Abstract: The call for a decent life for all within planetary limits poses a dual challenge: Provide all people with the essential resources needed to live well and, collectively, to not exceed the source and sink capacity of the biosphere to sustain human societies. In this paper, we examine the corridor of possible distributions of household energy and carbon footprints for the populations of 28 European countries that satisfy both minimal energy requirements for a decent living and maximum supply of decarbonized energy to achieve the 1.5 degree target in 2050. We constructed energy and carbon footprints for harmonized European expenditure deciles in 2015 by combining data from national Household Budget Surveys (HBS) provided by EUROSTAT with the Environmentally-Extended Multi-Regional Input-Output (EE-MRIO) model EXIOBASE and aggregating the ranked national expenditure quintiles European deciles. Estimates for a range of minimum energy requirements for a decent life, as well as estimates for the maximum available energy supply, were taken from the 1.5 degree scenario literature. We found a top decile to bottom decile ratio of 7.2 for expenditure, 3.5 for energy and 2.6 for carbon, largely attributable to inefficient energy and heating technologies in the four bottom deciles that are predominantly located in Eastern European countries. Adopting best technology in all European deciles would safe 17EJ per year and equalize expenditure, energy and carbon inequality. At those inequality levels, the dual goal can only be achieved by heavy CCS deployment plus large and fast efficiency improvements plus extremely low minimum energy use requirements of 27GJ per adult equivalent (as compared to currently xx GJ/ae in the lowest decile). When around 50GJ/ae minimum energy requirements for a decent living and no CCS deployment is assumed, the mathematical possible inequality to also achieve the 1.5 degree target becomes practically zero. We conclude that for Europe combining the goals of providing enough energy for a decent living and achieving the Paris accord poses an immense and widely underestimated challenge to which the current organization of the euro zone offers little monetary or fiscal leeway.
Abstract: The call for a decent life for all within planetary limits poses a dual challenge: Provide all people with the essential resources needed to live well and, collectively, to not exceed the source and sink capacity of the biosphere to sustain human societies. In this paper, we examine the corridor of possible distributions of household energy and carbon footprints for the populations of 28 European countries that satisfy both minimal energy requirements for a decent living and maximum supply of decarbonised energy to achieve the 1.5 degree target in 2050. We constructed energy and carbon footprints for harmonized European expenditure deciles in 2015 by combining data from national Household Budget Surveys (HBS) provided by EUROSTAT with the Environmentally-Extended Multi-Regional Input-Output (EE-MRIO) model EXIOBASE and aggregating the ranked national expenditure quintiles European deciles. Estimates for a range of minimum energy requirements for a decent life, as well as estimates for the maximum available energy supply, were taken from the 1.5 degree scenario literature. We found a top decile to bottom decile ratio of 7.2 for expenditure, 3.5 for energy and 2.6 for carbon, largely attributable to inefficient energy and heating technologies in the four bottom deciles that are predominantly located in Eastern European countries. Adopting best technology in all European deciles would safe 17EJ per year and equalize expenditure, energy and carbon inequality. At those inequality levels, the dual goal can only be achieved by heavy CCS deployment plus large and fast efficiency improvements plus extremely low minimum energy use requirements of 27GJ per adult equivalent (as compared to currently xx GJ/ae in the lowest decile). When around 50GJ/ae minimum energy requirements for a decent living and no CCS deployment is assumed, the mathematical possible inequality to also achieve the 1.5 degree target becomes practically zero. We conclude that for Europe combining the goals of providing enough energy for a decent living and achieving the Paris agreement poses an immense and widely underestimated challenge to which the current organization of the euro zone offers little monetary or fiscal leeway.
<!-- The following code chunk defines some general settings how code chunks should behave. -->
Decarbonizing the energy system in accordance with the Paris Accord requires a deep transformation of both the supply and the demand side [@grubler_low_2018]. On both sides, however, necessary transformation is restricted by different factors. On the supply side, there exist economic and physical upper limits of how much energy can be provided from renewable sources on the one hand, and how much CO2 removal infrastructure is used to compensate for remaining emissions from fossil fuels on the other. On the demand side [@creutzig_towards_2018], by contrast, there are lower limits to how much energy is minimally required for a decent life [@grubler_low_2018 @millward-hopkins_providing_2020], depending on different assumptions about infrastructures and service provision [@creutzig_towards_2018], as well as the prevalent social ideas about what constitutes decent living [@rao_energy_2019 @millward-hopkins_providing_2020]. Maximum possible energy supply and minimum necessary energy demand describe the corridor in which the simultaneous achievement of climate targets and a decent living for all is possible and, at the same time, restricts the distribution of available energy services among the population. If this dual objective is taken seriously in European climate policy, then there are practical limits to how unequal the society of the future can be, which go beyond the purely political. In fact, a limited energy supply creates an obvious, if rarely acknowledged, zero-sum game where energetic over-consumption by some has to be compensated by less consumption by others.
