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2021 ◽  
Vol 2 ◽  
Author(s):  
Frans J. Jordaan ◽  
Frederick W. C. Neser ◽  
Azwihangwisi Maiwashe ◽  
Zelda King ◽  
Michiel M. Scholtz

Any reduction in the carbon footprint of beef production will contribute to future sustainability. This study investigates the environmental impact (carbon footprint) of the changes that occurred in cow productivity in the cowherds of four South African landrace breeds over a period of 25–30 years. Cow productivity, defined as kilogram calf weaned per large stock unit mated, increased by 18.3, 10.0, 14.2, and 10.4% in the Afrikaner, Bonsmara, Drakensberger, and Nguni, respectively. This resulted in a decrease in the carbon footprint, as defined by the enteric methane emissions factor, of between 6.6 and 12.0%. Changes in the cow productivity component traits, viz. weaning weight, cow weight, and fertility (as measured by inter-calving period) was also investigated. In all breeds, except the Nguni, the change in the environmental trends were less than that of the direct genetic or phenotypic trends. The genetic trends for direct weaning weight in the Afrikaner, Bonsmara, and Drakensberger were +6.7, +11.7, and +6.2 kg, respectively. In the case of the Bonsmara and Drakensberger breeds, the genetic trends were larger than the phenotypic trends, which may indicate that the environment cannot support the higher “genetic” weaning weights. The genetic trends for mature cow weight in Bonsmara and Drakensberger were +15.9 and +15.1 kg, respectively, whereas in the Afrikaner and Nguni it was not significantly different from zero (R2 ≤ 0.24). The trends in the phenotypic mature cow weights were −8.3, +17.5, +8.5, and −17.2 kg for in the Afrikaner, Bonsmara, Drakensberger, and Nguni, respectively. Although the observed inter-calving period of all breeds declined, there was no genetic change in inter-calving period for any of the breeds. It is proposed that selection indices are developed for cow productivity, which can be extended to a carbon footprint selection index. It is recommended that similar studies be done on all the major beef breeds in South Africa, especially those that rely on regular importation of genetic material.


Author(s):  
Nunzia Ciriello ◽  
Lorenza Albano ◽  
Giuseppe Auriemma ◽  
Raffaele Palomba ◽  
Giuseppe Grazioli ◽  
...  

The environmental impact of greenhouse gases caused by livestock farms plays a fundamental role due to the implications and environmental consequences that livestock practices entail, affecting the stability of the entire ecosystem connected to them, especially as a consequence of the growing demand for products of animal origin. The aim of this work was to quantify the CH4 emissions factor in lactating buffaloes by comparing four different types of livestock management: family, conventional, organic and sustainable. To determine the enteric CH4 emissions from buffalo, information about animal production and farm management was analyzed, and the CH4 emission factor was calculated using the IPCC Tier 2 model. ANOVA was conducted to evaluate significant differences between the farms; Pearson’s correlation was used to evaluate the relationship between parameters. In a conventional farm, the CH4 emission factor for buffalo was 27.69 kg CH4/head/yr compared to 22.77 and 21.61 kg CH4/head/yr respectively for organic and family-run. These data may also depend on the higher protein and fiber content in the administered unifeed. Furthermore, the ratio of enteric emissions factor of CH4 / gross energy intake ratio reflected these data (12.04 vs 10.93 vs 10.16 vs 10.65 for conventional, organic, sustainable, and family-run farms, respectively).


2020 ◽  
pp. 014459872097337
Author(s):  
Haining Wang ◽  
Hong Zhang ◽  
Keming Hou ◽  
Gang Yao

