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A new fully predictive method was developed to calculate the risk of asphaltene precipitation in oil reservoirs based on a modification of the Asphaltene Instability Trend (ASIST) method. For prediction of asphaltene precipitation by oil depletion, this new method simplifies the ASIST method in order to use a minimum number of experimental data. As a novelty, prediction of asphaltene precipitation by CO2 displacement using a modification of the ASIST method is introduced. Both modifications were validated for a large number of oils from the literature. Results show that with both modifications this new method provides better results than previous ones to predict the risk of asphaltene precipitation in oils by depletion and unprecedented good results to evaluate potential asphaltene precipitation in oil reservoirs due to CO2 displacement with requirement of few experimental data. The proposed method may be used in the oil and gas industry to predict the risk of asphaltene precipitation by depletion or by CO2 displacement.

Because of concerns about global climate change, possible global oil depletion, and because of potential benefits for both urban air pollution and rural employment and industry, many countries both in and out of the Organization for Economic Cooperation and Development (OECD), are promoting liquid biofuels as a replacement for oil-based transport fuels, and global output is rising steadily. In fact, bioenergy use in general is promoted, and is expected to play a major role in climate change mitigation. But bioenergy use in general faces competition for resources such as land, water and fertiliser from the two other general biomass uses, food production and biomaterials. Ethically, food production should take precedence over the other two uses (and at present all bioliquids are made from foodstuffs), and using biomass for biomaterials will in many situations reduce greenhouse gas emissions more than using the same amount of biomass for energy. Where a given amount of biomass is available for transport energy use, it will usually produce more greenhouse gas reductions per vehicle-km if used to produce electricity rather than liquid biofuels. Finally, there is signs that internal combustion engine vehicles could be phased out in the coming decades. If so, liquid biofuels will be phased out along with existing oil-based transport fuels. In conclusion, except for specialist uses, liquid biofuels do not appear to have a long-term future.

20 years ago, in 1998, Scientific American published a paper by Colin J. Campbell and Jean H. Laherrere titled “The End of Cheap Oil” [1], starting a debate on oil depletion continuing to the present day. It was the return of a viewpoint on oil depletion which had been proposed more than 40 years before by Marion King Hubbert [2]⁠ and, in later years, largely forgotten. In their paper, Campbell and Laherrere updated Hubbert’s model with new reserve estimates and proposed that the world’s crude oil production would peak around 2004–2005, and then start an irreversible decline. Shortly afterward, Colin Campbell proposed the term “peak oil” for the highest global oil production level. The term was to become popular over the following decade, generating a true movement of ideas sometimes called the “peak oil movement.” Today, these predictions turn out to have been only partially correct, mainly because the role of “non-conventional” oil was underestimated. The peak oil movement seems to have faded away, while the concept seems to have disappeared from the debate and to be commonly described has having been “wrong.” The present paper reviews the cycle of the peak oil movement, examining how the peak oil concept was understood with the public and the decision makers and what caused its diffusion and its demise, at least up to the present time.

Renewable energy, such as hydro power, photovoltaics and wind turbines, has become the most widely applied solutions for addressing issues associated with oil depletion, increasing energy demand and anthropogenic global warming. Solar and wind energy are strongly dependent on weather resources with intermittent and fluctuating features. To filter these variabilities, battery energy storage systems have been broadly accepted as one of the potential solutions, with advantages such as fast response capability, sustained power delivery, and geographical independence. During the implementation of battery energy storage systems, one of the most crucial issues is to optimally determine the size of the battery for balancing the trade-off between the technical improvements brought by the battery and the additional overall cost. Numerous studies have been performed to optimise battery sizing for different renewable energy systems using a range of criteria and methods. This paper provides a comprehensive review of battery sizing criteria, methods and its applications in various renewable energy systems. The applications for storage systems have been categorised based on the specific renewable energy system that the battery storage will be a part. This is in contrast to previous studies where the battery sizing approaches were either arranged as an optimised component in renewable systems or only accounted for one category of renewable system. By taking this approach, it becomes clear that the critical metrics for battery sizing, and by extension the most suitable method for determining battery size, are determined by the type of renewable energy system application, as well as its size. This has important implications for the design process as the renewable energy system application will drive the battery energy storage system sizing methodology chosen.

