Rebound and disinvestment effects in refined oil consumption and supply resulting from an increase in energy efficiency in the Scottish commercial transport sector

In this paper, we use an energy–economy–environment computable general equilibrium (CGE) model of the Scottish economy to examine the impacts of an exogenous increase in energy augmenting technological progress in the domestic commercial Transport sector on the supply and use of energy. We focus our analysis on Scottish refined oil, as the main type of energy input used in commercial transport activity. We find that a 5% increase in energy efficiency in the commercial Transport sector leads to rebound effects in the use of oil-based energy commodities in all time periods, in the target sector and at the economy-wide level. However, our results also suggest that such an efficiency improvement may cause a contraction in capacity in the Scottish refined oil supply sector. This ‘disinvestment effect’ acts as a constraint on the size of rebound effects. However, the magnitude of rebound effects and presence of the disinvestment effect in the simulations conducted here are sensitive to the specification of key elasticities of substitution in the nested production function for the target sector, particularly the substitutability of energy for non-energy intermediate inputs to production.     

The effect of energy end-use efficiency improvement on China’s energy use and CO2 emissions: a CGE model-based analysis

With its rapid economic growth, China is now confronted with soaring pressure from both its energy supply and the environment. To deal with this conflict, energy end-use efficiency improvement is now promoted by the government as an emphasis for future energy saving. This study explores the general equilibrium effect of energy end-use efficiency improvement on China’s economy, energy use, and CO₂ emissions. This paper develops a static, multisector computable general equilibrium model (CGE) for China, with specific detail in energy use and with the embodiment of energy efficiency. In order to explore the ability of subsidizing non-fossil-generated electricity on moderating potential rebound effects, in this model, the electricity sector was deconstructed into five specific generation activities using bottom–up data from the Chinese electricity industry. The model is calibrated into a 16-sector Chinese Social Accounting Matrix for the year 2002. In the analysis, seven scenarios were established: business as usual, solely efficiency improvement, and five policy scenarios (taxing carbon, subsidized hydropower, subsidized nuclear power, combination of taxing carbon and subsidized hydropower, combination of taxing carbon and subsidized nuclear power). Results show that a sectoral-uniform improvement of energy end-use efficiency will increase rather than decrease the total energy consumption and CO₂ emissions. The sensitivity analysis of sectoral efficiency improvement shows that efficiency improvements happened in different sectors may have obvious different extents of rebound. The three sectors, whose efficient improvements do not drive-up total national energy use and CO₂ emissions, include Iron and Steel, Building Materials, and Construction. Thus, the improvement of energy end-use efficiency should be sectoral specific. When differentiating the sectoral energy-saving goal, not only the saving potential of each sector but also its potential to ease the total rebound should be taken into account. Moreover, since the potential efficiency improvement for a sector over a certain period will be limited, technology measures should work along with a specific policy to neutralize the rebound effect. Results of policy analysis show that one relatively enhanced way is to combine carbon taxing with subsidized hydropower.     

Negative rebound and disinvestment effects in response to an improvement in energy efficiency in the UK economy

This paper uses a computable general equilibrium (CGE) framework to investigate the conditions under which rebound effects may occur in response to increases in energy efficiency in the UK national economy. Previous work for the UK has suggested that rebound effects will occur even where key elasticities of substitution in production are set close to zero. The research reported in this paper involves carrying out a systematic sensitivity analysis, where relative price sensitivity is gradually introduced into the system, focusing specifically on elasticities of substitution in production and trade parameters, in order to determine conditions under which rebound effects become a likely outcome. The main result is that, while there is positive pressure for rebound effects even where (direct and indirect) demands for energy are very price inelastic, this may be partially or wholly offset by negative income, competitiveness and disinvestment effects, which also occur in response to falling energy prices. The occurrence of disinvestment effects is of particular interest. These occur where falling energy prices reduce profitability in domestic energy supply sectors, leading to a contraction in capital stock in these sectors, which may in turn lead to rebound effects that are smaller in the long run than in the short run, a result that runs contrary to the predictions of previous theoretical work in this area.     

