COURT Victor

Information and communication technologies (ICTs) increasingly enable employees to work from home and other locations ('teleworking'). This study explores the extent to which teleworking reduces the need to travel to work and the consequent impacts on economy-wide energy consumption. The paper provides a systematic review of the current state of knowledge of the energy impacts of teleworking. This includes the energy savings from reduced commuter travel and the indirect impacts on energy consumption associated with changes in non-work travel and home energy consumption. The aim is to identify the conditions under which teleworking leads to a net reduction in economy-wide energy consumption, and the circumstances where benefits may be outweighed by unintended impacts. The paper synthesises the results of 39 empirical studies, identified through a comprehensive search of 9000 published articles. Twenty six of the 39 studies suggest that teleworking reduces energy use, and only eight studies suggest that teleworking increases, or has a neutral impact on energy use. However, differences in the methodology, scope and assumptions of the different studies make it difficult to estimate 'average' energy savings. The main source of savings is the reduced distance travelled for commuting, potentially with an additional contribution from lower office energy consumption. However, the more rigorous studies that include a wider range of impacts (e.g. non-work travel or home energy use) generally find smaller savings. Despite the generally positive verdict on teleworking as an energy-saving practice, there are numerous uncertainties and ambiguities about its actual or potential benefits. These relate to the extent to which teleworking may lead to unpredictable increases in non-work travel and home energy use that may outweigh the gains from reduced work travel. The available evidence suggests that economy-wide energy savings are typically modest, and in many circumstances could be negative or non-existent.

Using the gross world product (GWP) as the only exogenous input variable, we design a model able to accurately reproduce the global population dynamics over the period 1950-2015. For any future increasing GWP scenarios, our model yields very similar population trajectories. The major implication of this result is that both the United Nations and the Intergovernmental Panel on Climate Change assume future decoupling possibilities between economic development and fertility that have never been witnessed during the last sixty-five years. In case of an abrupt collapse of the economic production, our model responds with higher death rates that are more than offset by increasing birth rates, leading to a relatively larger and younger population. Finally, we add to our model an excess mortality function associated with climate change. Estimates of additional climate-related deaths for 2095-2100 range from 1 million in a +2 • C scenario to 6 million in a +4 • C scenario.

Information and communication technologies (ICTs) increasingly enable employees to work from home and other locations (‘teleworking’). This study explores the extent to which teleworking reduces the need to travel to work and the consequent impacts on economy-wide energy consumption, with clear implications for climate, energy, and environmental policy. Methods/Design: This review assesses how changes in working practices are associated with different forms of teleworking, including the use of different ICTs, various commuting/travel options, and different working spaces such as offices, cafes, libraries, and homes. To do so, it conducts a review of more than 9,000 published articles. Review results/Synthesis: Overall, the review finds that 26 out of 39 relevant studies indicate that teleworking causes a reduction in energy use, and only eight studies indicate that teleworking leads to an increase (or only a neutral impact) on energy use. The main source of energy savings is via the substitution effect whereby teleworking leads to lower average vehicle distance travelled by those who telework either part of the week. The studies estimated that potential reductions in energy consumption as a result of reduced commuting travel could be as high as 20%. Other studies suggest possible energy savings through lower office energy consumption. Discussion: Despite the generally positive verdict on teleworking as an energy-saving practice, analysis reveals that there are numerous uncertainties and ambiguities about the actual or potential benefits of teleworking. These relate to questions about exactly what proportion of workers or frequency of teleworking is needed to bring a net reduction in energy use through avoided work travel. They also relate to questions about the extent to which teleworking may lead to unpredictable increases in non-work travel and home energy consumption that end up outweighing any gains from reduced work travel.