As concerns of oil depletion and security of supply remain as severe as ever, and faced with the consequences of climate change due to greenhouse gas emissions, Europe is increasingly looking at alternatives to traditional road transport technologies. Battery Electric Vehicles (BEVs) are seen as a promising technology, which could lead to the decarbonisation of the Light Duty Vehicle fleet and to independence from oil. However it still has to overcome some significant barriers to gain social acceptance and obtain appreciable market penetration. This review evaluates the technological readiness of the different elements of BEV technology and highlights those technological areas where important progress is expected. Techno-economic issues linked with the development of BEVs are investigated. Current BEVs in the market need to be more competitive than other low carbon vehicles, a requirement which stimulates the necessity for new business models. Finally, the all-important role of politics in this development is, also, discussed. As the benefit of BEVs can help countries meet their environmental targets, governments have included them in their roadmaps and have developed incentives to help them penetrate the market.

In the late 50s a debate on the Oil depletion has been started which is continuing to the present day. Campbell largely updated Hubert's model with new reserve resources forecast and estimated that the world's oil production would peak around the 2004–2006 and then would decline over the years. Then was Campbell who proposed the term which was later widely used as the “The peak Oil” to define the global maximum of the Oil production Time series. In this paper a scenario planning based on the expert-choices (participated by the OPEC experts and policy makers) combined with the Hubert's forecast method (based on the Monte-Carlo non-linear forecast Regression) is done for the peak-oil forecasting and three high score scenarios have been derived. The “True me”, the “feigned sleep” and the death of the unity in which these scenarios are highly affected by the political environments of each. However, in one of the scenarios because of the tensions in the political environment the peak oil will not occur by 2040 but the other scenarios show that peak oil maybe is sooner than the world expects (the mid-2020s) and energy supply and demand markets must be ready for this phenomena.

The use of multi-fractured horizontal wells has helped to develop tight oil reservoirs, but, if oil depletion occurs, the estimated ultimate recovery is low. Water flooding can be regarded as an easily applied method for improving oil recovery. This study aimed to optimize the scale of the stimulated reservoir volume (SRV) by conducting an experiment to verify the water injection capacity of the Chang 7 Formation, which is situated within in a typical tight oilfield. A one-dimensional long core displacement experiment was designed based on injecting formation water into a tight matrix core and fractured cores with different fracture lengths. Results were then verified and analyzed using core flood simulation and targeted field tests, and they clarified the feasibility of injecting water into a tight oil formation when the injection well is fractured, or when fractures exist near the injection well. It was also verified that although fractures increase the equivalent permeability in the fractured core and promote pressure propagation, they can also lead to rapid water breakthrough if they communicate with the producer well. It is thus considered that optimization of the SRV extent would enhance the recovery of oil and decrease the risk of water breakthrough.

Rapacious fossil fuel extraction occurs if fossil fuel producers fear that there is a probability that their under-the-ground assets becomes worth less. They show that rapacious depletion of oil reserves occurs if there is a probability of a breakthrough renewable energy coming to the market or a probability of climate policy finally becoming seriously ambitious. These are examples of one-way regime switches leading to the so-called Green Paradox. Two-way regimes switches also lead to rapacious oil depletion. They occur if there is a chance of being removed from office in a partisan political context with perennial election cycles or if there are dynamic resource wars with the hazard of being removed from office dependent on fighting efforts. This rapacity effect is stronger in societies with bad institutions and lack of political cohesiveness.

Despite an increase of oil production from unconventional resources, concerns about the depletion of ‘cheap oil’ are more imminent than ever. Recognising the importance of media in influencing public opinion, risk perceptions and policy making, this research presents a framing analysis of peak oil in The Economist s’ news magazine (2008 and 2012). One hundred and seventy articles, of which 58 focused on energy security and oil production, were analysed using content and discourse analysis. Coverage was multi-facetted, and included oil depletion as one storyline within the supply challenge frame, especially during times of very high oil prices. Oil prices and the rapid growth in ‘fracking’ were found to be critical discourse moments, influencing the nature of oil coverage in The Economist . Overall, due to The Economist 's neoliberal ideology and the resulting optimistic framing of market forces and new technologies, this research found that the news magazine does not contribute majorly to enhancing the public debate on peak oil.

