In order to fulfill the commitment of China to achieve carbon peak by 2030 and carbon neutrality by 2060, all industries have been taking their respective carbon reduction actions. The transportation industry accounts for 11% of CO2 emission of the whole society, and its energy conservation and carbon reduction benefit is of great significance to the national carbon reduction process. New energy vehicles are undoubtedly one of the most important means of carbon emission reduction in the transportation sector. However, electric vehicles still have CO2 emissions, as the fossil fuel use comes from upstream power. To systematically and comprehensively evaluate the CO2 emissions of HEV, PHEV and BEV in the whole process, this study introduces the life-cycle method to research on the past and current situations, and predict future scenarios for ICEV and EV light-duty vehicles at the national and regional levels, by deeply analyzing the generation mix and generating efficiency from the WTT st... [more]

There is a development trend for fuel vehicles to adopt low-carbon emission engines. The sales of cars with low-carbon three-cylinder engines in the Chinese market have declined. Is the life cycle of automotive products with three-cylinder engines entering a recession stage? In order to achieve this research objective, which is to investigate whether assembling a three-cylinder engine affects the life cycle of an automotive product, this paper constructs an ecological theory-based approach to measuring the life cycle of automotive products. First, the logistic model is used to measure the intrinsic growth rate, internal inhibition coefficient, and theoretical upper limit of product sales scale before and after the automotive products are equipped with three-cylinder engines. In the second stage, the Lotka−Volterra model is used to calculate the intrinsic growth rate, internal inhibition coefficient, theoretical upper limit, and symbiosis coefficient of the sales scale of the products b... [more]

Carbon Capture Utilization and Storage (CCUS) is a set of technologies aimed at capturing carbon dioxide (CO2) emissions from point-source emitters to either store permanently or use as a feedstock to produce chemicals and fuels. In this paper, the potential benefits of CCUS integration into the energy supply sector are evaluated from a Life Cycle Assessment (LCA) perspective by comparing two different routes for the CO2 captured from a natural gas combined cycle (NGCC). Both the complete storage of the captured CO2 and its partial utilization to produce dimethyl ether are investigated. Moreover, the assessment is performed considering the region-specific features of two of the largest CO2 emitters in Europe, namely Italy and Poland. Results shows that the complete storage of the captured CO2 reduces Global Warming Potential (GWP) by ~89% in Italy and ~97%, in Poland. On the other hand, the partial utilization of CO2 to produce dimethyl ether leads to a decrease of ~58% in Italy and ~6... [more]

The encouraging Design for Disassembly appears in the literature more and more often. Such a design appears to offer clear environmental advantages. However, there are still not enough research results to support the existence of these benefits. The authors using the Life Cycle Assessment method, which assesses the energy consumption and greenhouse gas emissions during the demolition and operation of steel structure. Steel is completely recyclable and, in terms of tonnage, is the most recycled material worldwide. We assessed three scenarios: (1) complete re-remelting (recycling) of the structure; (2) partial reuse of construction elements + remelting (recovery + recycling); and (3) complete reuse of the structure (recovery). GaBi software was used for the analysis. It was found that the environmental impact varied significantly among the examined scenarios. The first scenario poses the greatest environmental burden. However, compared to Scenario no. 1, Scenario 3’s environmental impact... [more]

New York State’s (NYS) Climate Leadership and Community Protection Act (CLCPA) requires that 100% of the state’s electricity supply be greenhouse gas emissions-free by 2040 and that 6000 megawatts (MW) of solar energy must be installed in NYS by 2025. This study aims to evaluate the environmental impact of electricity generation from New York State distributed solar photovoltaic systems. This cradle-to-grave life cycle assessment (LCA) follows the International Standardization Organization (ISO) framework for LCA, including the goal and scope definition, inventory analysis, impact assessment, and interpretation. The study is based on operational data from 120 existing solar installations. Global Warming Potential varies substantially by site, with the minimum and maximum impact values varying from 25.2 to 88.5 gCO2eq/kWh, and with a mean of 45.6 gCO2eq/kWh. Regression analysis shows this range is attributable to differences in site location, capacity factor, and system design (i.e., mo... [more]

