A Demand-Centered, Hybrid Life-Cycle Methodology for City-Scale Greenhouse Gas Inventories

Department of Civil Engineering, University of Colorado Denver, Denver, Colorado, USA.
Environmental Science and Technology (Impact Factor: 5.33). 10/2008; 42(17):6455-61. DOI: 10.1021/es702992q
Source: PubMed


Greenhouse gas (GHG) accounting for individual cities is confounded by spatial scale and boundary effects that impact the allocation of regional material and energy flows. This paper develops a demand-centered, hybrid life-cycle-based methodology for conducting city-scale GHG inventories that incorporates (1) spatial allocation of surface and airline travel across colocated cities in larger metropolitan regions, and, (2) life-cycle assessment (LCA) to quantify the embodied energy of key urban materials--food, water, fuel, and concrete. The hybrid methodology enables cities to separately report the GHG impact associated with direct end-use of energy by cities (consistent with EPA and IPCC methods), as well as the impact of extra-boundary activities such as air travel and production of key urban materials (consistent with Scope 3 protocols recommended by the World Resources Institute). Application of this hybrid methodology to Denver, Colorado, yielded a more holistic GHG inventory that approaches a GHG footprint computation, with consistency of inclusions across spatial scale as well as convergence of city-scale per capita GHG emissions (approximately 25 mt CO2e/person/year) with state and national data. The method is shown to have significant policy impacts, and also demonstrates the utility of benchmarks in understanding energy use in various city sectors.

23 Reads
    • "These programs can be concreted through two types of measures: firstly, through corrective measures based on existing and working cities and secondly, through preventive measures based on urban planning master plans. Corrective measures have been analyzed in many works addressing GHG emissions or with carbon footprint calculations through consumption-based or input-output approaches (Dhakal, 2009; Jones and Kammen, 2011; Lin et al., 2013; Minx et al., 2013; Petsch et al., 2011; Puliafito and Allende, 2007; Ramaswami et al., 2008; Sovacool and Brown, 2010; Weber and Matthews, 2008). These works include GHG emissions from all individual daily activities, including variables hardly considered by urban planning decisions (daily journeys, drinking water, gas or electricity consumption as well as wastewater and waste management). "
    [Show abstract] [Hide abstract]
    ABSTRACT: tThe growing concerns of climate change require implementing measures to quantify, to monitor and tominimize greenhouse gas (GHG) emissions. Nonetheless, most of the measures available are not easy todefine or execute because they rely on current emissions and have a corrective character. To address thisissue, a methodology to characterize GHG emissions that allows implementing preventive measures isproposed in this paper. The methodology is related to household urban planning procedures and con-siders urban infrastructures to characterize GHG emissions and to execute preventive measures basedon sustainability design criteria. The methodology has been tested by applying it to a set of medium-sized municipalities with average GHG emissions from 6,822.32 kgCO2eq/year to 5,913.79 kgCO2eq/yearfor every residential unit. The results indicate that the greatest pollutant source is transport, especially inthe issuance of street network design, followed by gas and electricity consumption. The average undevel-opable land area required for the complete GHG emissions capture amounts to 3.42 m2 of undevelopableland for every m2of urbanizable land and 9.02 m2of undevelopable land for every m2 of built land.
    Land Use Policy 11/2015; 48:223-235. DOI:10.1016/j.landusepol.2015.06.005 · 3.13 Impact Factor
  • Source
    • "Based on the functionality of cities, indirect energy use and associated GHG emissions were computed for the critical urban imported materials mainly including water, fuel, food, and cement (Ramaswami et al., 2008). For Xiamen City, only the materials which produced outside the city area are calculated, so they have no significant overlap with carbon emissions by urban end-use sectors (Section 2.1). "
    • "As a result of globalization, the extraction of resources, production of materials, manufacturing of industrial goods, consumption of products, and disposal of waste are increasingly taking place in different corners of the world. Long and complex global supply chains eventually terminate in cities, which can thus be regarded as the demand and consumption centers of the global economy (Ramaswami et al. 2008; Tukker et al. 2009). According to several authors, traditional, geographically-restricted methods of eco-efficiency evaluation cannot therefore produce sufficient information for the effective management of environmental sustainability in urban environments as they fail to take into account the global traceability of emissions, and past studies have proposed the need for a new consumption-based analysis of urban areas (Turner and Baynes 2010; Wiedmann et al. 2011; Heinonen 2012). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Where urban planning is used to promote environmental sustainability, it has traditionally focused on reducing emissions from housing and traffic. However, cities are increasingly being recognized as consumption centers of the global economy, as the origin of demand, and as the point of termination for complex economic supply chains. Based on results produced by a hybrid life-cycle assessment model, which attributed the end-to-end emissions of supply chains to end users, consumption that is not related to housing or ground transportation was found to account for 30% of regional greenhouse gas emissions on average. In highly urbanized areas, the figure was even higher, at 45%. Furthermore, a literature review indicated that most environmental assessment tools for local city-level and subcity-level urban planning are neither able to identify the environmental impacts of personal consumption nor the relationships between urban structures and personal consumption. Thus, this study concludes that there is an apparent gap between the needs and the means of the regional environmental management of urban areas. (C) 2014 American Society of Civil Engineers.
    Journal of Urban Planning and Development 03/2015; 141(1):04014011. DOI:10.1061/(ASCE)UP.1943-5444.0000196 · 0.81 Impact Factor
Show more


23 Reads
Available from