This study focuses on the calculation of carbon emissions during prefabricated component transportation phase, figuring out how to accurately infer the carbon emissions factor according to the changing of external factors. Through tracking and analyzing the differences between prefabricated component transportation phase and ordinary building material transportation phase, this paper explores how to establish a calculation mathematical model of carbon emissions factor to reflect the real prefabricated component transportation phase, that work would critically lower the bias of component transportation carbon emissions factors between in real world and giving in relevant national standards. The research content involved in this paper provides quantitative scale for Architecture Engineering and Construction (AEC), and also helps to establish and popularize carbon sink system of Architecture Engineering and Construction (AEC). In this study, prefabricated component, the basic component of assembled building, is taken as the research object and clue. The real carbon emissions performances of transport vehicles loaded with different number of components are simulated, and the carbon emissions factor and related parameter groups of transport vehicles are measured experimentally. Based on the statistical method, the data parameter selection and regression analysis are carried out by using STATA® 12. The relationship between the three parameters of Load Ratio, Average Speed and Atmospheric Temperature on carbon emissions factor are obtained except the types of vehicles. It is found that there is a linear relationship between the carbon emissions factor and the −0.5 power of the Load Ratio, the square of the Atmospheric Temperature and the reciprocal of the Average Speed, and the R2 value of the fitting formula reaches 90.46%. The result has a good interpretation for the measured data, better reflect the real situation of carbon emissions for assembled building during prefabricated component transportation phase, and improve the accuracy of carbon emissions calculation in this phase. If the Load Ratio and Average Speed can be increased, and the transportation time of prefabricated component at lower temperature can be selected, the carbon emissions can be significantly reduced, that could exert positive influence to the environment.


2020 ◽  
Vol 12 (15) ◽  
pp. 6276
Author(s):  
Seongmin Kang ◽  
Yoonjung Hong ◽  
Moon Soon Im ◽  
Seong-Dong Kim ◽  
Eui-Chan Jeon

In this study, measurement methods for estimating the NH3 emissions in barns and the development of different emission factors were reviewed, and the factors to be considered when applying a dynamic flux chamber approach were analyzed. First, one of the factors to be considered when applying the dynamic flux chamber was determined as the stabilization time in the chamber. As a result of the experiment, it was confirmed that the concentration in the chamber stabilized after 45 min. This is considered to take longer than the stabilization time of 20 min suggested in the previous study. The second is the choice of the measurement method. This method includes real-time measurement and the indophenol method. As a result of the experiment in both methods, the ammonia flux showed a difference of about 10%, so both methods are considered to be considered. Therefore, it is judged that the methodology should be selected according to the situation, such as weather or electric power secured at the barn site. In the future, if studies on whether the stabilization time in the chamber can be changed according to seasonal factors and ambient temperature, and based on a sufficiently large sample size, the results will contribute to improving the reliability of the estimated ammonia(NH3) emissions and the development of an emissions factor for use in the livestock sector in Korea.


2020 ◽  
Vol 15 (1) ◽  
pp. 169-177
Author(s):  
Jakub Siemek ◽  
◽  
Jan Macuda ◽  
Łukasz Łukańko ◽  
Jakub Nowak ◽  
...  

Biomass is an important element in the energy balance in the world and plays a large role in efforts to reduce greenhouse gas emissions, and by this is a sustainable source of energy. One method of using biomass is through co-firing with hard coal and lignite in order to generate electricity. An important factor promoting the use of biomass in European Union countries is the fact that CO2 emissions from combustion are not included in the sum of emissions from fuel combustion, in accordance with the principles established in the emission trading system EU ETS. The aim of our research was to examine the possibility of using winter oilseed rape for energy purposes, grown in three research centres located in southern Poland. Two varieties of winter oilseed rape, Adam and Poznaniak, were used during laboratory tests. Analyses were carried out for siliques, seeds, and the main and lateral stem. As part of the study, the calorific value and heat of combustion were determined for 20 samples of winter oilseed rape. The highest values were obtained for seeds, while the lowest were obtained for stems. The calculated values of carbon dioxide emissions factor for the analysed samples were in most cases above 100 kg/GJ and were much higher than the emission during hard coal combustion. In addition, as part of the study, the biomass moisture, amount of ash generated in the combustion process, and the content of volatile compounds as well as carbon and sulphur were determined.


