Specification for the assessment of greenhouse gas (GHG) emissions from the whole life cycle of textile products

2014 ◽  
Author(s):  
S.F. Ledgard ◽  
C. Basset-Mens ◽  
S. Mclaren ◽  
M. Boyes

Assessment of energy use and greenhouse gas emissions associated with dairy products needs to account for the whole life cycle of the products, particularly with the debate about "food miles"(the transportation of product from producer to consumer). A life cycle assessment (LCA) of an average NZ dairy farm for 2005 showed that total energy use per kg milk from the "cradle-tomilk- in-the-vat" was 45-65% of that from EU farms. The greenhouse gas (GHG) emissions or carbon footprint showed similar relative trends although differences were smaller due, at least in part, to lower methane efficiency from lower-producing NZ cows. Energy use associated with shipping dairy product (e.g. cheese) from NZ to UK is equivalent to about one-quarter of the on-farm use. Even when added together, the energy use from the NZ farm and from shipping would still be less than onfarm energy use for the EU farms. However, this is affected by intensification and the Dexcel Resource Efficient Dairying trial showed that increasing maize silage use, and nitrogen fertiliser use in particular, increased the energy use and GHG emissions per kg milk by up to 190% and 23%, respectively. Thus, the trend for intensification on NZ dairy farms means that our comparative advantage with EU farms is diminishing. A focus on improved farm system practices and integration of mitigation options is required to reverse this trend. Keywords: food miles, greenhouse gases, energy, life cycle assessment, milk, New Zealand, efficiency


2008 ◽  
Vol 57 (11) ◽  
pp. 1683-1692 ◽  
Author(s):  
Andrea Tilche ◽  
Michele Galatola

Anaerobic digestion is a well known process that (while still capable of showing new features) has experienced several waves of technological development. It was “born” as a wastewater treatment system, in the 1970s showed promise as an alternative energy source (in particular from animal waste), in the 1980s and later it became a standard for treating organic-matter-rich industrial wastewater, and more recently returned to the market for its energy recovery potential, making use of different biomasses, including energy crops. With the growing concern around global warming, this paper looks at the potential of anaerobic digestion in terms of reduction of greenhouse gas (GHG) emissions. The potential contribution of anaerobic digestion to GHG reduction has been computed for the 27 EU countries on the basis of their 2005 Kyoto declarations and using life cycle data. The theoretical potential contribution of anaerobic digestion to Kyoto and EU post-Kyoto targets has been calculated. Two different possible biogas applications have been considered: electricity production from manure waste, and upgraded methane production for light goods vehicles (from landfill biogas and municipal and industrial wastewater treatment sludges). The useful heat that can be produced as by-product from biogas conversion into electricity has not been taken into consideration, as its real exploitation depends on local conditions. Moreover the amount of biogas already produced via dedicated anaerobic digestion processes has also not been included in the calculations. Therefore the overall gains achievable would be even higher than those reported here. This exercise shows that biogas may considerably contribute to GHG emission reductions in particular if used as a biofuel. Results also show that its use as a biofuel may allow for true negative GHG emissions, showing a net advantage with respect to other biofuels. Considering also energy crops that will become available in the next few years as a result of Common Agricultural Policy (CAP) reform, this study shows that biogas has the potential of covering almost 50% of the 2020 biofuel target of 10% of all automotive transport fuels, without implying a change in land use. Moreover, considering the achievable GHG reductions, a very large carbon emission trading “value” could support the investment needs. However, those results were obtained through a “qualitative” assessment. In order to produce robust data for decision makers, a quantitative sustainability assessment should be carried out, integrating different methodologies within a life cycle framework. The identification of the most appropriate policy for promoting the best set of options is then discussed.


