Publications

Paper on The Economic Impacts of Carbon Emission Trading Scheme on Building Retrofits has been published in Building and Environment

Anonymous — Thu, 30 Jun 2022 19:46:14 +0000

Paper on The Economic Impacts of Carbon Emission Trading Scheme on Building Retrofits has been published in Building and Environment Anonymous (not verified) Thu, 06/30/2022 - 13:46

As a popular emission reduction tool, the carbon emission trading scheme (ETS) can potentially add an economic incentive for building owners to retrofit buildings in addition to the cost savings in energy. As a part of a comprehensive research project funded by US National Science Foundation, the Science Foundation Ireland, and the Department for the Economy in Northern Ireland, our team has investigated the additional economic benefits of building retrofits from carbon credits via the ETS. We found that carbon prices have significant economic impacts on building retrofits. With the relatively low forecasted time-variant carbon prices (around 10 USD per ton), the economic impacts of ETS on building retrofits are small. When carbon prices increase, the impacts of ETS would be up to 25% for 50 USD per ton (current prices in European Union) and 51% for 100 USD per ton.

This work has been published under the title “The economic impacts of carbon emission trading scheme on building retrofits: A case study with U.S. medium office buildings" in the journal Building and Environment. The full paper is available here.

The first author of this paper, Yingli Lou, is a Ph.D. student in the SBS lab, where her research focuses on large-scale building energy simulation and carbon emissions from buildings.

Congratulations to Yingli on publishing this paper!

Off

Traditional

White

Paper on Tradeoffs Among Indoor Air Quality, Financial Costs, and CO2 Emissions for HVAC Operation Strategies to Mitigate Indoor Virus in U.S. Office Buildings has been published in Building and Environment

Anonymous — Thu, 30 Jun 2022 19:38:39 +0000

Paper on Tradeoffs Among Indoor Air Quality, Financial Costs, and CO2 Emissions for HVAC Operation Strategies to Mitigate Indoor Virus in U.S. Office Buildings has been published in Building and Environment Anonymous (not verified) Thu, 06/30/2022 - 13:38

It is challenging to provide excellent indoor air environment, while saving operational cost and reducing CO₂ emission. In this work, we explored the tradeoffs among indoor air quality, financial costs, and CO2 emissions for HVAC operation strategies to mitigate indoor virus in U.S. office buildings. New evaluation metrics are created to consider the comprehensive impact of improving IAQ on costs and CO2 emissions, using dynamic emission factors for electricity generation depending on the location. HVAC operation strategies are studied in five different locations across the United States, with distinct climates and electricity sources. In four of the five locations, MERV 13 filtration offers the best improvement in IAQ per increase in costs and emissions relative to MERV 10. The exception is the mildest climate of San Diego, where use of 100% outdoor air provides the best IAQ with a limited increase in costs and emissions.

This work has been published under the title "Tradeoffs Among Indoor Air Quality, Financial Costs, and CO2 Emissions for HVAC Operation Strategies to Mitigate Indoor Virus in U.S. Office Buildings " in the journal Building and Environment. The full paper is available at this link.

The first author of this paper, Cary Faulkner, is a Ph.D. student in the SBS lab and his research interests include building system modeling, computational fluid dynamics, indoor environment modeling, and machine learning.

Congratulations to Cary on publishing this paper!

Off

Traditional

White

Paper on Evaluating Performance of Different Generative Adversarial Networks for Large-Scale Building Power Demand Prediction has been published in Energy and Buildings

Anonymous — Thu, 30 Jun 2022 19:21:47 +0000

Paper on Evaluating Performance of Different Generative Adversarial Networks for Large-Scale Building Power Demand Prediction has been published in Energy and Buildings Anonymous (not verified) Thu, 06/30/2022 - 13:21

How could we predict large-scale building power demand fast and accurately? Generative Adversarial Networks (GAN), as a potential candidate, have recently attracted a lot of attention. This paper identified five promising GANs (Original GAN, cGAN, SGAN, InfoGAN, and ACGAN) and evaluates their performance for predicting building power demand at a large scale. As a result, cGAN and Original GAN are recommended.

This work has been published under the title “Evaluating Performance of Different Generative Adversarial Networks for Large-Scale Building Power Demand Prediction” in the journal Energy and Buildings. The full paper is available here.

The first author of this paper, Dr. Yunyang Ye, is the former member of the SBS Lab. He is currently a Research Scientist at Pacific Northwest National Laboratory (PNNL). His research focuses on building energy modeling, building code and standards analyses, urban scale modeling, building-to-grid integration, and energy policies.

Congratulations to Yunyang on publishing this paper!

