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2.
PLoS One ; 13(6): e0199100, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29928039

RESUMO

In this paper, we investigate how crude oil price and volume traded affected the profitability of oil and gas companies in the United Kingdom (UK) since the financial crisis started in 2008. The study benefit from insights of the financial statements, to develop a model that focuses on how changes in oil price impact corporate performance. In order to observe the financial indicators that influence the performance, as well as the effects that changes in oil prices and demand of crude oil have on the profitability of oil and gas companies, we apply comparative regression analysis, including the generalised method of moments estimation technique for panel data set. The sample is consisting of 31 oil and gas companies in the UK, and the period analysed is 2006-2014. Results show that profitable oil and gas companies managed to face the drop in oil price and recover, characterized by significant cash flows and stock turnover, efficient use of assets, and high solvency rates. Although the oil price and volume traded do not significantly affect profitability and other financial ratios, if the oil price continues to decrease, it would permanently alter both the UK economy and oil and gas companies. In order to survive, companies make drastic cuts and defer essential investments, often at the long-term expense of asset performance. This study is important in a world where the energy consumption steadily grew over time. However, the renewable energy is cheaper and more environmentally friendly, and thus, countries where oil and gas industry is one of the most popular sectors face an economic decline. These results could be useful for investors, managers or decision makers, reclaiming strategic decisions in the current uncertain and volatile environment.


Assuntos
Comércio/economia , Indústria de Petróleo e Gás/economia , Petróleo/economia , Conservação de Recursos Energéticos/economia , Humanos , Energia Renovável/economia , Reino Unido
3.
J Environ Manage ; 129: 103-11, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23900083

RESUMO

Autotrophic microalgae represent a potential feedstock for transportation fuels, but life cycle assessment (LCA) studies based on laboratory-scale or theoretical data have shown mixed results. We attempt to bridge the gap between laboratory-scale and larger scale biodiesel production by using cultivation and harvesting data from a commercial algae producer with ∼1000 m(2) production area (the base case), and compare that with a hypothetical scaled up facility of 101,000 m(2) (the future case). Extraction and separation data are from Solution Recovery Services, Inc. Conversion and combustion data are from the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation Model (GREET). The LCA boundaries are defined as "pond-to-wheels". Environmental impacts are quantified as NER (energy in/energy out), global warming potential, photochemical oxidation potential, water depletion, particulate matter, and total NOx and SOx. The functional unit is 1 MJ of energy produced in a passenger car. Results for the base case and the future case show an NER of 33.4 and 1.37, respectively and GWP of 2.9 and 0.18 kg CO2-equivalent, respectively. In comparison, petroleum diesel and soy diesel show an NER of 0.18 and 0.80, respectively and GWP of 0.12 and 0.025, respectively. A critical feature in this work is the low algal productivity (3 g/m(2)/day) reported by the commercial producer, relative to the much higher productivities (20-30 g/m(2)/day) reported by other sources. Notable results include a sensitivity analysis showing that algae with an oil yield of 0.75 kg oil/kg dry biomass in the future case can bring the NER down to 0.64, more comparable with petroleum diesel and soy biodiesel. An important assumption in this work is that all processes are fully co-located and that no transport of intermediate or final products from processing stage to stage is required.


Assuntos
Biocombustíveis/análise , Conservação de Recursos Energéticos/métodos , Microalgas/química , Biomassa , Conservação de Recursos Energéticos/economia , Gasolina/análise , Israel , Modelos Teóricos , Petróleo/análise , Sensibilidade e Especificidade , Glycine max/química
5.
ChemSusChem ; 4(12): 1787-95, 2011 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-22105923

RESUMO

The multistep integration of hydrogen-selective membranes into catalytic partial oxidation (CPO) technology to convert natural gas into syngas and hydrogen is reported. An open architecture for the membrane reactor is presented, in which coupling of the reaction and hydrogen separation is achieved independently and the required feed conversion is reached through a set of three CPO reactors working at 750, 750 and 920 °C, compared to 1030 °C for conventional CPO technology. Obtaining the same feed conversion at milder operating conditions translates into less natural gas consumption (and CO(2) emissions) and a reduction of variable operative costs of around 10 %. It is also discussed how this energy-efficient process architecture, which is suited particularly to small-to-medium applications, may improve the sustainability of other endothermic, reversible reactions to form hydrogen.