2020 ◽  
Vol 12 (18) ◽  
pp. 7302
Author(s):  
Anne Magdalene Syré ◽  
Florian Heining ◽  
Dietmar Göhlich

The transport sector in Germany causes one-quarter of energy-related greenhouse gas emissions. One potential solution to reduce these emissions is the use of battery electric vehicles. Although a number of life cycle assessments have been conducted for these vehicles, the influence of a transport system-wide transition has not been addressed sufficiently. Therefore, we developed a method which combines life cycle assessment with an agent-based transport simulation and synthetic electric-, diesel- and gasoline-powered vehicle models. We use a transport simulation to obtain the number of vehicles, their lifetime mileage and road-specific consumption. Subsequently, we analyze the product systems’ vehicle production, use phase and end-of-life. The results are scaled depending on the covered distance, the vehicle weight and the consumption for the whole life cycle. The results indicate that the sole transition of drive trains is insufficient to significantly lower the greenhouse gas emissions. However, sensitivity analyses demonstrate that there is a considerable potential to reduce greenhouse gas emissions with higher shares of renewable energies, a different vehicle distribution and a higher lifetime mileage. The method facilitates the assessment of the ecological impacts of complete car-based transportation in urban agglomerations and is able to analyze different transport sectors.


2017 ◽  
Vol 898 ◽  
pp. 1963-1969 ◽  
Author(s):  
Yan Qiong Sun ◽  
Yu Liu ◽  
Su Ping Cui

The development and application of light aggregate concrete blocks are considered as one of the key issue that promote the energy saving and emission reduction in construction and building materials industries. In this paper, the greenhouse gas (GHG) emissions of light aggregate concrete blocks during the whole life cycle were analyzed based on life cycle assessment (LCA) methodology. The results demonstrated that the amount of GHG emissions of the light aggregate concrete block was 174 kg/m3 in the system boundary of ‘from cradle to gate’. The direct GHG emissions was 51.31 kg/m3 accounting for 28.46% of the aggregate emission, while the indirect GHG emissions was 124 kg/m3. The cement production and the concrete block production were the main contributors to the total emissions. According to the sensitivity analysis, the GHG emissions amount was quite sensitive to the amount of cement and ceramsite consumption.


Author(s):  
Ching-Shin Norman Shiau ◽  
Scott B. Peterson ◽  
Jeremy J. Michalek

Plug-in hybrid electric vehicle (PHEV) technology has the potential to help address economic, environmental, and national security concerns in the United States by reducing operating cost, greenhouse gas (GHG) emissions and petroleum consumption from the transportation sector. However, the net effects of PHEVs depend critically on vehicle design, battery technology, and charging frequency. To examine these implications, we develop an integrated optimization model utilizing vehicle physics simulation, battery degradation data, and U.S. driving data to determine optimal vehicle design and allocation of vehicles to drivers for minimum life cycle cost, GHG emissions, and petroleum consumption. We find that, while PHEVs with large battery capacity minimize petroleum consumption, a mix of PHEVs sized for 25–40 miles of electric travel produces the greatest reduction in lifecycle GHG emissions. At today’s average US energy prices, battery pack cost must fall below $460/kWh (below $300/kWh for a 10% discount rate) for PHEVs to be cost competitive with ordinary hybrid electric vehicles (HEVs). Carbon allowance prices have marginal impact on optimal design or allocation of PHEVs even at $100/tonne. We find that the maximum battery swing should be utilized to achieve minimum life cycle cost, GHGs, and petroleum consumption. Increased swing enables greater all-electric range (AER) to be achieved with smaller battery packs, improving cost competitiveness of PHEVs. Hence, existing policies that subsidize battery cost for PHEVs would likely be better tied to AER, rather than total battery capacity.