Ireland imports 88% of its energy requirements. Oil makes up 59% of total final energy consumption (TFC). Import dependency, low fuel diversity and volatile prices leave Ireland vulnerable in terms of energy security. This work models energy security scenarios for Ireland using long term macroeconomic forecasts to 2050, with oil production and price scenarios from the International Monetary Fund, within the Irish TIMES energy systems model. The analysis focuses on developing a least cost optimum energy system for Ireland under scenarios of constrained oil supply (0.8% annual import growth, and –2% annual import decline) and subsequent sustained long term price shocks to oil and gas imports. The results point to gas becoming the dominant fuel source for Ireland, at 54% total final energy consumption in 2020, supplanting oil from reference projections of 57% to 10.8% TFC. In 2012, the cost of net oil imports stood at €3.6 billion (2.26% GDP). The modelled high oil and gas price scenarios show an additional annual cost in comparison to a reference of between €2.9bn and €7.5bn by 2020 (1.9–4.9% of GDP) to choose to develop a least cost energy system. Investment and ramifications for energy security are discussed.

Decarbonising transport is proving to be one of today's major challenges for the global automotive industry due to many factors such as the increase in greenhouse gas and particulate emissions affecting not only the climate but also humans, the increase in pollution, rapid oil depletion, issues with energy security and dependency from foreign sources and population growth. For more than a century, our society has been dependent upon oil, and major breakthroughs in low- and ultra-low carbon technologies and vehicles are urgently required. This review paper highlights the current status of hybrid, battery and fuel cell electric vehicles from an electrochemical and market point of view. The review paper also discusses the advantages and disadvantages of using each technology in the automotive industry and the impact of these technologies on consumers.

We build a theoretical framework that allows for endogenous conflict behaviour (i.e., fighting efforts) and for endogenous natural resource exploitation (i.e., speed, ownership, and investments). While depletion is spread in a balanced Hotelling fashion during peace, the presence of conflict creates incentives for rapacious extraction, as this lowers the stakes of future contest. This voracious extraction depresses total oil revenue, especially if world oil demand is relatively elastic and the government’s weapon advantage is weak. Some of these political distortions can be overcome by bribing rebels or by government investment in weapons. The shadow of conflict can also make less efficient nationalized oil extraction more attractive than private extraction, as insecure property rights create a holdup problem for the private firm and lead to a lower license fee. Furthermore, the government fights less intensely than the rebels under private exploitation, which leads to more government turnover. Without credible commitment to future fighting efforts, private oil depletion is only lucrative if the government’s non-oil office rents are large and weaponry powerful, which guarantees the government a stronger grip on office and makes the holdup problem less severe.

Taking into account oil depletion, increasing population, and increasing energy demand, electrical power generation has entered into a new phase of evolution, which can be characterized mainly by increasing concerns about climate change, by a transition from a hydrocarbon-based economy, and by an efficient utilization of energy. In this sense, it seems that alternative energies have gathered considerable momentum since 1970s oil crisis. Moreover, Earth seems to have enough power to cover World’s electrical power demand but not by a single source; for this reason, recent researches have been carried out in order to design in an optimal way system’s configuration. Nevertheless, because of the randomized nature of alternative energy sources, electrical load profile, as well as the non-linear response of system components, to mention a few, is not an easy to assess the hybrid energy system performance; therefore, hybrid energy system designing has been a complex task. For this reason, the aim of this paper is to present a brief review about the sizing methodologies developed in the recent years.

This review paper summarises and evaluates the evidence regarding four issues that are considered to be of critical importance for future global oil supply. These are: a) how regional and global oil resources are distributed between different sizes of field; b) why estimates of the recoverable resources from individual fields tend to grow over time and the current and likely future contribution of this to global reserve additions; c) how rapidly the production from different categories of field is declining and how this may be expected to change in the future; and d) how rapidly the remaining recoverable resources in a field or region can be produced. It is shown that, despite serious data limitations, the level of knowledge of each of these issues has improved considerably over the past decade. While the evidence on reserve growth appears relatively encouraging for future global oil supply, that on decline and depletion rates does not. Projections of future global oil supply that use assumptions inconsistent with this evidence base are likely to be in error.