Passenger vehicles are responsible for significant greenhouse gas (GHG) emissions, which calls for accurate and up-to-date estimates of the comparative emissions of the main types of alternative power trains, to enable evidence-based policy recommendations. This paper provides a systematic review and harmonization of the recent scientific literature on this topic. The results show that battery electric vehicles (BEVs) represent the most promising option to decarbonize the passenger vehicle fleet in all considered world regions, with up to −70% reductions in GHG emissions possible, vs. conventional internal combustion engine vehicles (ICEVs) running on petrol. Hybrid electric vehicles (HEVs and PHEVs) are less effective strategies, but they may be useful in bridging the gap between ICEVs and BEVs, especially in those markets that are harder to electrify quickly. Finally, fuel cell vehicles (FCEVs) may also be a viable option, but only if the hydrogen fuel is produced via water electroly... [more]

The study (a) assesses the life cycle energy consumption and air emissions impacts of battery electric buses (e-buses) and conventional buses operated in Vietnam, and (b) compares them with those of hydrogen buses. The results indicate that e-buses and hydrogen buses are preferred options compared to conventional buses in terms of energy consumption, GHG emissions and other air quality impacts over their whole life cycle. Life cycle energy consumption of diesel buses is triple that of e-buses, and is significantly higher than that of hydrogen buses. Replacing conventional buses with e-buses can reduce energy consumption by 50%. For GHG emissions and air quality impacts, the adoption of electric and hydrogen mobility in replacement of conventional buses will reduce GHG emissions by 39%, and other impacts related to air quality by 13% to 90%.

Among the different alternatives for the production of biofuels, food waste could be a favorable bioenergy source. Using food waste as a feedstock has the potential to meet the expectations of the second generation of biofuels, in terms of environmental savings and revenue-generation, and which, along with other valuable co-products, can contribute to biorefinery profits. This study aimed to investigate the early stages of life-cycle assessment (LCA) for restaurant food waste processed into bioethanol, biomethane, and oil, split over different scenarios. Based on a life cycle inventory analysis, the environmental impacts were assessed using an IMPACT 2002+ methodology. The characterized impacts were then normalized against the average impacts, and the normalized results were weighted and aggregated to provide single score LCA results. The overall findings showed that electricity consumption and condensates included VFAs, as well as enzymes, yeast, and n-hexane, were the main contributo... [more]

With the proliferation of e-commerce, the field of last-mile logistics has grown increasingly, highlighting the need to manage the environmental consequences of this phenomenon, especially to achieve decarbonization targets for cities and to improve citizens’ quality of life. Within this framework, the authors carried out a last-mile logistics life cycle assessment, to analyse and compare different logistics vehicle options performing the same service in an urban context: an electric four-wheel cargo bike, an electric van, a plug-in hybrid van, and a diesel van. The assessment shows that the e-cargo bike performs better for all the impact categories considered. The second-best option is the e-van, while the diesel van shows the worst environmental results. Focusing on decarbonization, the replacement of a diesel van with an electric one or with an e-cargo bike allows a reduction of 173 g CO2 eq/km and 250 g CO2 eq/km, respectively. Similar results are obtained for Photochemical Ozone F... [more]

Are small-scale wind turbines green? In this study, we perform a ‘cradle to grave’ life cycle assessment of a novel domestic-scale 10 kW vertical axis wind turbine tree which uses combined Savonius and H-Darrieus blades. Situated at a test site in Surat Thani, Thailand, SimaPro software was used to evaluate the environmental impact profile of the tree. Comparisons to the Thai grid mix were made, using both with and without end-of-life treatments. Impact profiles were calculated using wind data collected over two years at Surat Thani, and from wind data from a higher capacity factor (CF) site at Chiang Mai, Thailand. Energy and greenhouse gas payback times were estimated for both locations. The relative magnitudes of impacts were compared with environmental prices protocol, and we investigated reductions in impacts using three mitigative scenarios: changes to design, transportation and materials. The results showed that Chiang Mai had a CF = 7.58% and Surat Thani had a CF = 1.68%. A tot... [more]