2011 ◽  
Vol 133 (8) ◽  
Author(s):  
Ching-Shin Norman Shiau ◽  
Jeremy J. Michalek

We pose a reformulated model for optimal design and allocation of conventional (CV), hybrid electric (HEV), and plug-in hybrid electric (PHEV) vehicles to obtain global solutions that minimize life cycle greenhouse gas (GHG) emissions of the fleet. The reformulation is a twice-differentiable, factorable, nonconvex mixed-integer nonlinear programming (MINLP) model that can be solved globally using a convexification-based branch-and-reduce algorithm. We compare results to a randomized multistart local-search approach for the original formulation and find that local-search algorithms locate global solutions in 59% of trials for the two-segment case and 18% of trials for the three-segment case. The results indicate that minimum GHG emissions are achieved with a mix of PHEVs sized for 25–45 miles of electric travel. Larger battery packs allow longer travel on electrical energy, but production and weight of underutilized batteries result in higher GHG emissions. Under the current average U.S. grid mix, PHEVs offer a nearly 50% reduction in life cycle GHG emissions relative to equivalent conventional vehicles and about 5% improvement over HEVs when driven on the standard urban driving cycle. Optimal allocation of different PHEVs to different drivers turns out to be of second order importance for minimizing net life cycle GHGs.


2020 ◽  
Vol 12 (12) ◽  
pp. 5144 ◽  
Author(s):  
Dahye Kim ◽  
Kyung-Tae Kim ◽  
Young-Kwon Park

The purpose of this study is to compare the effect of a reduction in greenhouse gas (GHG) emissions between the combined heat and power (CHP) plant and boiler, which became the main energy-generating facilities of “anaerobic digestion” (AD) biogas produced in Korea, and analyze the GHG emissions in a life cycle. Full-scale data from two Korean “wastewater treatment plants” (WWTPs), which operated boilers and CHP plants fueled by biogas, were used in order to estimate the reduction potential of GHG emissions based on a “life cycle assessment” (LCA) approach. The GHG emissions of biogas energy facilities were divided into pre-manufacturing stages, production stages, pretreatment stages, and combustion stages, and the GHG emissions by stages were calculated by dividing them into Scope1, Scope2, and Scope3. Based on the calculated reduction intensity, a comparison of GHG reduction effects was made by assuming a scenario in which the amount of biogas produced at domestic sewage treatment plants used for boiler heating is replaced by a CHP plant. Four different scenarios for utilizing biogas are considered based on the GHG emission potential of each utilization plant. The biggest reduction was in the scenario of using all of the biogas in CHP plants and heating the anaerobic digester through district heating. GHG emissions in a life cycle were slightly higher in boilers than in CHP plants because GHG emissions generated by pre-treatment facilities were smaller than other emissions, and lower Scope2 emissions in CHP plants were due to their own use of electricity produced. It was confirmed that the CHP plant using biogas is superior to the boiler in terms of GHG reduction in a life cycle.


Author(s):  
Viktoras Vorobjovas ◽  
Algirdas Motiejunas ◽  
Tomas Ratkevicius ◽  
Alvydas Zagorskis ◽  
Vaidotas Danila

Climate change is one of the main nowadays problem in the world. The politics and strategies for climate change and tools for reduction of greenhouse gas (GHG) emissions and green technologies are created and implemented. Mainly it is focused on energy, transport and construction sectors, which are related and plays a significant role in the roads life cycle. Most of the carbon footprint emissions are generated by transport. The remaining emissions are generated during the road life cycle. Therefore, European and other countries use methods to calculate GHG emissions and evaluate the impact of road construction methods and technologies on the environment. Software tools for calculation GHG emissions are complicated, and it is not entirely clear what GHG emission amounts generate during different stages of road life cycle. Thus, the precision of the obtained results are often dependent on the sources and quantities of data, assumptions, and hypothesis. The use of more accurate and efficient calculation-evaluation methods could let to determine in which stages of road life cycle the largest carbon footprint emissions are generated, what advanced road construction methods and technologies could be used. Also, the road service life could be extended, the consumption of raw materials, repair, and maintenance costs could be reduced. Therefore the time-savings could be improved, and the impact on the environment could be reduced using these GHG calculation-evaluation methods.


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