Assuntos
Hidrogênio/química , Membranas Artificiais , Gás Natural , Óxido de Alumínio/química , Dióxido de Carbono/química , Monóxido de Carbono/química , Catálise , Conservação de Recursos Energéticos/economia , Custos e Análise de Custo , Temperatura Alta , Hidrogênio/economia , Oxirredução , Oxigênio/química , Oxigênio/economia , Paládio/química , Permeabilidade , Prata/química
6.
Ambio ; 39(3): 236-48, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20701180

RESUMO

Protecting the climate is not costly but profitable (even if avoided climate change is worth zero), mainly because saving fuel costs less than buying fuel. The two biggest opportunities, both sufficiently fast, are oil and electricity. The US, for example, can eliminate its oil use by the 2040s at an average cost of $15 per barrel ($2000), half by redoubled efficiency and half by alternative supplies, and can save three-fourths of its electricity more cheaply than operating a thermal power station. Integrative design permits this by making big energy savings cheaper than small ones, turning traditionally assumed diminishing returns into empirically observed expanding returns. Such efficiency choices accelerate climate-safe, inexhaustible, and resilient energy supply-notably the "micropower" now delivering about a sixth of the world's electricity and 90% of its new electricity. These cheap, fast, market-financeable, globally applicable options offer the most effective, yet most underestimated and overlooked, solutions for climate, proliferation, and poverty.


Assuntos
Clima , Carvão Mineral , Conservação de Recursos Energéticos , Fontes de Energia Elétrica , Petróleo , Política Pública , Automóveis/economia , Automóveis/normas , Carvão Mineral/economia , Conservação de Recursos Energéticos/economia , Conservação de Recursos Energéticos/métodos , Conservação de Recursos Energéticos/tendências , Fontes de Energia Elétrica/economia , Habitação/economia , Habitação/normas , Petróleo/economia
10.
Sci Eng Ethics ; 14(2): 177-200, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18075732

RESUMO

This paper approaches the choice between the open and closed nuclear fuel cycles as a matter of intergenerational justice, by revealing the value conflicts in the production of nuclear energy. The closed fuel cycle improve sustainability in terms of the supply certainty of uranium and involves less long-term radiological risks and proliferation concerns. However, it compromises short-term public health and safety and security, due to the separation of plutonium. The trade-offs in nuclear energy are reducible to a chief trade-off between the present and the future. To what extent should we take care of our produced nuclear waste and to what extent should we accept additional risks to the present generation, in order to diminish the exposure of future generation to those risks? The advocates of the open fuel cycle should explain why they are willing to transfer all the risks for a very long period of time (200,000 years) to future generations. In addition, supporters of the closed fuel cycle should underpin their acceptance of additional risks to the present generation and make the actual reduction of risk to the future plausible.


Assuntos
Conservação de Recursos Energéticos/métodos , Saúde Ambiental/ética , Relação entre Gerações , Resíduos Radioativos/ética , Eliminação de Resíduos , Justiça Social/ética , Atitude Frente a Saúde , Comportamento de Escolha/ética , Conflito Psicológico , Conservação de Recursos Energéticos/economia , Conservação de Recursos Energéticos/tendências , Análise Custo-Benefício , Saúde Ambiental/organização & administração , Previsões , Conhecimentos, Atitudes e Prática em Saúde , Direitos Humanos , Humanos , Plutônio/efeitos adversos , Saúde Pública/ética , Proteção Radiológica/economia , Proteção Radiológica/métodos , Resíduos Radioativos/efeitos adversos , Resíduos Radioativos/economia , Resíduos Radioativos/prevenção & controle , Radioatividade , Eliminação de Resíduos/economia , Eliminação de Resíduos/ética , Eliminação de Resíduos/métodos , Comportamento de Redução do Risco , Gestão da Segurança/ética , Gestão da Segurança/organização & administração , Justiça Social/economia , Justiça Social/psicologia , Justiça Social/tendências , Responsabilidade Social , Valores Sociais , Urânio/efeitos adversos
11.
J Air Waste Manag Assoc ; 57(8): 919-33, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17824282

