The famous astronomer and educator Carl Sagan once said, “If you wish to make an apple pie from scratch you must first invent the universe.” What Sagan was pointing at is the fact that for us to really do anything from scratch, we have to understand the system in which we exist.

The planet and all its inhabitants exists as a massive, complex system of interconnected systems that we don’t always see. For example, the COVID-19 pandemic has clearly shown us that public health is part of a global web, inextricably linked. On a smaller scale, the materials and energy that we use to build and operate our homes and cities rely on these natural interconnected ecosystems. Effortlessly spanning scales from the level of the planet, a vast forest or a single home, the science of Systems Ecology provides a powerful perspective and valuable set of tools that can inform skillful design and construction practices for homes, buildings and cities.

How do natural ecosystems provide us with all that we need for our lives, homes and cities? What are the basic ingredients that are “cooked” in this recipe? Join Kristof as he interviews Miaomiao Hou and Dr. Bill Braham for a fast and furious dive into the infinite complexity of emergy. You’ll never be able to un-hear this. We will unpack some of the terms and concepts needed to unlock this powerful, versatile, quantitative way to understand what matters most when it comes to resources and energy, and why. Along the way we will learn about energy that remembers where it comes from and the layers of transformations it goes through along the way to us, so we can make better decisions on how to use it wisely.

Miaomiao Hou

Miaomiao Hou, a PhD candidate in architecture, is currently a visiting scholar at the Weitzman School of Design, specializing in environmental performance. Her recent research centers on computation and thermodynamics in architecture.

Dr. William Braham

William W. Braham, PhD, FAIA is a Professor of Architecture at the University of Pennsylvania, where he previously served as Chair, and is currently Director of the Master of Environmental Building Design and of the Center for Environmental Building + Design. He has worked on energy and architecture for over 30 years as a designer, consultant, researcher, and author of numerous articles and books.

His books include:
Architecture and Systems Ecology: Thermodynamic Principles for Environmental Building Design (Routledge, 2016)
Energy Accounts: Architectural Representations of Energy, Climate, and the Future (Routledge, 2016)
Architecture and Energy: Performance and Style (Routledge, 2013)
Rethinking Technology: A Reader in Architectural Theory (Routledge, 2007).

His recent articles include:

Braham, William. 2020. "Searching for a “Bioclimatic Law” in Architecture: Comfort and the Ethics of (Human) Performance." In The Routledge companion to paradigms of performativity in design and architecture, edited by Mitra Kanaani. New York: Routledge.

Braham, William W., and Jae Min Lee. 2020. "Metabolism of Urban Location: Travel Time and the Morphology of Cities." Frontiers in Sustainable Cities 2. doi: 10.3389/frsc.2020.00004

Lee, Jae Min, and William W. Braham. 2020. "Measuring public service quality: Revisiting residential location choice using emergy synthesis of local governments in Pennsylvania." Cities 102:102753. doi: https://doi.org/10.1016/j.cities.2020.102753.

Braham, William W., Jae Min Lee, Evan Oskierko-Jeznacki, Barry Silverman, and Nasrin Khansari. 2019. "Spatial concentration of urban assets in the Philadelphia region: An emergy synthesis." Ecological Modelling401:52-68. doi: https://doi.org/10.1016/j.ecolmodel.2019.03.016.

Braham, William W. “Regenerative Architecture,” 2019. Sustainability is Dead: Re-generation in Architecture. School of Architecture, edited by Richard Graves. University of Minnesota.

Braham, William W. “Cities are Grown in Soil,” 2018. In Ecology+Design Strategies to Solve Complex Problems. Pennsylvania State University.

Shen, Pengyuan, William Braham, Yunkyu Yi, and Eric Eaton. 2019. "Rapid multi-objective optimization with multi-year future weather condition and decision-making support for building retrofit." Energy172:892-912. doi: https://doi.org/10.1016/j.energy.2019.01.164.

Shen, Pengyuan, William Braham, and Yunkyu Yi. 2019. "The feasibility and importance of considering climate change impacts in building retrofit analysis." Applied Energy 233-234:254-270. doi: https://doi.org/10.1016/j.apenergy.2018.10.041.

Lee, Jae Min, and William Braham. 2019. "Right-Sizing Cities for Maximum Power: Urban Form Parameters for New York City and the Greater Philadelphia Region." Sustainability 11 (8):2352. doi: 10.3390/su11082352

Yi, Hwang, Ravi S. Srinivasan, William W. Braham, and David R. Tilley. 2017. "An ecological understanding of net-zero energy building: Evaluation of sustainability based on emergy theory." Journal of Cleaner Production 143:654-671. doi: https://doi.org/10.1016/j.jclepro.2016.12.059.

