Yekang Ko

Bio: Yekang Ko is an academic researcher from University of Oregon. The author has contributed to research in topics: Urban planning & Renewable energy. The author has an hindex of 10, co-authored 16 publications receiving 449 citations. Previous affiliations of Yekang Ko include University of California, Berkeley & University of Texas at Arlington.

Socio-technical evolution of Decentralized Energy Systems: A critical review and implications for urban planning and policy

Abstract: The growth of Decentralized Energy Systems (DES) signals a new frontier in urban energy planning and design of local energy systems. As affordability of renewable energy technologies (RET) increases, cities and urban regions become the venues, not only for energy consumption but also for generation and distribution, which calls for systemic and paradigmatic change in local energy infrastructure. The decentralizing transitions of urban energy systems, particularly solar photovoltaic and thermal technologies, require a comprehensive assessment of their sociotechnical co-evolution – how technologies and social responses evolve together and how their co-evolution affects urban planning and energy policies. So far, urban planning literature has mainly focused on the impact of physical urban forms on efficiency of energy consumption, overlooking how the dynamics of new energy technologies and associated social responses affect local systems of energy infrastructure, the built environments and their residents. This paper provides an interdisciplinary review on the co-evolving technical and social dynamics of DES focusing on Distributed Generation (DG), MicroGrids (MG), and Smart MicroGrids (SMG), in order to draw insights for their integration in urban planning and policy, in particular reference to climate change mitigation and adaptation planning.

Urban Form and Residential Energy Use A Review of Design Principles and Research Findings

Abstract: The effect of urban form on residential energy use has attracted much research, but it may be difficult to grasp the conclusions of that research because of inconsistencies in scope and methods employed. This article reviews the literature on how urban form affects residential energy use, particularly energy for space-conditioning (heating and cooling). Climate-responsive design principles are examined first and linked to research on how several factors affect residential energy use: housing type, density (physical compactness and dwelling unit density), community layout (street orientation and building configuration), and planting and other surface coverage. The research on each of these factors is summarized under three categories: experiments, simulation modeling, and statistical analysis of empirical data. Finally, implications for future research are discussed and suggestions for planning are made.

The effect of urban form and residential cooling energy use in Sacramento, California

Abstract: The impact of urban form on residential space-conditioning energy use has been controversial in recent planning literature. This study empirically evaluates the association between urban form and residential energy use, focusing particularly on residential electricity use for space cooling in the City of Sacramento, California. We characterize urban form, property conditions, and demographic and socioeconomic characteristics by applying spatial metrics embedded within a geographic information system where LiDAR data effectively include each building and the surrounding vegetation. A statistical model is applied to assess the relationship between these explanatory variables and the estimated summer air-conditioning energy use. Controlling for other variables, higher population density, east�west street orientation, higher green space density, larger vegetation on the east, south, and especially the west sides of houses, appears to have statistically significant effects on reducing summer cooling energy use. This study quantifies the built environment impact on the energy demand of air conditioning and informs planners as they craft urban planning and design policies for energy conservation.

A blockchain-based smart grid: towards sustainable local energy markets

Abstract: The increasing amount of renewable energy sources in the energy system calls for new market approaches to price and distribute the volatile and decentralized generation. Local energy markets, on which consumers and prosumers can trade locally produced renewable generation directly within their community, balance generation and consumption locally in a decentralized approach. We present a comprehensive concept, market design and simulation of a local energy market between 100 residential households. Our approach is based on a distributed information and communication technology, i.e. a private blockchain, which underlines the decentralized nature of local energy markets. Thus, we provide energy prosumers and consumers with a decentralized market platform for trading local energy generation without the need of a central intermediary. Furthermore, we present a preliminary economic evaluation of the market mechanism and a research agenda for the technological evaluation of blockchain technology as the local energy market’s main information and communication technology.

City-integrated renewable energy for urban sustainability

Abstract: To prepare for an urban influx of 2.5 billion people by 2050, it is critical to create cities that are low-carbon, resilient, and livable. Cities not only contribute to global climate change by emitting the majority of anthropogenic greenhouse gases but also are particularly vulnerable to the effects of climate change and extreme weather. We explore options for establishing sustainable energy systems by reducing energy consumption, particularly in the buildings and transportation sectors, and providing robust, decentralized, and renewable energy sources. Through technical advancements in power density, city-integrated renewable energy will be better suited to satisfy the high-energy demands of growing urban areas. Several economic, technical, behavioral, and political challenges need to be overcome for innovation to improve urban sustainability.