A comparison of greenhouse gas emissions in the residential sector of major Canadian cities

One of the most significant sources of greenhouse gas (GHG) emissions in Canada is the buildings sector, with over 30% of national energy end-use occurring in buildings. Energy use must be addressed to reduce emissions from the buildings sector, as nearly 70% of all Canada’s energy used in the residential sector comes from fossil sources. An analysis of GHG emissions from the existing residential building stock for the year 2010 has been conducted for six Canadian cities with different climates and development histories: Vancouver, Edmonton, Winnipeg, Toronto, Montreal, and Halifax. Variation across these cities is seen in their 2010 GHG emissions, due to climate, characteristics of the building stock, and energy conversion technologies, with Halifax having the highest per capita emissions at 5.55 tCO2e/capita and Montreal having the lowest at 0.32 tCO2e/capita. The importance of the provincial electricity grid’s carbon intensity is emphasized, along with era of construction, occupancy, floor area, and climate. Approaches to achieving deep emissions reductions include innovative retrofit financing and city level residential energy conservation by-laws; each region should seek location-appropriate measures to reduce energy demand within its residential housing stock, as well as associated GHG emissions

Reducing GHGs from UK Households ‐ An Examination of Local Authority‐Level Data

As the threat of irreversible climate change has increased over time, the UK has focused on reducing its carbon emission levels. International treaties such as the Kyoto Protocol have informed national targets, directing the UK in reducing its climate impact. In order to achieve this an understanding of the factors that affect carbon emission reductions is vital. Identifying what dictates the success of UK local authorities in reducing their carbon emissions addresses this problem. The research uses secondary data regarding local authorities’ carbon emissions and regression analyses to explore the key factors affecting domestic emission levels over time. The research goes into further detail than existing literature through exploring sources of emissions across different sectors and analysing emissions reductions specifically between 2005-2016. Substantial and relatively consistent domestic emissions reductions were achieved in this time frame, exceeding the reductions provided by decarbonisation of the electricity grid. Standard deviations of 3% were observed in this sector, compared with 12% from Industrial & Commercial emissions. While population density demonstrated a statistically significant correlation with domestic GHG reductions, gross disposable household income was not found to be significant; however, it is a relevant indicator of total emissions levels in 2016. Through identifying these factors, suggestions to local government are made such as the implementation of region-specific strategies, tailoring these to the exact characteristics of a local authority. Furthermore, consideration of population density in conjunction with domestic and urban planning will allow for future emissions reductions to occur across the UK

Thermal Performance of Vacuum Insulated Window Shutter Systems

Windows are a major area of heat loss in buildings losing up to 10 times more energy compared to other building elements. Thermal shutters are used to improve the energy performance of windows in both hot and cold climatic conditions. The performance of thermal shutters however greatly depends on the thermal insulation and construction detailing, specifically cold-bridging, through the shutter, as well as between the shutter and window frames. This study evaluates the effects of cold-bridging, trickle ventilation and the size of the air cavity, between the vacuum insulated shutter and the window, on the performance of window thermal shutters. Thermal simulations are conducted in VOLTRA (Thermal analysis software) to assess the conditions. The results indicate that although thermal shutters reduce heat-loss through windows, their performance could be significantly affected by cold-bridging by up to 90%. The additional thermal resistance due to the air cavity and the ventilation through the trickle vent appeared to be much less significant compared to the effects of thermal bridging

Participation in domestic energy retrofit programmes: key spatio-temporal drivers

The Canadian government created the EcoENEGY Retrofit for Homes programme (2007–12) to improve residential energy efficiency and reduce emissions produced through energy use. The uptake of retrofits varied both spatially and temporally. This research examines spatio-temporal patterns of retrofit adoption to understand the drivers behind participation in the grant programme and assess how future grant-based programmes might improve the uptake of efficiency measures. Temporal analysis demonstrated continued growth of programme participation over its original period of availability, and this accelerated once the programme was extended for an additional year after its original closure date. However, some spatial correlations weakened, which may be attributable to changes in programme design during the extension period. Seasonal variation was also observed, with spikes in retrofit activity occurring in winter. A regression analysis for conversion rates in Ontario and British Columbia displayed significant positive correlations for high shelter costs (>30% of household income) and households occupied by usual residents (regular occupants). Population density, median property value (only in Ontario) and units that were recently occupied demonstrated negative correlations. Spatial variation at both the city and neighbourhood levels suggests a greater degree of programme customisation is required to ensure uniform building stock improvement

Turning national retrofit policies into local action: examples from the US BBNP and the Canadian eco-energy programs

Improving energy efficiency in existing dwellings is critical in efforts to address climate change. National level retrofit policies are useful for delivering large volumes of funding with a coordinated program brand. However, for countries such as the US and Canada, energy issues vary considerably nationwide and are therefore governed at the state or provincial level. Finding ways to calibrate national level policy objectives and structures for effective delivery at the local level is a critical policy priority, but is poorly understood by policymakers and underrepresented in academic research. This paper addresses this gap by analysing the US Better Buildings Neighborhood Program (2010-2013), and the Canadian Eco-Energy Retrofit Program (2009-2013). Both of these programs were created with a national level overarching structure and objectives, but were implemented in different ways at the state/provincial and local levels. The impact evaluations of each program found that they were broadly successful at the national level. This paper considers how each program targeted local action along three themes. 1) Housing stock factors including population, social, and demographic issues inherent to the spatial distribution and fundamentally unchangeable. 2) Program design factors consider issues such as leveraging local funding and resource pools. 3) Program delivery factors include implementation strategies for driving demand and workforce engagement. The results suggest that demographic factors are not predictive of overall program success (measured as total upgrades and/or energy savings). Effective program design and implementation can compensate for housing stock factors. A set of best practice principles are described for adapting national level program structures for effective local program delivery