RESUMO

We examined life cycle environmental and economic implications of two near-term scenarios for converting cellulosic biomass to energy, generating electricity from cofiring biomass in existing coal power plants, and producing ethanol from biomass in stand-alone facilities in Ontario, Canada. The study inventories near-term biomass supply in the province, quantifies environmental metrics associated with the use of agricultural residues for producing electricity and ethanol, determines the incremental costs of switching from fossil fuels to biomass, and compares the cost-effectiveness of greenhouse gas (GHG) and air pollutant emissions abatement achieved through the use of the bioenergy. Implementing a biomass cofiring rate of 10% in existing coal-fired power plants would reduce annual GHG emissions by 2.3 million metric tons (t) of CO2 equivalent (7% of the province's coal power plant emissions). The substitution of gasoline with ethanol/gasoline blends would reduce annual provincial lightduty vehicle fleet emissions between 1.3 and 2.5 million t of CO2 equivalent (3.5-7% of fleet emissions). If biomass sources other than agricultural residues were used, additional emissions reductions could be realized. At current crude oil prices ($70/barrel) and levels of technology development of the bioenergy alternatives, the biomass electricity cofiring scenario analyzed is more cost-effective for mitigating GHG emissions ($22/t of CO2 equivalent for a 10% cofiring rate) than the stand-alone ethanol production scenario ($92/t of CO2 equivalent). The economics of biomass cofiring benefits from existing capital, whereas the cellulosic ethanol scenario does not. Notwithstanding this result, there are several factors that increase the attractiveness of ethanol. These include uncertainty in crude oil prices, potential for marked improvements in cellulosic ethanol technology and economics, the province's commitment to 5% ethanol content in gasoline, the possibility of ethanol production benefiting from existing capital, and there being few alternatives for moderate-to-large-scale GHG emissions reductions in the transportation sector.


Assuntos
Poluição do Ar/prevenção & controle , Celulose/química , Celulose/economia , Fontes Geradoras de Energia/economia , Etanol/economia , Etanol/isolamento & purificação , Biomassa , Carvão Mineral , Conservação de Recursos Energéticos/economia , Conservação de Recursos Energéticos/métodos , Análise Custo-Benefício , Eletricidade , Etanol/química , Ontário , Petróleo/economia , Centrais Elétricas/economia
15.
Environ Sci Technol ; 41(23): 7967-73, 2007 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-18186324

RESUMO

This study presents a consistent, national-level evaluation of potential biodiesel volumes and prices, replicated across 226 countries, territories, and protectorates. Utilizing all commercially exported lipid feedstocks from existing agricultural lands, we compare the upper-limit potential for expanded biodiesel production in terms of absolute biodiesel volumes, profitable potential from biodiesel exports, and potential from expanded vegetable oil production through agricultural yield increases. Country findings are compared across a variety of economic, energy, and environmental metrics. Our results show an upper-limit worldwide volume potential of 51 billion liters from 119 countries; 47 billion of which could be produced profitably at today's import prices. Also significant production gains are possible through increasing agricultural yields: a 12-fold increase over existing potential, primarily hinging on better management of tropical oilseed varietals.


Assuntos
Conservação de Recursos Energéticos/economia , Fontes Geradoras de Energia/economia , Biotecnologia/métodos , Conservação de Recursos Energéticos/métodos , Ecossistema , Humanos , Óleos de Plantas/química , Formulação de Políticas
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