Shen, Pengyuan, William Braham, and Yunkyu Yi. 2018. "Development of a lightweight building simulation tool using simplified zone thermal coupling for fast parametric study." Applied Energy 223:188-214. doi: https://doi.org/10.1016/j.apenergy.2018.04.039.

Yi, Hwang, William W. Braham, David R. Tilley, and Ravi Srinivasan. 2017. "A metabolic network approach to building performance: Information building modeling and simulation of biological indicators." Journal of Cleaner Production 165:1133-1162. doi: https://doi.org/10.1016/j.jclepro.2017.07.082.

Yi, Hwang, William W. Braham, David R. Tilley, and Ravi Srinivasan. 2017. "Measuring ecological characteristics of environmental building performance: Suggestion of an information-network model and indices to quantify complexity, power, and sustainability of energetic organization." Ecological Indicators83:201-217. doi: https://doi.org/10.1016/j.ecolind.2017.07.056.

Lee, Jae Min, and William W. Braham. 2017. "Building emergy analysis of Manhattan: Density parameters for high-density and high-rise developments." Ecological Modelling 363:157-171. doi: https://doi.org/10.1016/j.ecolmodel.2017.08.014.

Yi, Hwang, Ravi S. Srinivasan, and William W. Braham. 2015. "An integrated energy–emergy approach to building form optimization: Use of EnergyPlus, emergy analysis and Taguchi-regression method." Building and Environment 84:89-104. doi: https://doi.org/10.1016/j.buildenv.2014.10.013.

Yi, Hwang, and William W. Braham. 2015. "Uncertainty characterization of building emergy analysis (BEmA)." Building and Environment 92:538-558. doi: https://doi.org/10.1016/j.buildenv.2015.05.007.

Srinivasan, Ravi S., William W. Braham, Daniel E. Campbell, and Charlie D. Curcija. 2012. "Re(De)fining Net Zero Energy: Renewable Emergy Balance in environmental building design." Building and Environment 47:300-315. doi: https://doi.org/10.1016/j.buildenv.2011.07.010.

Emergy

Emergy is the availability of energy (exergy) of one kind that is used up in transformations directly and indirectly to make a product or service. The unit of emergy is the emjoule, a unit referring to the available energy of one kind consumed in transformations. For example, sunlight, fuel, electricity, and human service can be put on a common basis by expressing them all in the emjoules of solar energy that is required to produce each. In this case, the value is a unit of solar emergy expressed in solar emjoules (abbreviated sej). Although other units have been used, such as coal emjoules or electrical emjoules, in most cases, all emergy data are given in solar emjoules.

Howard Odum

Howard T Odum was an American ecologist. He is known for his pioneering work on ecosystem ecology, and for his provocative proposals for additional laws of thermodynamics, informed by his work on general systems theory.

Land development in an urban megalopolis: A holistic environmental assessment of housing on Chongming Eco-island, China

A paper authored by our guests, Miaomiao Hou and William W.Braham

Abstract

Over the last decade, the Chinese government has promoted Chongming Eco-Island as an example of sustainable urbanization and a means to mitigate the growth of residential districts within the Shanghai megalopolis. With the immense urbanization pressure of a growing city, we ask “what is an appropriate type and scale of housing for land development on Chongming?” This study uses the method of emergy (with an “m”) synthesis to prepare a holistic assessment of the housing on Chongming, accounting for all renewable, non-renewable and imported resources used as well as greenhouse gas (GHG) emissions during building's life cycle stages. To overcome the lack of unit emergy values (UEVs) of building materials used on Chongming, this study first developed a method to derive accurate UEVs of local materials from a regional life cycle inventory (LCI) database. With Chongming Eco-Island as a case study, four typical residential housing types (farmhouse, single-family house, slab housing, high-rise apartment) were classified according to site density, the structure and floor area ratio (FAR) of buildings. Results indicate that slab housing with FAR as 3.1 contributes most to the total emergy and GHG emissions per building area, while it proves to have the highest environmental performance when taking into account the residential density. In this respect, high-rise apartments are not the optimum options for the overall sustainability of Chongming Eco-Island.

Emergy Diagram Example

Team

Hosted by Kristof Irwin
Edited and Produced by M. Walker

The Building Science Podcast

Energy With Memory