Because energy is usually absent from modern growth analysis, Unified growth models designed to study the economic take-off process have tended to focus on the role of human capital accumulation and its interaction with technical change. However, prominent economic historians claim that the transition to coal and its use in steam engines was the main driver of the Industrial Revolution. In order to try to reunite these diverging point of views, we provide in this article a quantitative analysis of the role of energy in long-term growth, accounting for the interaction between human capital accumulation and technological change. To do so, we design a unified growth model featuring fertility and educational choices, energy resources extraction, directed technical change, and endogenous general purpose technologies (GPTs) diffusion. The associated energy transition results from the endogenous shortage in the availability of renewable resources (wood), and the arrival of new GPTs that, together, redirect technical change towards the exploitation of previously unprofitable exhaustible energy (coal). A calibrated version of the model replicates the historical episode of the British Industrial Revolution, for which counterfactual simulations are performed to characterize the impact of the energy transition on the timing and magnitude of the economic take-off. Another numerical exercise provides a comparative analysis of Western Europe and Eastern Asia, emphasizing the relevance of discrepancies in terms of energy resources accessibility to explain the diverging dynamics of these two world regions. Our findings show that, whenever demographic dynamics and human capital accumulation are accounted for, energy use appears as a vital catalyst for the economic take-off process.

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This article provides a knowledge-based and energy-centred unified growth model of the transition from limited to sustained economic growth. We model the transition between: (i) a pre-modern organic regime defined by limited growth in per capita output, high fertility, low levels of human capital, technical change generated by learning-by-doing, and rare general purpose technology (GPT) arrivals. and (ii) a modern fossil regime characterized by sustained growth in per capita output, low fertility, high levels of human capital, technical change generated by profit-motivated R&D, and increasingly frequent GPT arrivals. The associated energy transition results from the endogenous shortage in the availability of renewable resources, and the arrival of new GPTs that, together, redirect technical change towards the exploitation of previously unprofitable exhaustible energy. A calibrated version of the model replicates the historical experience of Great Britain from 1700 to 1960. Counterfactual simulations are performed to characterize the impact of the energy transition on the timing and magnitude of the British economic take-off. Another simulation exercise compares the different trajectories of Western Europe and Eastern Asia to determine which parameters of our model are the most crucial to reflect the diverging dynamics of these two world regions.

No summary available.

This article provides a knowledge-based and energy-centred unified growth model of the transition from limited to sustained economic growth. We model the transition between: (i) a pre-modern organic regime defined by limited growth in per capita output, high fertility, low levels of human capital, technical change generated by learning-by-doing, and rare general purpose technology (GPT) arrivals. and (ii) a modern fossil regime characterized by sustained growth in per capita output, low fertility, high levels of human capital, technical change generated by profit-motivated R&D, and increasingly frequent GPT arrivals. The associated energy transition results from the endogenous shortage in the availability of renewable resources, and the arrival of new GPTs that, together, redirect technical change towards the exploitation of previously unprofitable exhaustible energy. A calibrated version of the model replicates the historical experience of Great Britain from 1700 to 1960. Counterfactual simulations are performed to characterize the impact of the energy transition on the timing and magnitude of the British economic take-off. Another simulation exercise compares the different trajectories of Western Europe and Eastern Asia to determine which parameters of our model are the most crucial to reflect the diverging dynamics of these two world regions.

No summary available.

This article builds a bridge between the endogenous economic growth theory, the biophysical economics perspective, and the past and future transitions between renewable and nonrenewable energy forms that economies have had to and will have to accomplish. We provide an endogenous economic growth model subject to the physical limits of the real world, meaning that nonrenewable and renewable energy production costs have functional forms that respect physical constraints, and that technological level is precisely defned as the effciency of primary-to-useful exergy conversion. The model supports the evidence that historical productions of renewable and nonrenewable energy have greatly infuenced past economic growth. Indeed, from an initial almost-renewable-only supply regime we reproduce the increasing reliance on nonrenewable energy that has allowed the global economy to leave the state of economic stagnation that had characterized the largest part of its history. We then study the inevitable transition towards complete renewable energy that human will have to deal with in a not-too-far future since nonrenewable energy comes by defnition from a fnite stock. Through simulation we study in which circumstances this transition could have negative impacts on economic growth (peak followed by degrowth phase). We show that the implementation of a carbon price can partially smooth such unfortunate dynamics, depending on the ways of use of the income generated by the carbon pricing.

