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1.
The challenges in developing technology for the capture and storage of CO2 from coal, oil and gas power generation, as well as those associated with the storage of nuclear waste, are widely regarded as solvable. According to proponents of clean coal, oil and gas technologies, as well as the proponents of nuclear technology, it is only a matter of time and resources to find a solution to their waste problems. Similarly, the Australian Government argues that our main efforts need to be concentrated on clean coal technologies, as well as considering the nuclear option. However, when it comes to the challenges associated with renewable energy technologies, like intermittency of wind generated grid power, storage of electricity from renewable energy and so on, there seems to be an attitude amongst Australian energy planners that these challenges represent insurmountable technical and financial problems, and will, at least in the short to medium term, prevent them from becoming a viable alternative to coal, oil, gas and uranium based energy technologies.  相似文献   

2.
Various types of energy sources are used in the residential and industrial sectors. Choosing the type of sources is important. When an energy source is selected, its CO2 equivalent and energy and exergy prices must be known for a sustainable future and for establishing energy policies. These prices are based on their energy values. Exergy analysis has been recently applied to a wide range of energy-related systems. Thus, obtaining the exergy values has become more meaningful for long-term planning. In this study, energy and exergy prices of various energy sources along with CO2 equivalents are calculated and compared for residential and industrial applications in Turkey. Energy sources considered include coal, diesel oil, electricity, fuel oil, liquid petroleum gas (LPG), natural gas, heat pumps and geothermal, and their prices were obtained over a period of 18 months, from January 2008 to June 2009. For the residential and industrial sectors, minimum energy and exergy prices were found for ground source heat pumps, while maximum energy and exergy prices belong to LPG for both sectors.  相似文献   

3.
By employing historical case study methodology, this paper examines the transition towards renewable energy and increased energy efficiency in the Swedish pulp and paper industry (PPI) during the 1970s and 1980s. Between 1973 and 1990, CO2 emissions were cut by 80 % in this sector, and this was mainly achieved by substituting away from oil to biofuels in the form of by-products from the pulp manufacturing process. The CO2 reduction was also a result of energy efficiency improvements and increased internal production of electricity through back-pressure turbine power generation. Sweden was highly dependent on oil at the advent of the first Oil Crisis in 1973, and the increased oil prices put pressure on the Swedish government and the energy-intensive PPI to reduce this oil dependency. Of central importance for the energy transition was the highly collaborative strategy of the PPI, both internally among pulp mills as well as between the sector as a whole and the corporatist Swedish state administration. The Swedish government chose a proactive strategy by emphasizing knowledge management and collaboration with the industry along with the substitution of internal biofuels for oil. The transition was also characterized by a strong focus on unutilized potentials in the PPI; a previous waste problem now could be transformed into energy savings and improved energy efficiency. Energy taxes and fees also played an important role in Swedish energy policy during the 1970s and the 1980s. All in all, the study illustrates the central role of governments and their ability to push industrial sectors into new technological pathways through a wide palette of mutually reinforcing policy instruments. The results further point at the importance of a more holistic understanding of the interplay between different policies and their impacts in the longer run.  相似文献   

4.
In China, most energy prices are controlled by the government and are under-priced, which means energy subsidies existing. Reforming energy subsidies have important implications for sustainable development through their effects on energy price, energy use and CO2 emission. This paper applies a price-gap approach to estimate China's fossil-fuel related subsidies with the consideration of the external cost. Results indicate that the magnitude of subsidies amounted to CNY 1214.24 billion in 2008, equivalent to 4.04% of GDP of that year. Subsidies for oil products are the largest, followed by subsidies for the coal and electricity. Furthermore, an input–output model is used to analyze the impacts of energy subsidies reform on different industries and general price indexes. The findings show that removal of energy subsidies will have significant impact on energy-intensive industry, and consequently push up the general price level, yet with a small variation. Removing oil products subsidies will have the largest impact, followed by electricity, coal and natural gas. However, no matter which energy price increases, PPI is always the most affected, then GDP deflator, with CPI being the least. Corresponding compensation measures should be accordingly designed to offset the negative impact caused by energy subsidies reform.  相似文献   

