• Energy Research

The subject addressed in this article is the application of the life cycle assessment (LCA) method for studying the greenhouse gas emissions attributable to public bus transport. The article provides a discussion on the results of the authors’ in-house study on the greenhouse gas (GHG) emissions generated over the life cycle of the buses used in Poland’s public transport with the use of well-to-wheel (WTW) fuel life cycle analysis. The project started by adopting the methodology and assumptions for the research; next, the data required to perform the relevant analyses were collected and the greenhouse gas emissions attributable to the operation of buses equipped with both diesel fuel (DF) internal combustion engines and electric engines (BEVs) were assessed against real-life data using a selected Polish municipal transport company as an example in 2022. The study also included an assessment of GHG emissions from electric buses powered by renewable energy sources (RESs), using data from the chosen municipal transport company. For the RES fractions of 25%, 50%, and 75% in the energy mix, emission reductions of approx. 19%, 38%, and 57% have been achieved, respectively. For an energy mix entirely derived from RESs, the reduction in emissions comes to ca. 76% vis-à-vis Poland’s energy mix in 2022.

With the decline in price of the photovoltaic’s (PVs) and the increase in greenhouse gases due to the use of fossil fuels the use of photovoltaic as a power source for water pumping is becoming the more attractive solution instead of using diesel/gasoline generators. This paper deal with the optimal sizing of the water pumping system instead of gasoline generator for the irrigation of the onion farms in Cameroon it also discusses a share of greenhouse gas emitted from the cultivation of onions. The study uses the data generated from a survey carried out between 2014 and 2015 of consumption gasoline/lubrificant and water production from generators on the duration of the culture in the main production Area ''10°35’N, 14°18’E''. The results of the analysis indicates that the Life Cycle Cost, 'LCC' of the photovoltaic water pumping system depends on its capital costs (67 % of LCC) while the LCC of gasoline pumping system depends largely on recurring costs (79 % of LCC). The CO2 emissions depend not only on the type of land but on the stage of plant growth. This research work also demonstrates that using the PV water pumping system can improve living conditions of farmers.

Abstract The healthcare sector is responsible for around 4.4 % of worldwide greenhouse gas emissions, according to estimates. Operating rooms are responsible for the greatest rate of resource consumption and overall hospital waste, varying from 20 % to 33 %. Hence, it is essential to fully discover the environmental impact of surgical procedures to obtain insight into the total emissions associated with the healthcare sector. Moreover, the lack of uniformity in data collection and the discrepancy of the data used by researchers makes it challenging, if not ineffective, to conduct a rigorous scientific comparison among the currently available studies on the environmental impacts of surgical procedures. This study aims to provide a practical and standardised framework that can be utilised to evaluate, simply and consistently, the environmental impacts of surgical procedures. To achieve this goal, a comprehensive literature review was conducted to assess the state of the art in environmental impact analyses related to surgical practices. This review highlighted significant variability and heterogeneity in existing methodologies, serving as the foundation for developing a more consistent approach. By simulating three different scenarios based on data availability, a methodology is proposed to conduct an environmental impact analysis tailored to the specific needs of researchers. Adopting a uniform methodology guarantees the inclusion of important variables and factors, preventing any oversights in the evaluation of the entire process.

To reduce greenhouse gas emissions from passenger vehicles, new energy vehicles are actively promoted by China’s government. Various power system types are being developed and their sales keep increasing. However, there is uncertainty about the greenhouse gas emission of different vehicle types. This paper studies the life cycle carbon emissions of passenger vehicles in China. A calculation model is established with consideration of all types of power systems, model classes, and electric driving ranges. In order to calculate and compare the effect of carbon emission reduction on all types of vehicles, a sensitivity analysis is conducted in two ways to study three of the main influencing factors. The results show the carbon emission-reducing effect of different factors on different stages in the life cycle. It is known that different influencing factors have different effects on these stages. Since there is a variation in different vehicle types, the carbon reduction effect caused by these factors is different for these vehicle types. This paper describes a sensitivity analysis of three main influencing factors and puts forward relevant policy recommendations to reduce the carbon emissions of passenger cars during their life cycle based on these results. It is necessary to take the vehicle life cycle as a whole for carbon emission management. The conclusions of this paper can be used for vehicle manufacturers to decide the focus of technology research, and also have important reference significance for enterprises when making life cycle carbon reduction strategies for their products. It is also of certain value for China to formulate a medium- and long-term carbon emission reduction strategy for the passenger car industry.