Off

Traditional

White

Paper on Fast and Accurate Modeling Approach for Water and Steam Thermodynamics with Practical Applications in District Heating System Simulation has been published in Energy

Anonymous — Thu, 30 Jun 2022 18:59:46 +0000

Paper on Fast and Accurate Modeling Approach for Water and Steam Thermodynamics with Practical Applications in District Heating System Simulation has been published in Energy Anonymous (not verified) Thu, 06/30/2022 - 12:59

Do you know that 97% of district heating systems in the US are steam based systems? However, we do not have Modelica models which can simulate such system effectively for practice. As a part of large collaborative research in developing URBANopt and Modelica Buildings library, we created a fast and accurate modeling approach for water and steam thermodynamics for real-world district heating system practice. This work presents a novel split-medium approach that implements numerically efficient liquid water models alongside various water/steam models, breaking costly algebraic loops by decoupling mass and energy balance equations. New component models for steam DH systems are also presented. The models are implemented in Modelica language and evaluated accuracy and computing speed across multiple scales: from fundamental thermodynamic properties to complete districts featuring 10 to 200 buildings. Compared to district models with the IF97 water/steam model and equipment models from the Modelica Standard Library, the new implementation improves the scaling rate for large districts from cubic to quadratic with negligible compromise to accuracy. For an annual simulation with 180 buildings, this translates to a computing time reduction from 33 to 1–1.5 h.

This work has been published under the title "A Fast and Accurate Modeling Approach for Water and Steam Thermodynamics with Practical Applications in District Heating System Simulation" in the journal Energy. The full paper is available here.

The first author of this paper, Kathryn (Katy) Hinkelman, is a Ph.D. student in the SBS Lab. Her research focuses on modeling and simulation of community-scale energy systems using Modelica language, including traditional district heating and cooling systems and innovative biomimetic (nature imitating) designs for future sustainable and resilient communities.

Congratulations to Katy on publishing this paper!

Off

Traditional

White

Paper on Carbon Emission Responsive Building Control has been published in Applied Energy.

Anonymous — Mon, 28 Mar 2022 19:10:13 +0000

Paper on Carbon Emission Responsive Building Control has been published in Applied Energy. Anonymous (not verified) Mon, 03/28/2022 - 13:10

This paper proposes a carbon emission responsive building control framework for controlling thermostatically controllable loads such as heat pumps and heat pump water heaters. The control decisions are made in response to the real-time grid carbon emission intensity signals to shift the loads from “unclean” hours to “clean” hours. The resulted energy consumption, energy cost, carbon emissions, and thermal comfort are compared for an all-electric residential community in Basalt, CO.

This work has been published under the title “Carbon Emission Responsive Building Control : A Case Study With an All-Electric Residential Community in a Cold Climate” in the journal Applied Energy. The full paper is available here.

Dr. Jing Wang, the first author of this paper and former member of the SBS Lab, successfully defended her PhD dissertation on “Occupant-centric Modeling and Control for Low-carbon and Resilient Communities” in September 2021. Dr. Jing Wang's research focuses on resilient energy systems, building energy system modeling and control, and building-to-grid integration. For more insight about Dr. Wang's scholarly work please refer to this page.

Off

Traditional

White

Paper on Modelica-based Modeling and Simulation of District Cooling Systems has been published in Applied Energy.

Anonymous — Wed, 16 Feb 2022 17:34:53 +0000

Paper on Modelica-based Modeling and Simulation of District Cooling Systems has been published in Applied Energy. Anonymous (not verified) Wed, 02/16/2022 - 10:34

While equation-based object-oriented modeling language Modelica can evaluate practical energy improvements for district cooling systems, few have adopted Modelica for this type of large-scale thermo-fluid system. In collaboration with LBNL and NREL through the URBANopt-Modelica project, this work is one of the first district cooling case studies to include hydraulics in piping networks alongside plant models featuring realistic mechanical systems and controls. For a real-world case study at the University of Colorado Boulder, we identified investment-free annual savings of 15% energy, 9% electricity cost, and 15% carbon emissions. The models used in the case study are open source released at the Modelica Buildings Library version 8.1.0.

This work has been published under the title “Modelica-based modeling and simulation of district cooling systems: A case study” in the journal Applied Energy. The full paper is available here.

The first author of this paper, Kathryn (Katy) Hinkelman, is a Ph.D. student in the SBS Lab. Her research focuses on modeling and simulation of community-scale energy systems using Modelica language, including traditional district heating and cooling systems and innovative biomimetic (nature imitating) designs for future sustainable and resilient communities.

Congratulations to Katy on publishing this paper!

Off

Traditional

White

Paper on Daily Power Demand Prediction for Buildings at Large Scale has been published in Building Simulation.