This article builds a bridge between the endogenous economic growth theory, the biophysical economics perspective, and the past and future transitions between renewable and nonrenewable energy forms that economies have had to and will have to accomplish. We provide an endogenous economic growth model subject to the physical limits of the real world, meaning that nonrenewable and renewable energy production costs have functional forms that respect physical constraints, and that technological level is precisely defned as the effciency of primary-to-useful exergy conversion. The model supports the evidence that historical productions of renewable and nonrenewable energy have greatly infuenced past economic growth. Indeed, from an initial almost-renewable-only supply regime we reproduce the increasing reliance on nonrenewable energy that has allowed the global economy to leave the state of economic stagnation that had characterized the largest part of its history. We then study the inevitable transition towards complete renewable energy that human will have to deal with in a not-too-far future since nonrenewable energy comes by defnition from a fnite stock. Through simulation we study in which circumstances this transition could have negative impacts on economic growth (peak followed by degrowth phase). We show that the implementation of a carbon price can partially smooth such unfortunate dynamics, depending on the ways of use of the income generated by the carbon pricing.

This article build a bridge between the endogenous economic growth theory, the biophysical economics perspective, and the past and future transitions between renewable and nonrenewable energy forms that economies have had to and will have to accomplish. We provide an endogenous economic growth model subject to the physical limits of the real world, meaning that nonrenewable and renewable energy production costs have functional forms that respect physical constraints, and that technological level is precisely defined as the efficiency of primary-to-useful exergy conversion. The model supports the evidence that historical productions of renewable and nonrenewable energy have greatly influenced past economic growth. Indeed, from an initial almost-renewable-only supply regime we reproduce the increasing reliance on nonrenewable energy that has allowed the global economy to leave the state of economic stagnation that had characterized the largest part of its history. We then study the inevitable transition towards complete renewable energy that human will have to deal with in a not-too-far future since nonrenewable energy comes by definition from a finite stock. Through simulation we study in which circumstances this transition could have negative impacts on economic growth (peak followed by degrowth phase). We show that the implementation of a carbon price can partially smooth such unfortunate dynamics, depending on the ways of use of the income generated by the carbon pricing.

We use a price-based methodology to assess the global energy-return-on-investment (EROI) of coal, oil, and gas, from the beginning of their reported production (respectively 1800, 1860, and 1890) to 2012. It appears that the EROI of global oil and gas productions reached their maximum values in the 1930s–40s, respectively around 50:1 and 150:1, and have declined subsequently. Furthermore, we suggest that the EROI of global coal production has not yet reached its maximum value. Based on the original work of Dale et al. (2011), we then present a new theoretical dynamic expression of the EROI. Modifications of the original model were needed in order to perform calibrations on each of our price-based historical estimates of coal, oil, and gas global EROI. Theoretical models replicate the fact that maximum EROIs of global oil and gas productions have both already been reached while this is not the case for coal. In a prospective exercise, the models show the pace of the expected EROIs decrease for oil and gas in the coming century. Regarding coal, models are helpful to estimate the value and date of the EROI peak, which will most likely occur between 2025 and2045, around a value of 95(±15):1.

We use a price-based methodology to assess the global energy-return-on-investment (EROI) of coal, oil, and gas, from the beginning of their reported production (respectively 1800, 1860, and 1890) to 2012. It appears that the EROI of global oil and gas productions reached their maximum values in the 1930s.