This paper focuses on medium term policy options in the economic context of natural resource depletion. In particular, a novel approach for analyzing the impact of the permanent income hypothesis (PIH) with a dynamic recursive computable general equilibrium (CGE) model is employed. The model is benchmarked in an oil producing country with declining production, namely Cameroon. The results show that the PIH renders public finances less vulnerable during the post-oil transition. However, adopting the PIH is not associated with substantial improvements in growth and household welfare in Cameroon. Therefore, the PIH cannot be the only basis for better management of oil revenues in the country.

An agent-based computational laboratory for exploratory energy policy by means of controlled computational experiments is proposed. It is termed the ACEGES (agent-based computational economics of the global energy system). In particular, it is shown how agent-based modelling and simulation can be applied to understand better the challenging outlook for oil production by accounting for uncertainties in resource estimates, demand growth, production growth and peak/decline point. The approach emphasises the idea that the oil system is better modelled not as black-box abode of ‘the invisible hand’ but as a complex system whose macroscopic explananda emerges from the interactions of its constituent components. Given the estimated volumes of oil originally present before any extraction, simulations show that on average the world peak of crude oil production may happen in the broad vicinity of the time region between 2008 and 2027. Using the proposed petroleum market diversity, the market diversity weakness rapidly towards the peak year.

Within the polarised and contentious debate over future oil supply a growing number of commentators are forecasting a near term peak and subsequent decline in production. But although liquid fuels form the foundation of modern industrial economies, the growing debate on `peak oil has relatively little influence on energy and climate policy. With this in mind, the UK Energy Research Centre (UKERC) has conducted an independent, thorough and systematic review of the evidence, with the aim of establishing the current state of knowledge, identifying key uncertainties and improving consensus. The study focuses upon the physical depletion of conventional oil in the period to 2030 and includes an in-depth literature review, analysis of industry databases and a detailed comparison of global supply forecasts. This Communication summarises the main findings of the UKERC study. A key conclusion is that a peak of conventional oil production before 2030 appears likely and there is a significant risk of a peak before 2020.

This review paper assesses oil supply modeling techniques and critically evaluates their usefulness in projecting future oil production. It reviews models that project future rates of oil production, but does not address estimation of oil resources. The following types of models are reviewed: the Hubbert method; other curve-fitting methods such as exponential and Gaussian models; simulation models of resource discovery and extraction; and data-rich “bottom-up” models. Economic models are reviewed more briefly. Forty-five mathematical models of oil depletion of the last century are classified along four dimensions of variability: emphasis on physical or economic aspects of oil production; model scale; hypothetical or mechanistic orientation; and complexity. Models based on quite disparate assumptions (e.g., physical simulation vs. economic optimal depletion) have produced approximately bell-shaped production profiles, but data do not support assertions that any one model type is most useful for forecasting future oil production. In fact, evidence suggests that existing models have fared poorly in predicting global oil production. The greatest promise for future developments in oil depletion modeling lies in simulation models that combine both physical and economic aspects of oil production.

The global petroleum system is undergoing a shift to substitutes for conventional petroleum (SCPs). The Regional Optimization Model for Emissions from Oil Substitutes, or ROMEO, models this oil transition and its greenhouse gas impacts. ROMEO models the global liquid fuel market in an economic optimization framework, but in contrast to other models it solves each model year sequentially, with investment and production optimized under uncertainty about future prevailing prices or resource quantities. ROMEO includes more hydrocarbon resource types than integrated assessment models of climate change. ROMEO also includes the carbon intensities and costs of production of these resources. We use ROMEO to explore the uncertainty of future costs, emissions, and total fuel production under a number of scenarios. We perform sensitivity analysis on the endowment of conventional petroleum and future carbon taxes. Results show incremental emissions from production of oil substitutes of ≈ 0–30 gigatonnes (Gt) of carbon over the next 50 years (depending on the carbon tax). Also, demand reductions due to the higher cost of SCPs could reduce or eliminate these increases. Calculated emissions are highly sensitive to the endowment of conventional oil and less sensitive to a carbon tax.