Anonymous — Tue, 08 Feb 2022 17:35:50 +0000

Paper on Daily Power Demand Prediction for Buildings at Large Scale has been published in Building Simulation. Anonymous (not verified) Tue, 02/08/2022 - 10:35

Large scale power demand prediction for buildings plays a great role in stable operation and management for the grid. To predict large scale power demand in an accurate and fast way, our team has developed a new method called E-GAN, which combines a physics-based model (EnergyPlus) and a data-driven model (GAN), to predict the daily power demand for buildings at a large scale.

This work has been published under the title "Daily power demand prediction for buildings at a large scale using a hybrid of physics-based model and generative adversarial network " in the journal Building Simulation. The full paper is availbale here.

The first author of this paper, Chenlu Tian, was a visiting Ph.D. scholar in the SBS lab, where her research focused on building data analysis using machine learning methods.

Congratulations to Chenlu on publishing this paper!

Off

Traditional

White

Paper on Long-term Carbon Emission Reduction Potential of Building Retrofits has been published in Building and Environment.

Anonymous — Mon, 03 Jan 2022 19:02:17 +0000

Paper on Long-term Carbon Emission Reduction Potential of Building Retrofits has been published in Building and Environment. Anonymous (not verified) Mon, 01/03/2022 - 12:02

Buildings account for approximately 36% of the United States’ total carbon emissions and building retrofits have great potential to reduce carbon emissions. As a part of a comprehensive research project funded by US National Science Foundation, the Science Foundation Ireland, and the Department for the Economy in Northern Ireland, our team has investigated the emission reduction potential of building retrofits in the next 30 years considering the era of increased renewable power generation. Based on our study, it is recommended that the retrofits of medium office buildings in the U.S. should focus on: 1) improving lighting and equipment efficiency; 2) locations with higher coal usage rate, and 3) buildings under the high renewable cost scenario.

This work has been published under the title “Long-term carbon emission reduction potential of building retrofits with dynamically changing electricity emission factors" in the journal Building and Environment. The full paper is available here.

The first author of this paper, Yingli Lou, is a Ph.D. student in the SBS lab, where her research focuses on large-scale building energy simulation and carbon emissions from buildings.

Congratulations to Yingli on publishing this paper!

Off

Traditional

White

Paper on Assessing the Performance of Portable Air Cleaners in a Conference Room has been published in Building and Environment.

Anonymous — Thu, 09 Dec 2021 21:21:14 +0000

Paper on Assessing the Performance of Portable Air Cleaners in a Conference Room has been published in Building and Environment. Anonymous (not verified) Thu, 12/09/2021 - 14:21

The COVID-19 pandemic has highlighted a need for strategies to mitigate the risk of airborne disease transmission in shared indoor spaces. In an effort to better understand indoor airborne contaminant transport funded through DTRA and in partnership with LBNL, this work presents a methodology for simultaneously simulating aerosol dispersion from multiple source locations in CFD and metrics for assessing the in-room performance of different ventilation strategies. Using these methods engineers can efficiently assess the performance of different ventilation strategies at removing contaminants from the occupied region of the room.

This work has been published under the title “Assessing the Use of Portable Air Cleaners for Reducing Exposure to Airborne Diseases in a Conference Room with Thermal Stratification” in the journal Building and Environment. The full paper is available at this link.

The first author of this paper, Jake Castellini, is a Ph.D. student in the SBS Lab, where his research focuses on the application of efficient CFD and well-mixed modeling techniques to the understanding of indoor transmission of airborne pathogens.

Congratulations to Jake on publishing this paper!

(Contours of the room averaged contaminant concentration for the baseline case normalized by the average breath-zone concentration)

Off

Traditional

White

Paper on Investigation of HVAC Operation Strategies for Office Buildings During COVID-19 Pandemic has been published in Building and Environment.

Anonymous — Thu, 09 Dec 2021 21:13:53 +0000

Paper on Investigation of HVAC Operation Strategies for Office Buildings During COVID-19 Pandemic has been published in Building and Environment. Anonymous (not verified) Thu, 12/09/2021 - 14:13

It is crucial for buildings to be resilient to unforeseen challenges, such as providing safe indoor environment during the COVID-19 pandemic, while ensuring sustainability for long-term operation. This paper investigates the effectiveness of various strategies to improve indoor air quality during the COVID-19 pandemic for a prototype office building located in Denver, CO. The detailed system model and newly developed component models allow for analysis of building resiliency and sustainability under a wide range of possible scenarios.

This work has been published under the title " Investigation of HVAC Operation Strategies for Office Buildings During COVID-19 Pandemic " in the journal Building and Environment. The full paper is available at this link.

The first author of this paper, Cary Faulkner, is a Ph.D. student in the SBS lab and his research interests include building system modeling, computational fluid dynamics, indoor environment modeling, and machine learning.

Congratulations to Cary on publishing this paper!

Off

Traditional

White