In the transition towards a sustainable world with a “green horizon” (something that is also of great importance to the policy of energy self-sufficiency in housing and self-consumption), geothermal energy is seen as quite a feasible alternative for single-family homes. This article focuses on a comparison between the environmental impact and life cycle analysis of three alternatives and provides a base case for the replacement of a conventional type of boiler with a geothermal one for a typical house located in a Mediterranean climate. The first alternative (A) consists of a horizontal catchment system through a field of geothermal probes. The second alternative (B) is a shallow water catchment system, open type, with the return of water to a nearby river. The third option studied (C) is also a shallow water catchment system but with the water, return injected into a well downstream to the underground water flow. The study shows that alternatives A and B have the least environmental i... [more]

This study aims to investigate, from a technical and an environmental perspective, various alternatives for acetic acid concentration for maximizing acetic acid production, its purity, and in the meantime, minimizing the energy usage and the environmental impact. Liquid−liquid extraction followed by azeotropic distillation using different solvents such as: (i) ethyl acetate, (ii) isopropyl acetate, and (iii) a mixture containing isopropyl acetate and isopropanol were first explored, using process flow modeling software. The three cases were compared considering various technical key performance indicators (i.e., acetic acid flow-rate, acetic acid purity, acetic acid recovery, power consumption, thermal energy used, and number of equipment units involved) leading to the conclusion that the usage of the isopropyl acetate—isopropanol mixture leads to better technical results. The isopropanol-isopropyl acetate mixture was furthermore investigated in other two cases where process intensific... [more]

Straw bale building construction is attracting a revived public interest because of its potential for reduced carbon footprint, hygrothermal comfort, and energy savings at an affordable price. The present paper aims to summarize the current knowledge on straw bale construction, using available data from academic, industry, and public agencies sources. The main findings on straw fibers, bales, walls, and buildings are presented. The literature shows a wide variability of results, which reflects the diversity of straw material and of straw construction techniques. It is found that the effective thermal conductivity, density, specific heat, and elastic modulus of straw bales used in construction are in the range 0.033−0.19 W/(m·K), 80−150 kg/m3, 1075−2000 J/(kg·K), and 150−350 kPa respectively. Most straw-based multilayered walls comply with fire resistance regulations, and their U-value and sound reduction index range from 0.11 to 0.28 W/m2 K and 42 to 53 dB respectively, depending on th... [more]

Technologies that use renewable energy sources (RES) are crucial to achieving decarbonization goals, but a significant number of studies show their relatively high environmental impact during the production phase. Therefore, technologies need to be compared in terms of their life-cycle environmental impact. The life cycle analysis (LCA) methodology is well known and widely employed. However, problems related to the methodological choices prevent taking full advantage of the LCA, as the results of numerous studies are often incomparable. The presented review aims to critically compare the impact of different energy generation technologies—RES (as well as non-RES) energy generators and co-generators. The numeric results are structured and analyzed in terms of the global warming potential (GWP) and non-RES primary energy consumption. The results show that RES technologies are superior compared to conventional fossil-fuel-based systems in most cases, and the high impact during the producti... [more]

This study quantitively estimates the energy and environmental impacts of China’s promotion of battery electric vehicles (BEVs) in the context of banning the sale of gasoline vehicles (GVs). Combining the population ecological growth model and the life cycle assessment method, the potential of BEVs promotion in reducing fossil energy (FE) consumption and greenhouse gas (GHG) emissions under different timings of banning GV sales was dynamically simulated and analyzed. The results show that the current life cycle FE consumption and GHG emissions of BEVs are approximately 40.1% and 26.6% lower than those of GVs, respectively. Based on the development of automobile technology and the national energy plan, replacing GVs with BEVs can reduce GHG emissions and FE consumption by up to 43.61−55.81% and 46.33−55.45%, respectively. Compared with the scenario without BEV promotion, if sales of GVs in China are banned between 2040 and 2060, the point at which the carbon peak of the automobile marke... [more]

