• Energy Research

Abstract This study analyzed the interconnections between urban structure and socioeconomic, demographic and lifestyle variables and direct ground transport greenhouse gas (GHG) emissions in the Helsinki metropolitan region in Finland by using a latent class choice model (LCCM). The aim of the study was to identify and improve our understanding of the latent modality styles which guide people's everyday travel choices, and the resulting GHG implications. The GHG implications for different modality style groups are particularly interesting, since such analysis has not been included in previous studies. This study used the transport survey of the Helsinki Region Transport (HSL) from 2012, including over 17,000 trips, and consisted of two parts: first, the population was divided into classes based on latent class analysis, and secondly, the mode choices and GHG emissions were modelled for each class. Seven modality style groups were defined with strongly varying GHG impacts and travel profiles. According to the class specific choice modelling the probabilities of selecting different modes also varied significantly. The study offers new information for designing effective mitigation policies for different types of modality style groups. For example, car-oriented groups would benefit from more fuel-efficient vehicles and vehicles with alternative power sources, whereas the multimodal traveler could be more receptive to policies promoting cycling and public transport. Overall, the study depicts the potential of the latent class method to study the emissions caused by heterogeneous populations and to search for efficient GHG mitigation possibilities.

Buildings use 30-40 % of all energy resources and are thus their main consumers in modern society. Moreover, buildings require a vast amount of different raw materials. During the last two decades, several green building certifications have been created in order to consider social, economic and environmental aspects of sustainability of buildings. One of the most famous and widely used of these certifications is Leadership in Energy and Environmental Design (LEED). So far, the use of LEED has concentrated in the US and other developed countries. One reason that restricts the use of this point-based system certification in developing countries is the limited data about its costs. In this study, the extra cost of the certification process will be evaluated besides the changes needed in the design of the building to reach the points required by LEED. At the first stage, the number of points the case study earns in its current format (Scenario 1) were found out, then the cost difference of getting either the Certified (Scenario 2) or Silver (Scenario 3) level LEED certification for the building was studied. It was found that besides some technical considerations, filling the criteria of the Certified and Silver level increases the total costs of construction by 3.4% and 5.9%. Further improvement of the building’s energy efficiency would enable the attainment of a higher-level certification. The results of the study could help to promote the use of green building certifications in Western Asia.

AbstractNumerous studies have illustrated how denser urban forms lead to smaller greenhouse gas (GHG) emissions from passenger transport. Many of these studies have excluded aviation since the association between urban structure and air travel is not as intuitive as it is the case of ground travel. However, several recent studies have concluded that air travel is a significant contributor to the GHGs from passenger transport. Furthermore, even air travel habits depend heavily on lifestyles and socio-economic factors that are related to the urban form. Here we analyse the interactions between urban structure and different transportation modes and their GHG impacts in Finland. The study utilises the data from the Finnish Transportation Agency’s passenger traffic survey from May 2010 to May 2011, which includes over 12000 people and over 35000 trips. The survey is based on one-day travel diaries and also includes additional data on long-distance trips from a longer period. Methodologically, the study takes a traveller’s perspective to assess the GHG emissions from passenger transport. We found that (1) air travel breaks the pattern where GHG emissions decrease with increasing density of urban structures, and (2) in the metropolitan region there is a clear trade-off between car-ownership and air travel in the middle income class. The main policy implication of our study is that air travel must be included in GHG assessments and mitigation strategies targeting travel behaviour. In dense urban regions, the emissions of air travel have the potential to offset the gain from reduced private driving.

Depletion of natural resources and climate change are undoubtedly the biggest challenges that humankind faces today. Here, buildings have a crucial role since they consume the majority, i.e., 30% to 40% of the total energy resources. Green building certification is one of the solutions to limit the energy use in buildings. In addition, it is seen to indicate a consideration for sustainability aspects in construction. LEED is the most widely used certificate worldwide. However, recently some critics have raised doubts about LEED and whether it actually implies sustainability. Most of the criticism has been targeted to the energy aspects of LEED. Nevertheless, there is no consensus on the usefulness of LEED: is it really beneficial for the environment, and is it worth of the money and time invested on the certification process? In this study a critical analysis of the literature to find an answer to this question is presented. Altogether 44 peer reviewed articles dealing with the abovementioned issue were selected out of 164 search result. Based on the studied material, the different aspects of LEED from the viewpoint of energy-efficiency are discussed. From the 44 reviewed articles, ten articles state that LEED certificate indicates energy efficiency while eight papers end up with an opposite conclusion. The rest of the papers do not take any stand on this matter. The study showed that energy efficiency of LEED-certified buildings is questionable especially at lower levels, i.e., certified. Therefore, it is recommended to modify the Energy and Atmosphere category of LEED in order to improve the actual energy performance of buildings.

Abstract Consumption-based carbon footprint (CBCF) assessments have become increasingly important in studying the drivers of climate change from a consumer perspective. A wide range of studies and approaches for CBCF have been presented, yet a systematic and interpretative synopsis of the literature is missing. We present a comprehensive review of more than 100 CBCF studies published in Scopus-indexed journals until 2019. We analyze the methodological and conceptual development of spatially related CBCFs and provide guidance for future research. While the recent emergence of several global multi-region input-output (MRIO) models has meant remarkable development in assessment accuracy, there is space for improvement in hybrid-modeling and increasing sectoral detail. Furthermore, it was recognized that studies published under the same CBCF label actually fall into two categories with different definitions and potentially significantly different outcomes. We suggest labeling these as Areal CF (ACF) and Personal CF (PCF) in the future. ACF encompasses the CBCF of economic activities within selected geographic boundaries, and the global production and delivery chain emissions of the goods and services consumed therein, including those consumed by visitors. PCF covers the consumption of the residents of the area regardless of where the consumption takes place but excludes the consumption of visitors within the area in question. ACF analyses typically include government consumption and investments, whereas PCF analyses normally exclude these. This scope issue is seldom brought up in individual studies, and it currently takes a lot of effort and expertise to classify existing studies, which hinders their usability for policy-making. In addition, we suggest that future studies position themselves among previous studies on the same location, discuss potential reasons for differences in the results, and consider these when drawing policy conclusions.

Avoiding urban sprawl and increasing density are often considered as effective means to mitigate climate change through urban planning. However, there have been rapid technological changes in the fields of housing energy and private driving, and the development is continuing. In this study, we analyze the carbon footprints of the residents living in new housing in different urban forms in Finland. We compare the new housing to existing housing stock. In all areas, the emissions from housing energy were significantly lower in new buildings. However, in the inner urban areas the high level of consumption, mostly due to higher affluence, reverse the gains of energy efficient new housing. The smallest carbon footprints were found in newly built outer and peri-urban areas, also when income level differences were taken into account. Rather than strengthening the juxtaposition of urban and suburban areas, we suggest that it would be smarter to recognize the strengths and weaknesses of both modes of living and develop a more systemic strategy that would result in greater sustainability in both areas. Since such strategy does not exist yet, it should be researched and practically developed. It would be beneficial to focus on area specific mitigation measures.