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Bigger, better, slower, less: a longitudinal case study on the energy efficiency of a global supply chain
No full textSupply chains are highly dependent upon energy that is generated by fossil fuels, but only recently
researchers focused on how demand levels of energy in supply chains depend on supply chain strategies and
structures (e.g. time-based strategies, global sourcing arrangements etc.) as “generative mechanisms” that
influence this demand. Compatibility of global and green supply chain management appears especially critical
and trade-offs between economic performance (costs, service levels, sales), energy efficiency, environmental
performance are often discussed. This paper presents a quantitative, longitudinal analysis of energy
performance indicators and inbound logistics strategy of a company which, in the last few years, reached a
“bigger”, global sourcing area achieving “better” productivity and sales performances and at the same time
using “less” primary energy for transport. Reducing frequency of deliveries and making up for “slower”
deliveries from farthest suppliers with higher inventories appears a means to improve both economic and
energy efficiency performances in supply chains under present economic conditions
Prospect for agricultural biogas as a vehicle fuel in Northern Italy
Full text linkIn recent years, Italy has become the third largest agricultural biogas producer in the world after China and Germany.
The utilization of biogas in the country is still restricted to power generation with limited use of cogenerated heat, whereas other utilization pathways focusing on biogas upgrading to biomethane remain unexplored.Given the high development of natural gas pipelines and the presence of numerous compressed natural gas (CNG) refuelling sta- tions in Northern Italy, significant market opportunities for biogas may also arise in the transport sector.
The use of biomethane as a vehicle fuel offers several advantages compared with other biofuels, such as first-generation bioethanol and biodiesel, the most prominent of which being a more favourable energy balance and the possibility of adopting a wide variety of organic materials for its production. However, the requirement to upgrade the biogas to biomethane of adequate quality for transport fuel use, the compression of the gas for storage and transport, and the lack of refuelling infrastructure, represent significant barriers to the deployment of biogas-based vehicle fuels in many European countries.
In this thesis, prospects for agricultural biogas in Northern Italy have been explored. The focus is on its utilization as compressed biomethane for vehicles (CBM), as com- pared to other utilization pathways (i.e. power only option, simultaneous production of electricity and heat and injection of biomethane into the national gas grid).
The methodology considers the use of different spatially explicit optimization models to forecast future biogas supply chain structures that minimize overall costs and en- vironmental impact. Previous and actual biogas promotion schemes and other policy instruments to foster the production of biomethane as a vehicle fuel have been included in the assessment and applied to regional as well as macro regional case studies.
The results show that upgrading biogas for transport applications carries some envi- ronmental advantages, especially compared with its utilization solely for the production of electricity. However, promoting the development of a biomethane market solely with the introduction of environmental taxes is the least effective option as the environmental benefit in terms of emissions mitigation is very little. On the other hand, the intro- duction of current biogas incentive mechanisms would favour the development of CMB technologies in areas with promising biomethane market potentials
Optimal location, technology and capacity planning of biogas production and utilization plants
Full text linkIn December 2013, the Italian Ministry for Economic Development finally started the long-awaited incentive program for biomethane grid injection and biomethane for transportation, which opens up new opportunities for alternative applications of biogas which are expected to bring additional environmental benefits. Because of the wider range of feasible options and of the increased complexity of incentive structures, identifying most suitable alternatives becomes more and more difficult for entrepreneurs and local authorities. Biomass feedstock is a scarce resource and the profitability, environmental and social impact of biogas projects are affected by decisions on technology, location and capacity, which are interdependent. The aim of this paper is to explore the mutual links between such decisions, and their impact on sustainability indicators at the light of Italian energy policies. Mixed integer linear programming is used to develop a biomass supply chain model to deal with strategic planning issues of biogas supply chains. The model is applied to a case study of a local community including 15 municipalities in Friuli Venezia Giulia, where a number of breeding, cropping and greenhouse farms could be involved in a joint biogas project or in the development of multiple, small scale initiatives. It is found that upgrading technologies become feasible under the new support mechanism, but optimal capacity and utilization paths are very sensitive to boundary conditions such as local feedstock and land availability