The effects of stochastic future oil prices on optimal oil extraction paths and optimal tax, spending and government debt policies are analyzed when demand for oil is linear and preferences quadratic. Without prudence, optimal oil extraction is governed by the Hotelling rule and optimal budgetary policies by the tax smoothing principle. With prudence, the government depletes oil reserves more aggressively and engages in precautionary saving financed by postponing spending and bringing taxes forward, especially if it has substantial monopoly power on the oil market, gives high priority to the public spending target and is very prudent, and future oil demand has high variance. If the oil market is fairly competitive, prudent governments deliberately under-estimate oil reserves and under-predict future oil prices. This leads to less aggressive oil depletion and less government saving. However, if the government attaches high priority to raising public spending to its bliss level, prudence implies a tendency to over-predict future oil prices and reserves which induces more aggressive oil depletion and more government saving. Uncertain economic prospects induce precautionary saving and more aggressive oil extraction.

The global trade in goods depends upon reliable, inexpensive transportation of freight along complex and long-distance supply chains. Global warming and peak oil undermine globalization by their effects on both transportation costs and the reliable movement of freight. Countering the current geographic pattern of comparative advantage with higher transportation costs, climate change and peak oil will thus result in peak globalization, after which the volume of exports will decline as measured by ton-miles of freight. Policies designed to mitigate climate change and peak oil are very unlikely to change this result due to their late implementation, contradictory effects and insufficient magnitude. The implication is that supply chains will become shorter for most products and that production of goods will be located closer to where they are consumed.

The promotion of biofuels as energy for transportation in the industrialized countries is mainly driven by the perspective of oil depletion, the concerns about energy security and global warming. However due to sustainability constraints, biofuels will replace only 10 to 15% of fossil liquid fuels in the transport sector. Several governments have defined a minimum target of GHG emissions reduction for those biofuels that will be eligible to public incentives, for example a 35% emissions reduction in case of biofuels in Members States of the European Union. This article points out the significant biases in estimating GHG balances of biofuels stemming from modelling choices about system definition and boundaries, functional unit, reference systems and allocation methods. The extent to which these choices influence the results is investigated. After performing a comparison and constructive criticism of various modelling choices, the LCA of wheat-to-bioethanol is used as an illustrative case where bioethanol is blended with gasoline at various percentages (E5, E10 and E85). The performance of these substitution options is evaluated as well. The results show a large difference in the reduction of the GHG emissions with a high sensitivity to the following factors: the method used to allocate the impacts between the co-products, the type of reference systems, the choice of the functional unit and the type of blend. The authors come out with some recommendations for basing the estimation of energy and GHG balances of biofuels on principles such as transparency, consistency and accuracy.

The renewable energy industry is growing rapidly amidst rising concerns about oil depletion and climate change. Renewable energy is seen by many as part of the appropriate response to these concerns and some national Governments have put programs in place to support the wider use of sustainable energy systems. This has led to a rapid increase in demand for renewable energy specialists who are able to design, install and maintain such systems. Most engineers are not trained to use these renewable energy technologies and most are not aware of the principles of sustainability. There is therefore an urgent need to develop and implement new courses that prepare engineers, scientists and energy planners to work with renewables to produce sustainable energy generation systems. Renewable energy education is a relatively new field and previously it formed a minor part of traditional engineering courses. These days it has an identity of its own, with special techniques, standards and requirements which are not normally encountered in other disciplines. Attempts to add one or two units of study on renewables into traditional science and engineering degrees are unlikely to produce graduates with sufficient knowledge or understanding to use renewables effectively. Modern renewable energy education includes a study of the technology, resources, systems design, economics, industry structure and policies in an integrated package. This prepares the graduates to design sound systems from amongst the range of options available. There are more pitfalls in the use of renewables than there are in using the more mature conventional technologies and systems. Designers, installers and service personnel need to be particularly aware of the industry and the characteristics of the various firms and their technologies. Over the past decade several new approaches have emerged to renewable energy education that seek to address the needs of the 21st century for sustainable energy supply systems. This paper will describe the aims, philosophy, structure and outcomes of several of these initiatives. It includes courses in renewable energy science, renewable energy engineering, renewable energy policy and planning and renewable energy technician training. The paper will also describe some aspects of the training of researchers in cooperation with the renewable energy industry.