5.
Hydrothermal liquefaction (HTL) is a promising technology that involves converting biomass into a liquid energy carrier called bio‐oil in sub/supercritical water. The unique physico‐chemical properties of bio‐oil, particularly its remarkably high energy density, renewability, and sustainability, can address current global environmental challenges and energy crisis. This review assesses the influence of operating parameters, including biomass type, reaction temperature, holding time, biomass/H2O ratio, heating rate, pressure, and atmosphere, and catalysis, on the yield and quality of bio‐oil. The existing problems in HTL are also analyzed, and its further development is explored. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

6.

Numerous studies indicated that oil sources in the world will come to an end. As a result, new alternative energy sources will be required to substitute for oil. Some of the experimental studies showed that vegetable oil can be used as alternative fuel in diesel engines. The viscosity of vegetable oil is much higher than that of standard diesel fuel; therefore, the high viscosity of the vegetable oil can cause problems for injection systems and engine components. To decrease viscosity, cottonseed methyl ester was obtained from raw cottonseed oil by transesterification method. In this study, cottonseed methyl ester was used in a four-stroke, single cylinder, and air-cooled diesel engine as alternative fuel. Engine tests carried out at full load-different speed range, the engine torque and power of cottonseed oil methyl ester was found to be lower than that of diesel fuel in the range of 3–9% and specific fuel consumption was higher than that of diesel fuel by approximately 8–10%. CO 2 , CO, and NO x emissions of cottonseed methyl ester were lower than that of diesel fuel.  相似文献   

7.
This paper tests for the short and long-run relationship between economic growth, carbon dioxide (CO2) emissions and energy consumption, using the Environmental Kuznets Curve (EKC) by employing both the aggregated and disaggregated energy consumption data in Malaysia for the period 1980–2009. The Autoregressive Distributed Lag (ARDL) methodology and Johansen–Juselius maximum likelihood approach were used to test the cointegration relationship; and the Granger causality test, based on the vector error correction model (VECM), to test for causality. The study does not support an inverted U-shaped relationship (EKC) when aggregated energy consumption data was used. When data was disaggregated based on different energy sources such as oil, coal, gas and electricity, the study does show evidences of the EKC hypothesis. The long-run Granger causality test shows that there is bi-directional causality between economic growth and CO2 emissions, with coal, gas, electricity and oil consumption. This suggests that decreasing energy consumption such as coal, gas, electricity and oil appears to be an effective way to control CO2 emissions but simultaneously will hinder economic growth. Thus suitable policies related to the efficient consumption of energy resources and consumption of renewable sources are required.  相似文献   

8.
In recent years, oil resources are becoming exhausted making their exorbitant prices. In addition to the depletion rate of pollution reaches alarming levels. Because of these facts and in order to diminish the fatality of those problems, the automotive technology provided by Cem electric energy that is treated as a non-polluting energy is considered as a solution. In this paper, we propose a configuration of a 4WD vehicle (Four Wheel Drive) with two asynchronous motors can be ordered by the technique of Direct Torque Control. The vehicle can operate in single front wheel (wheel), which means that the engine torque requested develops only in the case of the 4WD torque is developed by two motor (I and II). An implementation of the algorithm is performed in our laboratory on two identical motors with a variable set point torque which directly reflects the variation of the speed imposed by the driver.  相似文献   

9.
Peak oil research and the Association for the Study of Peak Oil and Gas (ASPO) have contributed a great deal to improve people's recognition of peak oil. Although peak oil is becoming a part of public recognition, it is still hard to say whether peak oil discussion will develop into a theory such as “peakoilism”. On one hand, there are still some difficult problems in peak oil research. On the other hand, the peakoilers have the potential for scientific research and have their allies: the climate change researchers and the new energy advocates. Oil is a limited, non-renewable resource, and an oil peak is inevitable. Peak oil theory is a kind of development theory rather than a crisis theory, which promotes reasonable utilization of the limited oil resources, promotes conservation, and encourages the development of renewable energy.  相似文献   