Quantifying the rebound effects of energy efficiency improvements and energy conserving behaviour in Sweden

Doubts have recurrently been raised on the extent to which energy efficiency can reduce the demand for energy. Improvements in efficiency may cause so-called rebound effects by reducing the prices of energy services as well as by increasing the budget for consumption of other goods and services. The magnitude of such effects is crucial to whether energy efficiency should be a strategy for environmental policy or not. This paper aims to derive a general expression of the rebound effects of household consumption in a parameterised form where available data can be tested. The paper analyses how different parameter assumptions affect the quantification of rebound effects and what may be reasonable ranges. Income effects are quantified using data from the Swedish Household Budget Survey of different goods and services split on income classes. The changes in consumption patterns with increasing income are used to establish the composition of marginal consumption. Combined with energy intensities derived from input–output analysis, this gives a model of how money saved on energy use in one sector may lead to increased energy use in other sectors. The total rebound effects of energy efficiency improvements appear to be in the range 5–15% in most cases, but these results are fairly sensitive to assumptions of energy service price elasticities. Cases with low or negative capital costs for energy efficiency improvements may also result in much higher rebound effects as the income effects become more important. Energy-conserving behaviour (reduced energy service demand) affecting direct energy use such as heating and transport gives rise to rebound effects in the order of 10–20%, depending on the household expenditure per primary energy for different fuels and energy carriers.     

Allocation of energy resources for power generation in India: Business as usual and energy efficiency

This paper deals with MARKAL allocations for various energy sources, in India, for Business As Usual (BAU) scenario and for the case of exploitation of energy saving potential in various sectors of economy. In the BAU scenario, the electrical energy requirement will raise up to 5000 bKwh units per year or 752 GW of installed capacity with major consumers being in the industry, domestic and service sectors. This demand can be met by a mix of coal, hydro, nuclear and wind technologies. Other reneawbles i.e. solar and biomass will start contributing from the year 2040 onwards. By full exploitation of energy saving potential, the annual electrical energy demand gets reduced to 3061 bKwh (or 458 GW), a reduction of 38.9%.The green house gas emissions reduce correspondingly. In this scenario, market allocations for coal, gas and large hydro become stagnant after the year 2015.     

Examining the role of energy efficiency and non-economic factors in energy demand and CO2 emissions in Nigeria: Policy implications

This paper examines the role of energy efficiency and non-economic factors such as consumers' preferences, lifestyles and values (which have hitherto been ignored) in energy demand and CO₂ emissions modelling for Nigeria. We use a structural time series model to estimate various energy demand and CO₂ intensity models that take account of the aforementioned factors. We adopt preferred models from these estimates to analyse how energy demand and CO₂ emissions in Nigeria might evolve by generating three different future scenarios to 2025. We find energy efficiency and non-economic factors to influence energy demand and CO₂ emissions. The long-run income and price elasticities obtained differ significantly from those in existing studies that have ignored these salient factors. In a business-as-usual scenario, the results indicate that energy demand will continue to grow. Consequently, present policies do not sufficiently mitigate aggregate CO₂ emissions in Nigeria. The lesson for policy makers is that the extant policies introduced to restrain CO₂ emissions (from a production perspective) have to be combined with new policies that influence consumers' lifestyles and behaviours, develop energy efficient technologies and apply low tariffs on imported energy efficient appliances, to drive down CO₂ emissions from a consumption perspective.     

Electricity and heating system in Kazakhstan: Exploring energy efficiency improvement paths

The Kazakh energy system is less efficient than most other national energy systems. The electricity and heat sub-systems account for about one half of the difference between the primary energy supply and the final consumption. After reviewing the technology chains of electricity and heat generation, transmission and distribution and their organisation, this paper presents scenario studies on the possible evolutions of these sub-systems to 2030. It describes the representation of the heat and electricity chains in the MARKAL–TIMES-Kazakhstan model, with focus on the residential and commercial sectors, and some key input data assumptions. The main scenario drivers are the need to improve the efficiency of electricity and heat in the residential and commercial sectors and to reduce GHG emissions from the energy system as a whole. The model results point to the possibility of achieving cost effective energy efficiency improvement of more than 2% per annum and it would entail a net economic advantage to the country.     

