasshopper, enabling integration with the 3D modeling software Rhinoceros commonly used by urban designers and architects.

With a basis in the standardized LCA methodology, a simplified parametric workflow for bottom-up inventory analysis is proposed. Replacement factors assess renovation and transformation versus new construction for existing buildings. The quantities are matched with a catalog of standardized components based on generic data, adhering to EN 15978's preference for concept stage LCAs. The catalog integrates the German Ökobaudat database for building emissions and the Danish InfraLCA database for open spaces. Operational energy is simulated using Ladybug Tools' Dragonfly plugin with simplified 2D geometries and dominant program types. A graphical interface visualizes outputs and the results are shown in a holistic combined functional unit with total emissions, emissions per floor area, and emissions per inhabitant.

Urban Decarb has been applied to several urban projects in Europe, including a residential neighborhood in Copenhagen. Through extensive timber construction and prioritizing landscape over hardscape, the tool showed a 34% reduction in emissions compared to a conventional baseline. This project successfully demonstrates the tool’s capabilities in assessing urban design alternatives and providing data-driven guidance to reduce a project's carbon footprint.

Although uncertainties remain high during initial planning phases, integrating carbon knowledge early allows urban development projects to align with local and global emission reduction goals. Urban Decarb advances this integration by modeling embodied and operational emissions across urban components through rapid scenario testing through a flexible parametric workflow. The tool is currently being expanded to include global databases on building emissions, climate properties, and economic parameters.

With the increasing pressure to reach net zero carbon by 2050, many designers are wondering how the greening grid will play into their projections. Fortunately, there are a number of data sources to choose from in the realm of predictive grid carbon intensity. From free data like Cambium, CRREM and eGRID, to paid options like WattTime, it can be hard to know where to start. Particularly since those options are poorly differentiated, and their methodologies are not clearly stated. This makes it difficult to feel confident in selecting one over the others. Especially when the results differ widely between data sets. There are several factors that designers might be interested in, such as the ability to model international scenarios, whether greenhouse gasses other than carbon dioxide are included, and what assumptions about future energy costs and regulations are, or are not, included. With so many projection models vying for our attention, it is imperative that designers parse out what data sets are most appropriate for which applications. In this presentation, key differences between and strengths of each data set will be discussed. Assumptions will be clearly summarized, and the implications of these inferences will be presented. Additionally, practical situations will be examined, and reasoning used to justify the selection of one data source over another, with real world examples. Finally, practical tips for talking with laypeople and other less technical stakeholders about grid carbon intensity projections will be shared.

This presentation discusses the process and outcomes of a detailed cradle-to-site A1-A5 Life Cycle Assessment (LCA), focusing on the embodied carbon of a Datacenter constructed in the US. Our approach goes further than the conventional architectural and structural components and delves into the often-neglected mechanical, electrical and plumbing (MEP) systems, challenging the standard approach of conducting LCA's for buildings (including for the requirements of building certifications).

The study, conducted over a 25-year lifespan, investigates the intricacies of a data center and highlights its unique design and subsequent environmental footprint. Noteworthy challenges encountered during the LCA, primarily the absence of product-specific EPDs for MEP systems, inspired the development of a comprehensive evaluation approach. This approach involves the use of EPD Representativeness (EPD-Rep) and qualitative assessments to derive reliable data for estimating the embodied carbon of mechanical and electrical equipment.

The following discussion will unfold the project team's efforts to compare and reconsider various facets of the LCA results:

1. Comparison with Other Building Types:

The data center LCA results reveal a high value of embodied CO2e emissions. Notably higher than comparable results in other building types, this finding prompts an in-depth exploration of the distinctive characteristics of data centers.

2. Architectural and Structural vs. MEP Systems:

In a departure from typical building types, our LCA results highlight a paradigm shift. Combined MEP systems contribute the highest relative amount at over 43% of total emissions, surpassing architectural and structural components, which contribute 41%. This prompts a reevaluation of the traditional emphasis on structural elements in embodied carbon discussions.

3. Life Span Assumption Comparison: 60 Years vs. 20 Years:

Challenging the standard practice of assuming a 60-year life span for LCAs, our study highlights the complexity of implementing a shorter lifespan commonly seen for datacenters. At 25 years our study provided an optimistic scenario for equipment replacement, and highlights the need for a standardized approach. Furthermore, by comparing results under both 60 and 20-year scenarios, we uncover the substantial differences, questioning the appropriateness of conventional life span assumptions for data centers when conducting building assessments such as LCAs.

This presentation provides valuable insights derived from the examination of a US data center LCA. It aims to challenge existing norms and highlight the need for standardizations of LCAs and environmental assessments for industrial buildings, such as datacenters.

The idea started with our team working on an ambitious journey of decarbonization planning for two large office buildings. The process of such studies usually involves many data points; some from an energy model (EUI, operational cost estimates), some from public data (current emissions factors and projections) and energy conservation measure (ECM) cost data from a contractor. Then there are project specific realities such as tenant turnover timeline, capital projects cycle and capital projects phasing that need to weave into a cohesive roadmap for clients. The complexity of such projects fundamentally lies in a lack of a uniform data input and calculation structure that, in our experience, results in “slightly” different spreadsheet calculations for each project. The problem with this approach is hardship in repeatability with data input and calculations that are “templatized” and automated.

This is a gap that some software developers are trying to fill with expensive subscription-based approaches that at their core seem like “glorified spreadsheet calculations”. These software usually require input from an energy model estimate of ECMs’ energy reduction percentages, ECM upfront and operation & maintenance (O&M) costs, client’s utility prices and escalation rate assumptions and many more inputs that practitioners often find key parameters from a specific project may not fit the design of a particular software design. Aa a result, project-specific spreadsheet calculations prevail.

This presentation showcases our attempt to design a general use decarbonization planning tool in MS PowerBi that is web-based, relatively low-tech and is built on the backbone of many (messy) spreadsheet calculations done on previous projects. The goal was to capture as many public databases available for decarbonization planning, make the public data capture as automated as possible (with APIs), create typical data input fields such as base building information, name and number of ECMs, percentage energy and carbon improvements from ECMs, ECM capital and O&M costs and the timeline of implementation of ECMs. The final product is meant to be repeatable for general use projects, templatized and ideally published on the web for others to use as an open-source and low-tech tool on projects. The limitations and success of the tool will be discussed in addition to a brief summary of commercially available tools in the marketplace to perform similar calculations.

This presentation will introduce a method to investigate the economic impacts of ETS on building retrofits. The reduction of the payback period and the increase of the return on investment are adopted as evaluation metrics. This presentation will show the results of medium office buildings at four locations in the U.S.