10.
In this paper an energy balance and a greenhouse gas profile has been formulated for the county of Wexford, situated in the south east of Ireland. The energy balance aims to aggregate all energy consumption in the county for the year 2006 across the following sectors; residential, agriculture, commerce and industry, and transport. The results of the energy balance are compared with the previous energy balance of 2001 where it is found that the residential sector is the biggest emitter of CO2 with 38% of total emissions with the transport and industry/commerce sectors sharing second place on 28%. Consumption of oil is seen to have increased significantly in nearly all sectors, accounting for over 70% of the total final energy consumed (TFC) while the total primary energy requirement (TPER) sees oil consumption accounting for 91% of all fuels consumed. To take into account the contribution of agriculture in total GHG emissions the gases CH4 and N2O will be estimated from the agricultural and waste sectors. The results show that methane contributes 25% of total GHG emissions with agriculture being the primary contributor accounting for 36% of total emissions.  相似文献   

11.
Biofuel production from algae feedstock has become a topic of interest in the recent decades since algae biomass cultivation is feasible in aquaculture and does therefore not compete with use of arable land. In the present work, hydrothermal liquefaction of both microalgae and macroalgae is evaluated for biofuel production and compared with transesterifying lipids extracted from microalgae as a benchmark process. The focus of the evaluation is on both the energy and carbon footprint performance of the processes. In addition, integration of the processes with an oil refinery has been assessed with regard to heat and material integration. It is shown that there are several potential benefits of co-locating an algae-based biorefinery at an oil refinery site and that the use of macroalgae as feedstock is more beneficial than the use of microalgae from a system energy performance perspective. Macroalgae-based hydrothermal liquefaction achieves the highest system energy efficiency of 38.6%, but has the lowest yield of liquid fuel (22.5 MJ per 100 MJalgae) with a substantial amount of solid biochar produced (28.0 MJ per 100 MJalgae). Microalgae-based hydrothermal liquefaction achieves the highest liquid biofuel yield (54.1 MJ per 100 MJalgae), achieving a system efficiency of 30.6%. Macro-algae-based hydrothermal liquefaction achieves the highest CO2 reduction potential, leading to savings of 24.5 resp 92 kt CO2eq/year for the two future energy market scenarios considered, assuming a constant feedstock supply rate of 100 MW algae, generating 184.5, 177.1 and 229.6 GWhbiochar/year, respectively. Heat integration with the oil refinery is only possible to a limited extent for the hydrothermal liquefaction process routes, whereas the lipid extraction process can benefit to a larger extent from heat integration due to the lower temperature level of the process heat demand.  相似文献   

12.
A rapidly building concensus, in the rich developed nations, is that less develped countries (LDC) should support large, costly, programmes of rapidly developing non-oil renewable energy sources, and energy conservation. However, oil use in the LDCs is tiny in relation to that of rich nations, even if growing faster. On a per capita base the difference is greater still. Thus conservation, as a solution to short run oil supply problems (e.g. OPEC output ceilings) is a responsibility of the nation grouping that uses and wastes most oil. Small percentage cuts by the OECD-IEA group could provide ample supplies for the growing needs of LDCs without driving prices inevitably higher. For LDCs there are now many devices for controlling or reducing their foreign exhange spending on oil per unit import. Accelerated oil search and devlopment provides the best midterm opportunities for solving oil supply problems in LDCs especially if OPEC and rich nation loan funding and technical support are accelerated. the impetus for the necessarily costly rapid development of unconventional energy sources must and should come from the rich nation in the short and midterm, for aid-assisted transfer to LDSs in the longer term. This will allow the scarce capital of LDCs to be utilized for non-energy sectors where needs are immediate and cirticial, and for oil search and development.  相似文献   