Regional energy rebound effect: The impact of economy-wide and sector level energy efficiency improvement in Georgia,USA

Rebound effect is defined as the lost part of ceteris paribus energy savings from improvements on energy efficiency. In this paper, we investigate economy-wide energy rebound effects by developing a computable general equilibrium (CGE) model for Georgia, USA. The model adopts a highly disaggregated sector profile and highlights the substitution possibilities between different energy sources in the production structure. These two features allow us to better characterize the change in energy use in face of an efficiency shock, and to explore in detail how a sector-level shock propagates throughout the economic structure to generate aggregate impacts. We find that with economy-wide energy efficiency improvement on the production side, economy-wide rebound is moderate. Energy price levels fall very slightly, yet sectors respond to these changing prices quite differently in terms of local production and demand. Energy efficiency improvements in particular sectors (epicenters) induce quite different economy-wide impacts. In general, we expect large rebound if the epicenter sector is an energy production sector, a direct upstream/downstream sector of energy production sectors, a transportation sector or a sector with high production elasticity. Our analysis offers valuable insights for policy makers aiming to achieve energy conservation through increasing energy efficiency.     

The impacts of removing energy subsidies on economy-wide rebound effects in China: An input-output analysis

Facing with the increasing contradiction of economic growth, energy scarcity and environmental deterioration, energy conservation and emissions abatement have been ambitious targets for the Chinese government. Improving energy efficiency through technological advancement is a primary measure to achieve these targets. However, the existence of energy rebound effects may completely or partially offset energy savings associated with technological advancement. This paper adopted a modified input-output model to estimate the economy-wide energy rebound effects across China's economic sectors with the consideration of energy subsidies. The empirical results show that the aggregate rebound effect of China is about 1.9% in 2007–2010, thus technological advancement significantly restrains energy consumption increasing. Removing energy subsidies will cause the aggregate rebound effect declines to 1.53%. Specifically, removing subsidies for coal and nature gas can reduce the rebound effects signifcantly, while removing the subsidies for oil products has a small impact on rebound effect. The existence of rebound effects implies that technological advancement should be cooperated with energy price reform so as to achieve the energy saving target. In addition, the government should consider the diversity of economic sectors and energy types when design the reform schedule.     

Estimating the potential CO2 mitigation from agricultural energy efficiency in the United States

Energy efficiency in agriculture is an underanalyzed aspect of a potential climate change mitigation strategy. According to the Fourth Assessment Report, experts report only medium agreement and medium evidence that energy efficiency can provide substantial reductions (Smith et al. 2007). This paper estimates the CO₂ mitigation potential achievable through improvements in energy efficiency in the US agriculture sector. The data are presented in three formats: the cost data or break-even points of each technology, a marginal abatement supply curve expressed in terms of reduction in energy use by fuel category, and a marginal abatement supply curve expressed in terms of CO₂ emission reductions by fuel category. The largest sources of energy use in the sector were identified as motors used in irrigation systems or other pumping operations; farm machinery such as tractors used in daily farm operations; and space conditioning, such as HVAC systems for livestock and crop-drying systems.

Exploring the driving factors and their mitigation potential in global energy-related CO2 emission

In order to quantify the contribution of the mitigation strategies, an extended Kaya identity has been proposed in this paper for decomposing the various factors that influence the CO₂ emission. To this end, we provided a detailed decomposition of the carbon intensity and energy intensity, which enables the quantification of clean energy development and electrification. The logarithmic mean divisia index (LMDI) has been applied to the historical data to quantify the contributions of the various factors affecting the CO₂ emissions. Further, the global energy interconnection (GEI) scenario has been introduced for providing a systematic solution to meet the 2°C goal of the Paris Agreement. By combining LMDI with the scenario analysis, the mitigation potential of the various factors for CO₂ emission has been analyzed. Results from the historical data indicate that economic development and population growth contribute the most to the increase in CO₂ emissions, whereas improvement in the power generation efficiency predominantly helps in emission reduction. A numerical analysis, performed for obtaining the projected future carbon emissions, suggests that clean energy development and electrification are the top two factors that can decrease CO₂ emissions, thus showing their great potential for mitigation in the future. Moreover, the carbon capture and storage technology serves as an important supplementary mitigation method.     

Voluntary agreements in the field of energy efficiency and emission reduction: Review and analysis of experiences in the European Union

A number of Member States of the EU have introduced voluntary agreements (VAs) that aim to deliver energy savings and emission reductions via increased energy efficiency in different end-use sectors, mainly targeting industry.     