Globally, rising population and rapid urbanisation have resulted in the dual issues of increased electricity demand and waste generation. These exacerbate diverse global problems, ranging from irregular electricity supply and inadequate waste management systems to water/air/soil pollution, climate change, etc. Waste-to-Energy (WtE) approaches have been proposed and developed to address simultaneously these two issues through energy recovery from waste. However, the variety of available waste materials and different WtE technologies make the choice of an appropriate technology challenging for decision-makers. The evaluation of the different WtE technologies in terms of their sustainability could provide a solid comparative base for strategic decision making in the power and waste management domains. This paper presents research conducted using a multidimensional Life Cycle Sustainability Assessment (LCSA) approach to estimate and compare the environmental, economic, and social impacts a... [more]

Moving towards RER has become imperative to achieve sustainable development goals (SDG). Renewable energy resources (RER) are characterized by uncertainty whereas, most of them are unpredictable and variable according to climatic conditions. This paper focuses on RER-based electrical power plants as a base to achieve two different goals, SDG7 (obtaining reasonably priced clean energy) and SDG13 (reducing climate change). These goals in turn would support other environmental, social, and economic SDG. This study is constructed based on two pillars which are technological developments and life cycle assessment (LCA) for wind, solar, biomass, and geothermal power plants. To support the study and achieve the main point, many essential topics are presented in brief such as fossil fuels’ environmental impact, economic sustainability linkage to RER, the current contribution of RER in energy consumption worldwide and barriers and environmental effects of RER under consideration. As a result, s... [more]

The international energy scenario to date is heavily based on fossil energy sources such as coal, oil or natural gas. According to the international ecological goals of the UNFCCC formalized in the legally binding treaty called the Paris Agreement, the next global challenges will be the decommissioning, dismantling or reconversion of the current fossil energy system into a new, more sustainable system that makes more efficient use of renewable energy technologies. Worldwide, there are about 6500 offshore oil and gas facilities and about 130 of them are located in the Mediterranean basin, mainly in the Adriatic and Ionian Seas: more than 110 offshore gas platforms have been installed in these areas since 1960. In this paper, using Life Cycle Assessment, the environmental and economic impacts of the total removal operations of an existing offshore platform in the context of the Adriatic Sea are assessed based on existing and registered decommissioning projects. In addition, the avoided i... [more]

The world is moving towards a low-carbon economy through renewable energy sources. In this context, concentrating solar power (CSP) technologies can exploit the rich solar resource in Brazil, diversifying the national electricity mix. The aim of this paper is to support the insertion of CSP generation in the Brazilian bottom-up model MATRIZ by analyzing the environmental performance of three CSP technologies: (i) solar tower power (STP) with a thermal storage system (TSS) of 7.5 h; (ii) solar thermal parabolic trough (STPT) with a TSS of 6 h; and (iii) STPT without TSS. From a life cycle perspective, their freshwater consumption and greenhouse gas (GHG) emissions are addressed by employing the software SimaPro, the Ecoinvent database, and the ReCiPe 2016 method, as well as information from the system advisory model (SAM) and the literature. As a result, STP is the most environmentally sound CSP alternative, presenting lower GHG emissions and water consumption than the two STPT technolo... [more]

The decarbonization of electrical power generation systems is one of Singapore’s national political agendas to reduce national greenhouse emissions. LCA is applied to assess the trade-offs of national implementation of electricity generation from conventional fossil-fuel power plants, compared to low-carbon alternatives. The first aim of LCA is to quantify the emission inventory of national electrical generation within the geographical boundary of Singapore, and next to generate the potential environmental impacts of Global Warming Potential, Acidification, and Eutrophication. Various scenarios are tested for a projected diversity of fuel resource mixes considered for years 2030 and 2040 and a hypothetical scenario where 100% renewable energy is employed and imported as the nation transitions towards a low-carbon energy future. Further discussions on the additional LCA model indicators should be included for the potential of low-carbon hydrogen application.