Nearly all researchers into the future of global passenger transport assume that both car-ownership and overall vehicular travel will continue to rise. But they also increasingly acknowledge the environmental and resource problems facing vehicular transport, particularly global climate change and oil depletion. In order to meet these challenges, researchers propose a variety of technological solutions, including greatly improved vehicular fuel efficiency, alternative fuels and propulsion systems, and carbon capture and storage. In this paper we question whether these optimistic solutions can be developed and widely deployed in the limited time frame available, and argue instead that not only are ever-rising vehicular mobility levels unlikely to occur, but that the human costs of continuing this approach are also too great. Instead we argue that because transport is a derived demand, we must first articulate a preferred vision of the future, then design an appropriate, sustainable transport system. Finally, we briefly outline what such a low-mobility future transport system would look like, using our own city, Melbourne, Australia, as a case study.

Over the next 10 years, Scottish tourism is expected to grow by 50%. One of the keys to that growth is transport which is a sector that is dependent upon oil. This paper considers oil and the global economy and its relationship to Scottish tourism. Consideration is given to the key variables such as oil forecasts, security of supply, cost of production, world demand, alternative forms of energy including renewables and nuclear power. The combination of these facts means that high oil prices are here to stay. Two scenarios are constructed called Energy Inflation and Paying for Climate Change. These were developed using a triangulation of methods including the use of systems thinking models to construct the scenarios to computable general equilibrium modelling to analyse the impact of oil and energy price rises on Scottish tourism. The Energy Inflation scenario presumes mass belief in the plenitude of available oil reserves and the failure to respond quickly enough to alter demand. This triggers a sudden and prolonged period of economic shocks, political instability and environmental disasters. The Paying for Climate Change scenario assumes rising energy prices, combined with conservation measures such as carbon taxes. Both scenarios raise a number of policy issues for the future including oil and fossil fuels being the main sources of energy as there is no real alternative. Renewables and nuclear power will continue to grow and countries will try to reduce further their reliance on oil. Rising oil prices are also noted as a positive feature, driving innovation and new technologies, which will become more economic as oil prices rise. For Scottish tourism, the impact of rising oil prices could mean a bumpy ride with carbon taxes, more wind farms and the possible end of the low cost carrier.

In this paper we use results from the Hotelling model of non-renewable resources to examine the hypothesis that technology may increase petroleum reserves. We present empirical evidence from two well-documented mega-oilfields: the Forties in the North Sea and the Yates in West Texas. Patterns of depletion in these two fields suggest that when a resource is finite, technological improvements do increase supply temporarily. But in these two fields, the effect of new technology was to increase the rate of depletion without altering the fields' ultimate recovery - in line with Hotelling's predictions. Our results imply that temporary low prices may be misleading indicators of future resource scarcity and call into question the future ability of current mega-oilfields to meet a sharp increase in oil demand.

Knowledge of petroleum geology defines the size of the World's oil and gas resources, but the reporting of reserves is grossly unreliable. Discovery has been in decline for many years, meaning that production must soon also fall. The decline of oil will have a severe impact on the modern economy which has become dependent on it. Accordingly, a Protocol to match demand against the falling supply, as imposed by Nature, is urgently needed to lessen world tensions and achieve an orderly transition.

This study addresses several questions concerning the peaking of conventional oil production from an optimist's perspective. Is the oil peak imminent? What is the range of uncertainty? What are the key determining factors? Will a transition to unconventional oil undermine or strengthen OPEC's influence over world oil markets? These issues are explored using a model combining alternative world energy scenarios with an accounting of resource depletion and a market-based simulation of transition to unconventional oil resources. No political or environmental constraints are allowed to hinder oil production, geological constraints on the rates at which oil can be produced are not represented, and when USGS resource estimates are used, more than the mean estimate of ultimately recoverable resources is assumed to exist. The issue is framed not as a question of “running out” of conventional oil, but in terms of the timing and rate of transition from conventional to unconventional oil resources. Unconventional oil is chosen because production from Venezuela's heavy-oil fields and Canada's Athabascan oil sands is already underway on a significant scale and unconventional oil is most consistent with the existing infrastructure for producing, refining, distributing and consuming petroleum. However, natural gas or even coal might also prove to be economical sources of liquid hydrocarbon fuels. These results indicate a high probability that production of conventional oil from outside of the Middle East region will peak, or that the rate of increase of production will become highly constrained before 2025. If world consumption of hydrocarbon fuels is to continue growing, massive development of unconventional resources will be required. While there are grounds for pessimism and optimism, it is certainly not too soon for extensive, detailed analysis of transitions to alternative energy sources.