Towards a sustainable energy balance: progressive efficiency and the return of energy conservation

We argue that a primary focus on energy efficiency may not be sufficient to slow (and ultimately reverse) the growth in total energy consumption and carbon emissions. Instead, policy makers need to return to an earlier emphasis on “conservation,” with energy efficiency seen as a means rather than an end in itself. We briefly review the concept of “intensive” versus “extensive” variables (i.e., energy efficiency versus energy consumption) and why attention to both consumption and efficiency is essential for effective policy in a carbon- and oil-constrained world with increasingly brittle energy markets. To start, energy indicators and policy evaluation metrics need to reflect energy consumption, as well as efficiency. We introduce the concept of “progressive efficiency,” with the expected or required level of efficiency varying as a function of house size, appliance capacity, or more generally, the scale of energy services. We propose introducing progressive efficiency criteria first in consumer information programs (including appliance labeling categories) and then in voluntary rating and recognition programs such as ENERGY STAR. As acceptance grows, the concept could be extended to utility rebates, tax incentives, and ultimately to mandatory codes and standards. For these and other programs, incorporating criteria for consumption, as well as efficiency, offers a path for energy experts, policymakers, and the public to begin building consensus on energy policies that recognize the limits of resources and global carrying capacity. Ultimately, it is both necessary and, we believe, possible to manage energy consumption, not just efficiency, in order to achieve a sustainable energy balance. Along the way, we may find it possible to shift expectations away from perpetual growth and toward satisfaction with sufficiency.

Prospective on the energy efficiency and CO2 emissions in the EU cement industry

The cement industry is the third largest carbon emitting industrial sector in the EU. The present work analyses the potential for improvement in the energy efficiency and CO₂ emission reduction for this sector up to 2030. Three scenarios are analysed: baseline scenario (BS) representing the current evolution of the cement sector and two alternative scenarios (AS1 and AS2) studying respectively the sensitivity of fuel prices and CO₂ emission prices. The results for the BS show an improvement in the thermal energy efficiency and the CO₂ emissions per tonne of clinker respectively of 11% and 3.7% in 2030 compared with the level of 2002. However, for AS1 and AS2, these scenarios are insensitive to fuel and CO₂ emission prices, respectively. This can be explained by the fact that a large number of retrofits are economically feasible in the BS, leading to a significant reduction in the thermal energy consumption.     

Influence of the power supply on the energy efficiency of an alkaline water electrolyser

Electric energy consumption represents the greatest part of the cost of the hydrogen produced by water electrolysis. An effort is being carried out to reduce this electric consumption and improve the global efficiency of commercial electrolysers. Whereas relevant progresses are being achieved in cell stack configurations and electrodes performance, there are practically no studies on the effect of the electric power supply topology on the electrolyser energy efficiency. This paper presents an analysis on the energy consumption and efficiency of a 1 N m³ h⁻¹ commercial alkaline water electrolyser and their dependence on the power supply topology. The different topologies of power supplies are first summarised, analysed and classified into two groups: thyristor-based (ThPS) and transistor-based power supplies (TrPS). An Electrolyser Power Supply Emulator (EPSE) is then designed, developed and satisfactorily validated by means of simulation and experimental tests. With the EPSE, the electrolyser is characterised both obtaining its I–V curves for different temperatures and measuring the useful hydrogen production. The electrolyser is then supplied by means of two different emulated electric profiles that are characteristic of typical ThPS and TrPS. Results show that the cell stack energy consumption is up to 495 W h N m⁻³ lower when it is supplied by the TrPS, which means 10% greater in terms of efficiency.     

A comparative study of dynamic changes in CO2 emission performance of fossil fuel power plants in China and Korea

This paper aims to conduct a comparative study of the changes in CO₂ emission performance of state-owned fossil fuel power plants between China and Korea. For this purpose, we combine the concept of the metafrontier Malmquist productivity index and the non-radial directional distance function to develop a new index called the non-radial metafrontier Malmquist CO₂ emission performance index (NMMCPI). This new methodology allows for the incorporation of technological heterogeneities and slack variables into the previously introduced Malmquist CO₂ emission performance index (MCPI). The NMMCPI can be derived by solving several non-radial data envelopment analysis (DEA) models. The NMMCPI can be decomposed into an efficiency change (EC) index, a best-practice gap change (BPC) index, and a technology gap change (TGC) index. By fixing the non-energy inputs, we measure the pure CO₂ emission performance change. Based on the proposed indices, the comparative study between Chinese and Korean fossil fuel power industries is conducted for the 2005–2010 period. Empirical results indicate significant differences in terms of various decomposed CO₂ emission performance changes between China and Korea. Korean power plants demonstrate improvements in innovation, while Chinese power plants demonstrate a higher ability for technological leadership. Some related policy implications are also proposed based on the empirical results.     