Methane from environmentally friendly anaerobic digestion may be an alternative non-renewable source that is depleting. One of the substrates for that process may be lignocellulose-based materials. The article concerns comparing the environmental impact as well as technical and energy indicators of alternative ways of producing methane from the anaerobic digestion of Pennisetum hybrid. Five scenarios were analyzed: methane production from the anaerobic digestion of the raw grass, the grass subjected to alkaline pretreatment (with 2% NaOH solution at two temperatures), and the grass subjected to mechanical pretreatment (ground to obtain particle sizes <0.18 mm and 0.25−0.38 mm). Multi-criteria decision (MCA) analysis was carried out with the use of five indicators, including life cycle assessment results as well as methane production parameters, in order to optimize this sustainable way of bioenergy production. The purpose of this study was to identify the most cost-effective and env... [more]

This study aims to create a comprehensive, holistic approach to evaluate the environmental, energy, and economic impacts of air source heat pump deployment scenarios through: (i) a life cycle assessment of air source heat pumps in Orkney houses, (ii) energy systems optimisation modelling to optimise the performance of an air source heat pump coupled with thermal energy storage tank to reduce use phase related impacts in Orkney, (iii) modelling of Orkney’s domestic building stock to understand the housing condition, and (iv) economic modelling to analyse the life cycle cost of an air source heat pump and potential savings when replacing conventional heating systems. The results show that an 82% reduction in energy supply could be achieved when ambitious energy efficiency improvement measures are adopted in the circular economy scenario. The use phase related emissions could be reduced by 98% when the air source heat pump becomes the only heating technology in Orkney. However, the life c... [more]

The gasification of Polish coal to produce hydrogen could help to make the country independent of oil and gas imports and assist in the rational energy transition from gray to green hydrogen. When taking strategic economic or legislative decisions, one should be guided not only by the level of CO2 emissions from the production process, but also by other environmental impact factors obtained from comprehensive environmental analyses. This paper presents an analysis of the life cycle of hydrogen by coal gasification and its application in a vehicle powered by FCEV cells. All the main stages of hydrogen fuel production by Shell technology, as well as hydrogen compression and transport to the distribution point, are included in the analyses. In total, two fuel production scenarios were considered: with and without sequestration of the carbon dioxide captured in the process. Life cycle analysis was performed according to the procedures and assumptions proposed in the FC-Hy Guide, Guidance D... [more]

(1) Background: The embodied energy of building materials is a significant contributor to climate change, in tandem with the energy use intensity (EUI). Yet, studies on the material impacts of European retail buildings, namely with relation to EUI, are missing. Hence, this study set out to: (i) evaluate the embodied energy and carbon emissions for a European retail building; (ii) quantify the material flow in terms of mass; (iii) compare the embodied aspects to the operational EUI and carbon use intensity (CUI); (iv) assess building materials with higher impacts; and (v) investigate strategies to mitigate materials’ impacts. (2) Methods: A Portuguese retail building was selected as a case study. A simplified LCA method was followed (cradle-to-gate), analysing the shell building materials in terms of primary energy demand and global warming potential. (3) Results: the embodied energy represented 32% of total lifecycle energy while the embodied carbon represented 94%. EUI was 1×kWh/m2/y... [more]

This work assesses the energy requirements and CO2 emissions of a building made of Lime Hemp Concrete (LHC) with alternative unfired binders as lime replacement, compared to buildings made of standard LHC, and several conventional building materials. The assessment is based on ISO 14040, which deals with Life Cycle Assessment (LCA), and examines two aspects: energy, including pre-use phase Embodied Energy (EE), and use phase Operational Energy (OE); and CO2 emissions, including pre-use phase Embodied Carbon (EC), and use phase Operational Carbon (OC). The EE and EC calculations are based on published databases, while OE and OC were obtained with EnergyPlus simulations. The assessment refers to a specific case study in an arid region, with extreme diurnal and seasonal fluctuations of temperature and relative humidity. Using LHC with 100% unfired binder as lime replacement was shown to save up to 90% of the total energy consumption and CO2 emissions, as compared to conventional building... [more]