Effects of urban functional fragmentation on nitrogen dioxide (NO2) variation with anthropogenic-emission restriction in China

Urban functional fragmentation plays an important role in assessing Nitrogen Dioxide (NO2) emissions and variations. While the mediated impact of anthropogenic-emission restriction has not been comprehensively discussed, the lockdown response to the novel coronavirus disease 2019 (COVID-19) provides an unprecedented opportunity to meet this goal. This study proposes a new idea to explore the effects of urban functional fragmentation on NO2 variation with anthropogenic-emission restriction in China. First, NO2 variations are quantified by an Autoregressive Integrated Moving Average with external variables-Dynamic Time Warping (SARIMAX-DTW)-based model. Then, urban functional fragmentation indices including industrial/public Edge Density (ED) and Landscape Shape Index (LSI), urban functional Aggregation Index (AI) and Number of Patches (NP) are developed. Finally, the mediated impacts of anthropogenic-emission restriction are assessed by evaluating the fragmentation-NO2 variation association before and during the lockdown during COVID-19. The findings reveal negative effects of industrial ED, public LSI, urban functional AI and NP and positive effects of public ED and industrial LSI on NO2 variation based on the restricted anthropogenic emissions. By comparing the association analysis before and during lockdown, the mediated impact of anthropogenic-emission restriction is revealed to partially increase the effect of industrial ED, industrial LSI, public LSI, urban functional AI and NP and decrease the effect of public ED on NO2 variation. This study provides scientific findings for redesigning the urban environment in related to the urban functional configuration to mitigating the air pollution, ultimately developing sustainable societies.

Climate Change Mitigation Policies in the Transportation Sector in Rio de Janeiro, Brazil

This study analyzes climate change mitigation policies focused on light-duty electric vehicles (LDEVs) in the transportation sector in Rio de Janeiro state, Brazil, in the 2016–2050 period. We use the Open Source Energy Modeling System (OSeMOSYS) to analyze scenarios that consider greater uptake of LDEVs in different time frames, implementation of a CO2 emission restriction policy, exclusion of fossil fuels from the power mix, and a combination of these policies. We find that carbon pricing, along with higher rates of LDEVs adoption, causes the highest emission reductions (up to 47%), albeit at higher costs. LDEVs become the preferred vehicle technology as soon as they reach cost parity with internal combustion engine vehicles in different scenarios. Greater LDEVs uptake, however, leads to increased electricity consumption (up to 3%), which is provided by fossil fuels when there is no emission restriction policy. If restrictions are placed on the expansion of fossil fuel power plants, fewer LDEVs are adopted (up to less than 26%) because there is not enough electricity to supply the demand. Given the state’s power mix in 2016 (58% provided by fossil fuels), investment in zero-carbon energy is necessary for mitigation policies in the transportation sector to be effective.

Renewable Energy Investment under Carbon Emission Regulations

This paper considers a risk-neutral energy supplier who operates an electricity plant in an uncertain demand market. To characterize the impact of carbon emission quota and emergency supply cost of coal electricity, we first consider four different cases, (1) traditional energy without carbon emission restriction; (2) traditional energy with carbon emission quota; (3) mixed energy (both traditional and renewable energy) without carbon emission restriction, and (4) mixed energy with carbon emission quota, to find the optimal renewable energy investment level and coal inventory mechanism for an energy supplier. Then, through the analysis we derive the resulting equilibriums: coal inventory for electricity generation and the investment of renewable energy capacity. By comparing the performances under different scenarios, we find that (a) renewable energy establishment can mitigate the depression of carbon emission constraint, (b) the energy supplier can obtain positive benefits from optimal mixed energy strategy if the additional emergency cost of traditional energy is not too high, and (c) the optimal renewable energy capacity level is decreasing in the carbon emission quota. Our numerical simulations imply that the impact of additional emergency cost to the profit difference between mixed energy strategy and traditional energy strategy is mediated by carbon emission quota.

Increasing the energy efficiency of dwelling houses: case study of residential quarter in Upper Silesia, Poland

The paper assesses thermomodernisation measures aimed at improving energy efficiency of dwelling houses in a city quarter in Upper Silesia, Poland. The area was encompassed by the city council’s program of emission restriction that promoted energy saving activities. The assessment was carried out by means of thermographic examination. It confirmed the fact that the thermomodernisation measures taken so far provided considerable improvement, but did not solved all issues. Further works should be undertaken on the basis of thorough examination of the current condition of the buildings.