Experimental determination of energy and exergy efficiency of the solar parabolic-cooker

A simply designed and the low-cost parabolic-type solar cooker (SPC) was made and tested. The energy end exergy efficiencies of the cooker were experimentally evaluated. The experimental time period was from 10:00 to 14:00 solar time. During this period, it was found that the daily average temperature of water in the SPC was 333 K and the daily average difference between the temperature of water in the cooking pot and the ambient air temperature was 31.6 K. The energy output of the SPC varied between 20.9 and 78.1 W, whereas its exergy output was in the range 2.9–6.6 W. The energy and exergy efficiencies of the SPC were in the range, respectively, 2.8–15.7% and 0.4–1.25%.     

The impact of energy efficiency programs on the growth of electricity sales

With increasing concern about carbon dioxide emissions from power generation, high natural gas costs for generating electricity, and rapidly increasing costs of constructing new power plants, energy efficiency programs are being given greater consideration by utilities and regulators. This study reports on a statistical analysis of the relationship between state-level efficiency program effort and growth in electricity sales between 2001 and 2006 in the United States. The higher the utility efficiency program expenditures per capita and the greater the range of other efficiency programs offered, the greater the reduction in the growth of power sales. Application of the portfolio of energy efficiency programs used in the states with most aggressive programs would have reduced the growth in a state's electricity sales by about 60% relative to the case where no efficiency programs were implemented.     

Assessment of the energy utilization efficiency in the Turkish transportation sector between 2000 and 2020 using energy and exergy analysis method

Energy and exergy utilization efficiencies in the Turkish transportation sector over the period from 2000 to 2020 are evaluated in this study. A comparison of the overall energy and exergy efficiencies of the Turkish transportation sector with the other countries is also presented. Energy and exergy analyses are performed for four transport modes, namely roadway, railway, airway and seaway, while they are based on the actual data for 2000 and projected data for 2020. Roadway appears to be the most efficient mode when compared with railway, air and seaway. It is projected that about 15% of total energy resources will be used in this sector during 2020. The energy utilization efficiencies for the Turkish transportation sector range from 23.71% in 2000 to 28.75% in 2020, while the exergy utilization efficiencies vary from 23.65% to 28.85% in the same years, respectively. Exergetic improvement potential for this sector is estimated to be 700 PJ in 2020, with an average increase rate of 4.5% annually between 2000 and 2020. Road transport and oil-fuelled combustion engines offer the principal scope for exergetic improvement in the coming decades. It may be concluded that the methodology used in this study is practical and useful for analyzing sectoral energy and exergy utilization to determine how efficiently energy and exergy are used in the sector studied. It is also expected that this study will be helpful in developing highly applicable and productive planning for energy policies.     

Integrated resource strategic planning: Case study of energy efficiency in the Chinese power sector

In the last quarter of the 20th century, many power companies used the integrated resource planning (IRP) approach in power expansion planning. Today, very few power companies use this approach because of the split between the power generation and distribution activities. It seems that, in some countries, long-term power system expansion planning has become a task of the central government. To help the government in this area, this paper proposes a new approach called the integrated resource strategic planning (IRSP). When combined with a smart grid, this approach can replace the IRP for the government’s power sector expansion. This paper introduces the necessity and possibility of using this new approach, presents a framework on how to use the approach, and justifies the effectiveness of this approach against the traditional power planning approach, with a case study in China. This paper concludes that if China follows the IRSP approach, it may be able to avoid or postpone up to 69 GW of power generation in the period 2009–2015. These measures could help mitigate 201.8 million tons of carbon dioxide (CO₂), 0.816 million tons of sulfur dioxide (SO₂), and 0.946 million tons of nitrogen oxide (NO_x).