The production and the depletion of mineral resources, and especially oil and fossil fuels, has been an object of extensive predictive modeling. These predictions are often derived from Hubbert's model which is based on the fitting of the experimental data to a symmetric, bell-shaped curve. Although this model describes several historical cases, in particular, crude oil production in the lower 48 US states, not all theoretical models for the “mineral economy” are based on symmetric curves. Also, not much attention has been dedicated so far to the mechanisms which lead to such a behavior. In particular, scarce attention has been dedicated to the factors which may make the production curve asymmetric, e.g. a decline in production more abrupt than the growth. In the present paper, the author uses a stochastic model to examine factors affecting these phenomena. The results of the simulations indicate that the production curves of a non-renewable resource may be asymmetric in dependence on factors such as the search strategy or the presence of technological improvements. Considering worldwide oil production, the simulations indicate that the after-peak downward slope might turn out to be considerably more steep than the upward slope, something that could have unpleasant effects on the economy.

The purpose of this paper is to examine the role of biomass energy in the federal government policies of Canada, Mexico and the USA on the development and utilization of biomass energy. These policies span the entire spectrum from poor to excellent. One of the main driving forces displacing fossil fuels today is environmental issues. But there are still major barriers that are affected by government policies and that must be overcome to facilitate the displacement of large amounts of fossil fuels by biomass. Among these are development of large-scale systems that can supply sustainable amounts of biomass energy and biofuels at competitive prices, and nationwide distribution systems that simplify consumer access. These and other barriers must ultimately be addressed if any federal government decides to institute policies to help establish large-scale biomass energy markets. Otherwise biomass energy utilization will continue to rely on government subsidies and will be limited to niche markets for many years until oil depletion and supply disruptions become a fact of life. This indeed may turn out to be the third oil shock in the 21st century.

This paper, using a six-region dynamic stochastic general equilibrium model of the world economy, assesses the output and current account implications of permanent oil supply shocks hitting the world economy. For modest-sized shocks and conventional production technologies, the effects are modest. But for larger shocks, for elasticities of substitution that decline as oil usage is reduced to a minimum, and for production functions in which oil acts as a critical enabler of technologies, output growth could drop significantly. Also, oil prices could become so high that smooth adjustment, as assumed in the model, may become very difficult.

Oil depletion is outlined as a process which needs to be accommodated in the worlds' cities over the next 40 to 50 years. Due to the timescales in replacing urban structures it is essential to start the process now. The huge variation in petrol use that is found in a global sample of cities, and their different transport and land-use patterns provide the basis for policy directions. Examples of successful implementation of such policies and their benefits are given.

Growing concerns about environment, oil depletion, and traffic congestion call for a fresh look at mass transit—specifically non-polluting, low noise, nonoil-consuming, high-speed electric transit. This article attempts to relate cost to output, both for light rail and the alternative transit mode, i.e., the express bus. For that purpose a simple algebraic framework is developed, tailored to data obtained from a study of alternative transit modes in the Pittsburgh South Hills corridor. The data were prepared by De Leuw Cather and Company for the Port Authority of Allegheny County and were published by the U.S. Department of Transportation in a recent study of the state of light-rail art. The article finds the volume of output at which, considering cost alone, a mass-transit authority would be indifferent between light rail and express buses. At the end, noncost factors are considered.

This paper puts forward a methodology for analysing the impact of alternative oil depletion policies at national level. This is done by developing a long run macroeconomic model and combining it with the method of optimal control. The model presented here is formulated with special reference to North Sea oil in the UK, but it can be applied, with the necessary modifications, to determine depletion strategies to any oil-rich economy.