We use a price-based methodology to assess the global energy-return-on-investment (EROI) of coal, oil, and gas, fromthe beginning of their reported production (respectively 1800, 1860, and 1890) to 2012. It appears that the EROI of global oil and gas productions reached their maximumvalues in the 1930s–40s, respectively around 50:1 and 150:1, and have declined subsequently. Furthermore, we suggest that the EROI of global coal production has not yet reached its maximumvalue. Based on the originalwork of Dale et al. (2011), we then present a new theoretical dynamic expression of the EROI.Modifications of the originalmodelwere needed in order to performcalibrations on each of our price-based historical estimates of coal, oil, and gas global EROI. Theoretical models replicate the fact that maximum EROIs of global oil and gas productions have both already been reached while this is not the case for coal. In a prospective exercise, the models show the pace of the expected EROIs decrease for oil and gas in the coming century. Regarding coal, models are helpful to estimate the value and date of the EROI peak, which will most likely occur between 2025 and 2045, around a value of 95(±15):1.

We estimate energy expenditure for the US and world economies from 1850 to 2012. Periods of high energy expenditure relative to GDP (from 1850 to 1945), or spikes (1973–74 and 1978–79) are associated with low economic growth rates, and periods of low or falling energy expenditure are associated with high and rising economic growth rates (e.g. 1945–1973). Over the period 1960–2010 for which we have continuous year-to-year data for control variables (capital formation, population, and unemployment rate) we estimate that, statistically, in order to enjoy positive growth, the US economy cannot afford to spend more than 11% of its GDP on energy. Given the current energy intensity of the US economy, this translates in a minimum societal EROI of approximately 11:1 (or a maximum tolerable average price of energy of twice the current level). Granger tests consistently reveal a one way causality running from the level of energy expenditure (as a fraction of GDP) to economic growth in the US between 1960 and 2010. A coherent economic policy should be founded on improving net energy efficiency. This would yield a “double dividend”: increased societal EROI (through decreased energy intensity of capital investment), and decreased sensitivity to energy price volatility.

The purpose of this thesis is to study the role of energy in long-term economic growth. Chapter 1 describes the four main facts of growth: the transition from stagnation to sustainability, the Great Divergence, the interdependence between energy consumption and technical progress, and the dynamics in nested and hierarchical cycles. The various remote causes of growth (biogeography, culture, institutions and contingency) are then studied. Chapter 2 presents the theories involving so-called proximate causes, such as technical progress and the accumulation of physical and human capital. The unified growth theory (UGT) is also analyzed. Chapter 3 presents the fundamental laws of thermodynamics and the associated concepts of exergy and entropy. It is then shown that only the consumption of exergy services is a fundamental cause of growth. In chapter 4, it is established that world oil and gas production (but not coal) has already exceeded its maximum energy rate of return (EROI), so that future conventional production will be with a decreasing EROI. Chapter 5 shows that the higher metal requirements of renewable technologies could be a constraint to the successful feasibility of the energy transition. Chapter 6 shows that the net energy constraint materializes in the short term through the energy expenditure (share of the economic product consumed to obtain energy). Chapter 7 presents a theoretical model of endogenous growth integrating the biophysical approach.

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More and more attention is being paid to renewable technologies because they are seen as a great opportunity to disengage our society from its dependence on fossil fuels. Such flow-based energy resources that rely on solar energy are supposed to lead us toward a sustainable energy future. However, because of their high capital intensity, renewable technologies require large amounts of matter, including both common and rare metals. These metals require energy for their production, and more specifically for their extraction. The energy cost associated with metal extraction is linked to mineral ore grade, meaning that as depletion progresses, energy cost increases. In addition, renewable energy resources deliver less net energy to society compared to fossil fuels, because of their diffuse nature. It is therefore easy to see that a close relationship exists between energy and metal sectors. In this article, we describe more precisely this relationship by investigating how the energy requirement associatedwith metal extraction could impact the energy-return-on-investment (EROI) of different renewable and nuclear technologies.More precisely,we present a methodology that can be used to calculate the sensitivity of the EROI of a given technology to a specific or to multiple metal ore grade degradation. We found that if considered separately, the qualitative depletion of a given metal has no significant impact on the EROI of renewable and nuclear technologies, unless its concentration approaches very low grade. However, if all metals are considered together, the EROI of these same technologies could be importantly diminished, especially if they tend to very low concentrations.

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