13.
It is important to evaluate impacts of fossil fuel price hikes and climate stabilization that force the global energy system to adopt alternative and efficient technologies by routing future energy system dynamics into a different technology roadmap. Hence, a high-regional-resolution and technology-rich DNE21+ model is used for the simulation of some price-hike scenarios for the period from 2000 to 2030 by increasing the ordinate of cost–potential curve of crude oil, natural gas and coal by 55 US$(00)/bbl, 3.8 US$(00)/kcf and 56 US$(00)/tonne, respectively, above their reference values; and 550 ppmv stabilization is implemented by carbon limitation from 6998 to 8250 MtC/yr. This study detected that hike in fossil fuel prices acts as an anti-catalyst for human-induced anthropogenic emissions and alleviates heavy dependency upon fossil fuels. Further, it partially solves problems of climate change by reducing CO2 emission levels (23%), reflects human behavior through energy conservation (1.4 Gtoe), calls for efficiency improvement (7%), adopts more efficient and alternative technologies, compared to reference; however, with 550 ppmv stabilization, energy conservation rises to 1.6 Gtoe, demands 16% higher efficiency improvement and reduces CO2 emission by 36%, relative to reference.  相似文献   

14.
The province of Alberta faces the challenge of balancing its commitment to reduce CO2 emissions and the growth of its energy-intensive oil sands industry. Currently, these operations rely on the Alberta electricity system and on-site generation to satisfy their steam and electricity requirements. Most of the on-site generation units produce steam and electricity through the process of cogeneration. It is unclear to what extent new and existing operations will continue to develop cogeneration units or rely on electricity from the Alberta grid to meet their energy requirements in the near future. This study explores the potential for reductions in fuel usage and CO2 emissions by increasing the penetration of oil sands cogeneration in the provincial generation mixture. EnergyPLAN is used to perform scenario analyses on Alberta’s electricity system in 2030 with a focus on transmission conditions to the oil sands region. The results show that up to 15–24% of CO2 reductions prescribed by the 2008 Alberta Climate Strategy are possible. Furthermore, the policy implications of these scenarios within a deregulated market are discussed.  相似文献   

15.
There is a large potential to reduce primary energy use and CO2 emissions from the Swedish building stock. Here detached houses heated by oil, natural gas or electric boilers were assessed. CO2 emissions, primary energy use and heating costs were evaluated before and after implementing house envelope measures, conversions to more efficient heating systems and changes to biomass fuel use. The study included full energy chains, from natural resources to usable heat in the houses. The aim was to evaluate the societal economic cost effectiveness of reducing CO2 emission and primary energy use by different combinations of changes. The results demonstrated that for a house using an electric boiler, a conversion to a heat pump combined with house envelope measures could be cost efficient from a societal economic perspective. If the electricity was based on biomass, the primary energy use was at the same time reduced by 70% and the CO2 emission by 97%. Large emission reductions were also seen for conversions from oil and gas boilers to a biomass-based system. However, for these conversions the heating cost increased, leading to a mitigation cost of around €50/tonne C avoided. The price of oil and natural gas greatly influenced the competitiveness of the alternatives. House envelope measures were more cost-effective for houses with electric boilers as the cost of energy for this system is high. The results are specific to a Swedish context, but also give an indication of the potential in other regions, such as northern European and large parts of North America, which have both a cold climate and a widespread use of domestic boilers.  相似文献   

16.
This is a study of world energy resource sustainability within the context of resource peak production dates, advanced energy use technologies in the transportation and electricity generation energy use sectors, and alternative fuel production including hydrogen. The finding causing the most concern is the projection of a peak in global conventional oil production between now and 2023. In addition, the findings indicate that the peak production date for natural gas, coal, and uranium could occur by 2050. The central question is whether oil production from non-conventional oil resources can be increased at a fast enough rate to offset declines in conventional oil production. The development of non-conventional oil production raises concerns about increased energy use, greenhouse gas emissions, and water issues. Due to the emerging fossil fuel resource constraints in coming decades, this study concludes that it is prudent to begin the development of hydrogen production and distribution systems in the near-term. The hydrogen gas is to be initially used by fuel cell vehicles, which will eliminate tailpipe greenhouse gas emissions. With a lowering of H2 production costs through the amortization of system components, H2 can be an economic fuel source for electricity generation post-2040.  相似文献   