2019 ◽  
Vol 5 (1) ◽  
pp. 47
Author(s):  
Alfredo Marvão Pereira ◽  
Rui Marvão Pereira

<p><em>We estimate the effects of infrastructure investments on industrial CO<sub>2</sub> emissions in Portugal based on the economic effects of twelve types of infrastructure investments on twenty-two different industries and the industry-specific CO<sub>2</sub> emission factors. Our conclusions are as follows. First, most infrastructure investments help the emissions intensity of the economy. The exceptions are investments in airports and healthcare. Second, the economic effects of the different types of infrastructure investments on the electrical power industry are central in determining the overall effects on emissions. Indeed, electric power accounts for 35% of CO<sub>2</sub> emissions and has extremely high emissions factor. Third, if the emissions from electricity generation were eliminated, most infrastructure investments would still lead to a decline in emissions intensity. Investments in national roads would leave the emissions intensity unchanged while investments in healthcare have adverse effects. There are several important policy implications of these results. Given the present electric generating mix, investment in national roads are appropriate from an environmental perspective, while investments in airport infrastructure are not. Under a scenario of aggressive use of renewable energy sources in electricity generation, however, the best investments would be in railroads and airports, two industries highly dependent on the use of electricity. </em></p>


2018 ◽  
Vol 10 (7) ◽  
pp. 2467 ◽  
Author(s):  
Carlos Llano ◽  
Santiago Pérez-Balsalobre ◽  
Julian Pérez-García

Greenhouse Gas (GHG) emissions is a topic of major concern worldwide. Following previous articles which provide a methodology for estimating GHG emissions associated with international trade by transport mode at the world level, in this paper, we estimate an equivalent database of GHG emissions for inter-regional trade flows within a country (Spain). To this end, we built a new database of GHG emissions for origin–destination flows between Spanish provinces during 1995–2015. For each year, we combine industry-specific flows by four transport modes (road, train, ship and aircraft) with the corresponding GHG emissions factor for each mode in tons*km, drawn from the specialized literature. With this dataset of GHG emissions, we generate and analyze the temporal, sectoral and spatial pattern of Spanish inter-regional GHG flows. We then forecast emissions for 2016–2030 and consider how transport mode shifts might produce a more sustainable freight system within the country through the substitution of environmentally friendly alternatives (railway) for specific origin–destination–product flows in high-polluting modes (road).


2018 ◽  
Vol 39 (2) ◽  
pp. 196-210 ◽  
Author(s):  
Barny Evans ◽  
Sabbir Sidat

This paper is an investigation into the issues around how we calculate CO2 emissions in the built environment. At present, in Building Regulations and GHG Protocol calculations used for buildings and corporate CO2 emissions calculations, it is standard to use a single number for the CO2 emission factor of each source. This paper considers how energy demand, particularly electricity at different times of the day, season and even year can differ in terms of its CO2 emissions. This paper models three different building types (retail, office and home) using standard software to estimate a profile of energy demand. It then considers how CO2 emissions calculations differ between using the single standard emissions factor and using an hourly emissions factor based on real electrical grid generation over a year. The paper also examines the impact of considering lifetime emissions factors rather than one-year factors using UK government projections. The results show that there is a significant difference to the analysis of benefit in terms of CO2 emissions from different measures – both intra- and inter-year – due to the varying CO2 emissions intensity, even when they deliver the same amount of net energy saving. Other factors not considered in this paper, such as impact on peak generation and air quality, are likely to be important when considering whole-system impacts. In line with this, it is recommended that moves are made to incorporate intra- and inter-year emissions factor changes in methodologies for calculating CO2 emissions. (This is particularly important as demand side response and energy storage, although generally accepted as important in the decarbonisation of the energy system at present will show as an increase in CO2 emissions when using a single number.) Further work quantifying the impact on air quality and peak generation capacity should also be considered. Practical application: This paper aims to help practitioners to understand the performance gap between how systems need to be designed in order to meet regulations compared to how buildings perform in reality – both today and in the future. In particular, it considers the use of ‘real-time’ carbon factors in order to attain long-term CO2 reductions. This methodology enables decision makers to understand the impacts of different energy reduction technologies, considering each of their unique characteristics and usage profiles. If implemented, the result is a simple-to-use dataset which can be embedded into the software packages already available onto the market which mirrors the complexity of the electricity grid that is under-represented through the use of a static carbon figure.


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