Scenarios of technology adoption towards low-carbon cities

Technological change has often been presented as a readily accepted means by which long-term greenhouse gas (GHG) emission reductions can be achieved. Cities are the future centers of economic growth, with the global population becoming predominantly urban; hence, increases or reductions of GHG emissions are tied to their energy strategies. This research examines the likelihood of a developed world city (the Greater Toronto Area) achieving an 80% reduction in GHG emissions through policy-enabled technological change. Emissions are examined from 3 major sources: light duty passenger vehicles, residential buildings and commercial/institutional buildings. Logistic diffusion curves are applied for the adoption of alternative vehicle technologies, building retrofits and high performance new building construction. This research devises high, low and business-as-usual estimates of future technological adoption and finds that even aggressive scenarios are not sufficient to achieve an 80% reduction in GHG emissions by 2050. This further highlights the challenges faced in maintaining a relatively stable climate. Urban policy makers must consider that the longer the lag before this transition occurs, the greater the share of GHG emissions mitigation that must addressed through behavioural change in order to meet the 2050 target, which likely poses greater political challenges

Syntheses of heterocyclic derivatives as potential cytotoxic compounds evaluated toward hepatocellular and cervical carcinoma cell lines

ABSTRACT. Through the present work the 3-oxo-N,3-diphenylpropamide derivatives 5a,b were used to synthesize pridine, pyrazole and thiophene derivatives. 3-Phenylisoxazol-5(4H)-one produced from the reaction of ethyl benzoylacetate was used as the key starting compound for different multi-component reactions. The synthesized compounds were evaluated toward Hepatocellular carcinoma HepG2 and cervical carcinoma HeLa cell lines. Compounds 3b, 5b, 7b, 7d, 9c, 9d, 15e, 15f, 16b, 18b, 18e, 18f, 19e and 19f were the most cytotoxic compounds against the tested cell lines. The results obtained in this work encourage further work in the future to produce new cytotoxic compounds.   KEY WORDS: Diphenylpropamide, 3-Phenylisoxazole, Pyran, Pyridine, Cytotoxicity Bull. Chem. Soc. Ethiop. 2023, 37(1), 141-158.                                                              DOI:https://dx.doi.org/10.4314/bcse.v37i1.1

Uses of chalcone acetophenone to synthesis heterocyclic compounds with cytotoxic and c-Met kinase activities

ABSTRACT. The aim of present study was the uses of a series of α,β-unsaturated carbonyl compounds (chalcones), in the synthesis of pyridine, pyran, thiophene, thiazole, together with their uses in heterocyclic synthesis. The work has resulted in the synthesis of a variety of 2,5-dihydropyridine, hydrazide-hydrazone, thiophene derivatives, coumarin, pyran and thiazolo[4,5-d]thiazole derivatives. The antitumor activities of the newly synthesized products were carried out against three cancer cell lines namely MCF-7, NCI-H460 and SF-268 and normal human cell line WI38.  In addition, the inhibitions of most of the synthesized compounds against             c-Met kinase were studied and results showed that many compounds were of high inhibitions, and these are considered as promising anticancer agents. The results obtained encouraged further work in the future.    KEY WORDS: Chalcones, Heterocyclic, Pyridine, Pyran, Thiophene, Thiazole, Antitumor Bull. Chem. Soc. Ethiop. 2022, 36(1), 149-172.                                                             DOI: https://dx.doi.org/10.4314/bcse.v36i1.13                                                      &nbsp

Analysis of greenhouse gas mitigation performance in UK urban areas

As the threat of irreversible climate change has increased over time, the UK has continued to set increasingly ambitious policies to reduce its carbon emission. An assessment of mitigation progress to date at the local authority level clarifies the factors that have affected greenhouse gas (GHG) emissions on the path to carbon neutrality. This research uses regression analyses between local authorities’ GHG emission redcutions and selected explanatory variables (including population density, household income, and manufacturing employment) identified from the literature to explore mitigation performance over time, focusing on GHG emissions changes between 2005 and 2016. Substantial and relatively consistent GHG emissions reductions were achieved in this time frame, with average total reductions across UK local authorities of 31.2%. Population density was moderately-to-strongly correlated with the success of transportation GHG emissions mitigation, though this sector has seen the smallest percentage declines over this period. Local authorities with densities below 25 inhabitants per hectare were generally among the poorest performers in transportation GHG mitigation. This underscores the need to support remote working and electrification of personal transportation in areas where public/active transportation options are not viable alternatives. Furthermore, consideration of population density in conjunction with domestic and urban planning will allow for future emissions reductions to occur across the UK. Fundamentally, GHG emissions reductions to date are largely driven by historic factors (density), shifting economic structures (deindustrialisation), and centralised initiatives (decarbonisation of electricity generation)