17.
China now faces the three hard truths of thirsting for more oil, relying heavily on coal, and ranking first in global carbon dioxide (CO2) emissions. Given these truths, two key questions must be addressed to develop a low-carbon economy: how to use coal in a carbon-constrained future? How to increase domestic oil supply to enhance energy security? Carbon Capture and Storage (CCS) may be a technological solution that can deal with today's energy and environmental needs while enabling China to move closer to a low-carbon energy future. This paper has been developed to propose a possible CCS roadmap for China. To develop the roadmap, we first explore major carbon capture opportunities in China and then identify critical CCS-enabling technologies, as well as analyze their current status and future prospects. We find that coal gasification or polygeneration in combination with CCS could be a nearly unbeatable combination for China's low-carbon future. Even without CCS, gasification offers many benefits: once coal is gasified into syngas, it can be used for many different purposes including for alternative fuels production, thereby increasing the domestic oil supply and the flexibility of the energy system.  相似文献   

18.
This study presents an assessment of the energy security of Thailand using nineteen indicators. The assessment period is for a 45 year period (1986–2030), and used published data for 1986–2009, and applying three energy scenarios for the period 2010–2030. The three scenarios considered were “high economic growth and least cost option (HEG&LC)”, “low carbon society (LCS)”, and “current policy (CP)”. The results show that LCS scenario shows higher energy security or lower vulnerability to energy risk on a long term. However, to achieve this, the additional target of energy saving by 2030 should be changed from 25% reduction of energy intensity of final energy consumption to 60% energy intensity reduction of primary energy compared to 2009 level. One benefit would be an increase in the non-carbon incentive fuel portfolio by 33% of total primary energy supply in 2030. A reduction in crude oil and natural gas domestic production will be offset by an increase in their imports. CO2 emission reduction of 123 MtCO2 and improvements in domestic energy reserves will also result.  相似文献   

19.
One of the key factors affecting the economic viability and safe deployment of wood pellet fired systems on a large scale is wood pellet stability. Wood pellets are extremely moisture unstable and present significant problems during the transportation, storage and handling stages of their lifetime. This study proposes an approach for creating moisture stable wood pellets through the addition of hydrophobic coatings. Pellets were treated with paraffin oil, castor oil, mineral oil and linseed oil and submerged in water for up to 1800 s. The strength of untreated pellets was found to decrease by around 94% after being submerged for 60 s, whereas no appreciable reduction in pellet strength was recorded after 1800 s in all of the oil treated cases. Treatment with oil was also found to reduce the formation of airborne fines and increase the energy density of wood pellets, increasing their HHV by up to 1.2 MJ kg−1.  相似文献   

20.
Portugal is a country with an energy system highly dependent on oil and gas imports. Imports of oil and gas accounted for 85% of the country’s requirements in 2005 and 86% in 2006. Meanwhile, the share of renewable energy sources (RES) in the total primary energy consumption was only 14% in 2006. When focusing only on electricity production, the situation is somewhat better. The share of RES in gross electricity production varies between 20% and 35% and is dependent on the hydropower production in wet and dry years. This paper presents, on a national scale, Portugal’s energy system planning and technical solutions for achieving 100% RES electricity production. Planning was based on hourly energy balance and use of H2RES software. The H2RES model provides the ability to integrate various types of storages into energy systems in order to increase penetration of the intermittent renewable energy sources or to achieve a 100% renewable island, region or country. The paper also represents a stepping-stone for studies offering wider possibilities in matching and satisfying electricity supply in Portugal with potential renewable energy sources. Special attention has been given to intermittent sources such as wind, solar and ocean waves that can be coupled to appropriate energy storage systems charged with surplus amounts of produced electricity. The storage systems also decrease installed power requirements for generating units. Consequently, these storages will assist in avoiding unnecessary rejection of renewable potential and reaching a sufficient security of energy supply.  相似文献   

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