Effects of changes in Italian bioenergy promotion schemes for agricultural biogas projects: Insights from a regional optimization model
Full text linkItaly is a large producer of biogas from anaerobic digestion, which is mainly used for power generation with limited use of cogenerated heat. Other utilization pathways, such as biomethane injection into the natural gas grid or biomethane used as a vehicle fuel, remain unexplored. Given the dense grid of natural gas pipelines and existing Compressed Natural Gas (CNG) refueling stations in northern Italy, significant market opportunities for biogas could also arise in the heating and transport sectors. The main objectives of this paper are to explore the potential role of agricultural biogas in different utilization pathways. Biogas combustion for simultaneous production of heat and power in small Combined Heat and Power (CHP) facilities is also assessed, as is upgrading to biomethane for transport or natural gas grid injection in the specific context of northern Italy. The spatially explicit optimization model BeWhere is used to identify optimal locations where greenfield biogas plants could be installed and to determine the most economic and environmentally beneficial mix of conversion technologies and plant capacities. Carbon price, for instance in the form of tradable emission permits, is assessed as a policy instrument and compared with other options such as price premiums on biomethane or electricity costs. Results show that starting from a carbon price of 15 EUR/tCO(2), the cogeneration option is preferable if plants are located in the proximity of existing district heating infrastructure. CNG plants are only competitive starting at a carbon price of 70 EUR/tCO(2) in areas with high feedstock availability. The sensitivity analysis for energy prices reveals that a larger number of CNG facilities are included in the optimal mix at higher gas wholesale prices. This further indicates that specific premiums are needed to expand the biomethane market share, while greenhouse gas emission reductions would primarily be achieved by fostering cogeneration of electricity and heat supported by carbon price-based policy instruments
A Service Station Location Model to Explore Prospects and Policies for Alternative Transport Fuels: A Case of CNG Distribution in Italy
Full text linkCNG is an example of alternative gaseous fuel whose market development
requires supply infrastructure (pipelines), refuelling stations and alternative
vehicles to exist at the same time, which is known as the ‘‘chicken and egg
dilemma’’. In this chapter, a case study of limited or locally nonexistent market
development for CNG in an Italian frontier region is analyzed and a mixed integer
non linear programming model is introduced to evaluate the effect of incentive
measures envisaged by the regional government to foster refuelling station
development. It is found that, taking an entrepreneurs’ perspective of maximizing
profits, even with substantial capital grants investors are more likely to choose
higher demand areas, in spite of fiercer competition, rather than areas without
stations. Subsidies should be more specifically targeted to critical areas to be
efficient
Biomethane as transport fuel - A comparison with other biogas utilization pathways in northern Italy
No full textItaly is a large producer of biogas from anaerobic digestion, which is mainly used for power generation with limited use of cogenerated heat. Other utilization pathways, such as biomethane injection into the natural gas grid or biomethane used as a vehicle fuel, remain unexplored. Given the dense grid of natural gas pipelines and existing Compressed Natural Gas (CNG) refueling stations in northern Italy, significant market opportunities for biogas could also arise in the heating and transport sectors. The main objectives of this paper are to explore the potential role of agricultural biogas in different utiliztion pathways. Biogas combustion for simultaneous production of heat and power in small Combined Heat and Power (CHP) facilities is also assessed, as is upgrading to biomethane for transport or natural gas grid injection in the specific context of northern Italy. The spatially explicit optimization model BeWhere is used to identify optimal locations where greenfield biogas plants could be installed and to determine the most economic and environmentally beneficial mix of conversion technologies and plant capacities. Carbon price, for instance in the form of tradable emission permits, is assessed as a policy instrument and compared with other options such as price premiums on biomethane or electricity costs. Results show that starting from a carbon price of 15 EUR/tCO2, the cogeneration option is preferable if plants are located in the proximity of existing district heating infrastructure. CNG plants are only competitive starting at a carbon price of 70 EUR/tCO2 in areas with high feedstock availability. The sensitivity analysis for energy prices reveals that a larger number of CNG facilities are included in the optimal mix at higher gas wholesale prices. This further indicates that specific premiums are neeeded to expand the biomethane market share, while greenhouse gas emission reductions would primarily be achieved by fostering cogeneration of electricity and heat supported by carbon price-basd policy instruments
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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