In recent years, waste incineration power generation has become one method for domestic waste treatment. The carbon footprint can provide a quantitative tool for evaluating greenhouse gas emissions from this process. A typical solid waste incineration plant in Jiangxi Province was chosen as the research object to calculate the carbon footprint and analyze the main stages of the life cycle of waste incineration power generation, aiming to reduce greenhouse gas emissions in such plants. The life cycle assessment (LCA) method was adopted, and the life cycle boundary of the power products generated by waste incineration was defined using 1 kW·h of grid power as the functional unit. The results showed that the carbon footprint per unit of grid power generation was 0.841 kg CO_2e/(kW·h), and the carbon footprint of per unit waste was 342.39 kg CO_2e/t. This relatively low carbon footprint might be attributed to the low calorific value of the selected garbage. The waste incineration stage had the highest emissions, accounting for 78% of the total. Therefore, efforts to reduce greenhouse gas emissions from waste incineration should primarily focus on minimizing direct carbon emissions from waste combustion. Operating the incineration plant at its rated load as much as possible is crucial to achieve this goal, along with increasing the recycling rate of plastic components and transitioning from diesel vehicles to electric vehicles.

Abstract The food supply chain is currently challenged by the imperative to sustainably feed the increasingly expanding population while simultaneously striving to meet global net-zero emission targets. The dairy sector is widely considered as a carbon-intensive industry, contributing to significant greenhouse gas (GHG) emissions thereby exacerbating global warming. Here, we first summarize recent studies on determining GHG emissions of various dairy products, which suggests that farms are the primary emission hotspots in the dairy supply chain. Next, the vital role of novel techniques and emerging strategies to reduce carbon emissions in the dairy industry is emphasized at both local- and systematic levels. The implementation of targeted techniques at each stage, along with policy initiatives such as carbon pricing, plant-based alternatives, international standards and clean air act, play a vital role in establishing global optimization to mitigate climate warming. Despite these progresses, standards and guidelines of emission reduction for the dairy industry are currently lacking, which calls for continuous efforts to fill the gap. Graphical Abstract

Oilcane — an oil-accumulating crop engineered from sugarcane — and microbial oil have the potential to improve renewable oil production and help meet the expected demand for bio-derived oleochemicals and fuels. To assess the potential synergies of processing both plant and microbial oils, the economic and environmental implications of integrating microbial oil production at oilcane and traditional sugarcane biorefineries were characterized. Due to decreased crop yields that lead to higher simulated feedstock prices and lower biorefinery capacities, current oilcane prototypes result in higher costs and carbon intensities than microbial oil from sugarcane. To inform oilcane feedstock development, the required biomass yields (as a function of oil content) for oilcane to achieve financial parity with sugarcane were calculated. At 10 dwt % oil, oilcane can sustain up to 29% less yield than sugarcane and still be more profitable in 95% of simulated scenarios. With microbial oil production from cane juice, achieving this target results in a minimum biodiesel selling price of 2.14 [1.58, 2.76] USD∙L-1 (presented as median [5th, 95th] percentiles), a carbon intensity of 0.519 [0.475, 0.565] kg·CO2e·L–1, and a total biodiesel yield of 2060 [1770, 2350] L·ha–1·y–1.

Agriculture is under pressure to reduce its environmental impact. The use of renewable energy sources has potential to decrease these impacts. Maize is one of the most significant crops in South Africa and approximately 241,000 hectares are irrigated. This irrigation is most commonly powered by grid electricity generated using coal. However, South Africa has high solar irradiation, which could be used to generate photovoltaic electricity. The aim of this study was to determine the environmental mitigation potential of replacing grid-powered irrigation in South African maize production with photovoltaic irrigation systems using Life Cycle Assessment. The study included the value chain of maize production from cultivation to storage. Replacing grid electricity with photovoltaic-generated electricity leads to a 34% reduction in the global warming potential of maize produced under irrigation, and—applied at a national level—could potentially reduce South Africa’s greenhouse gas emissions by 536,000 t CO2-eq. per year. Non-renewable energy demand, freshwater eutrophication, acidification, and particulate matter emissions are also significantly lowered. Replacing grid electricity with renewable energy in irrigation has been shown to be an effective means of reducing the environmental impacts associated with South African maize production.