Decarbonising the energy system in accordance with the Paris agreement requires a deep transformation of both the supply and the demand side [@grubler_low_2018]. On both sides, however, necessary transformation is restricted by different factors. On the supply side, there exist economic and physical upper limits of how much energy can be provided from renewable sources on the one hand, and how much CO2 removal infrastructure is used to compensate for remaining emissions from fossil fuels on the other. On the demand side [@creutzig_towards_2018], by contrast, there are lower limits to how much energy is minimally required for a decent life [@grubler_low_2018 @millward-hopkins_providing_2020], depending on different assumptions about infrastructures and service provision [@creutzig_towards_2018], as well as the prevalent social ideas about what constitutes decent living [@rao_energy_2019 @millward-hopkins_providing_2020]. Maximum possible energy supply and minimum necessary energy demand describe the corridor in which the simultaneous achievement of climate targets and a decent living for all is possible and, at the same time, restricts the distribution of available energy services among the population. If this dual objective is taken seriously in European climate policy, then there are practical limits to how unequal the society of the future can be, which go beyond the purely political. In fact, a limited energy supply creates an obvious, if rarely acknowledged, zero-sum game where energetic over-consumption by some has to be compensated by less consumption by others.
The average household energy footprint of European citizens was around 170 GJ per capita in 2015 [@eurostat_eurostat_nodate-3 @stadler_exiobase_2018], and the household carbon footprint around 7 tonnes CO2eq per capita [@eurostat_eurostat_nodate-4]. However, the differences in average household energy and carbon footprints are large within and between different regions in Europe. Energy footprints ranged from less than 100 GJ per capita to over 300 GJ per capita [@oswald_large_2020], and carbon footprints from below 2.5 tonnes CO2eq per capita to 55 tonnes CO2eq per capita [@ivanova_unequal_2020]. Depending on the assumptions of different global mitigation scenarios, the average footprints likely need to be reduced to between 15.7 and 100 GJ per capita [@grubler_low_2018 @millward-hopkins_providing_2020], or 0.5 and 2.1 tCO2eq per capita [@akenji_1.5-degree_2019] by 2050, respectively.
...
...
@@ -146,9 +146,9 @@ While the European Green Deal already recognizes that inequalities in income, en
## Income-stratified national household energy and carbon footprints
We first used the EE-MRIO model EXIOBASE for 2015 (version3, industry-by-industry) [@stadler_exiobase_2018] and the European household budget survey (HBS) macro-data from EUROSTAT for 2015 [@eurostat_database_nodate] to calculate income-stratified national household energy and carbon footprints (together denoted as environmental footprints in this paper). The EUROSTAT HBS publishes mean household expenditure by income quintile, in purchasing power standard (PPS), by COICOP consumption category, country and year. We chose EXIOBASE as the EE-MRIO for this study because of its European focus, with nearly all countries in the EUROSTAT HBS also found as stand-alone countries in EXIOBASE (see supplementary information (SI), Table S5), its detailed environmental extension data, and its year coverage.
We first used the EE-MRIO model EXIOBASE for 2015 (version3, industry-by-industry) [@stadler_exiobase_2018] and the European household budget survey (HBS) macro-data from EUROSTAT for 2015 [@eurostat_database_nodate] to calculate income-stratified national household energy and carbon footprints (together denoted as environmental footprints in this paper). The EUROSTAT HBS publishes mean household expenditure by income quintile, in purchasing power standard (PPS), by COICOP consumption category, country and year. We chose EXIOBASE as the EE-MRIO for this study because of its European focus, with nearly all countries in the EUROSTAT HBS also found as stand-alone countries in EXIOBASE, its detailed environmental extension data, and its year coverage.
To integrate HBS data into EXIOBASE we created correspondence tables between the EXIOBASE sectors and the matching COICOP consumption categories used in HBS (see SI, Table S4 for details). We then used the relative shares of the COICOP consumption categories of each income quintile in the HBS to decompose the matching EXIOBASE national household final demand expenditure per sector and per income quintile. Using standard input-output techniques (see SI) we calculated ‘total’ (i.e. direct and indirect supply chain) energy use and carbon intensities per EXIOBASE sector and multiplied them with the income-stratified EXIOBASE national household expenditure, to estimate the supply chain part of national household energy and carbon footprints by national income quintile.
To integrate HBS data into EXIOBASE we created correspondence tables between the EXIOBASE sectors and the matching COICOP consumption categories used in the HBS. We then used the relative shares of the COICOP consumption categories of each income quintile in the HBS to decompose the matching EXIOBASE national household final demand expenditure per sector and per income quintile. Using standard input-output techniques we calculated ‘total’ (i.e. direct and indirect supply chain) energy use and carbon intensities per EXIOBASE sector and multiplied them with the income-stratified EXIOBASE national household expenditure, to estimate the supply chain part of national household energy and carbon footprints by national income quintile.
We used the energy use extensions ‘gross total energy use’ from EXIOBASE, which converts final energy consumption in the IEA energy balance data from the territorial to residence principle following SEEA energy accounting [@stadler_exiobase_2018], and the EXIOBASE GHG emission extensions CO2, CH4, N2O, SF6, HFCs and PFCs, from combustion, non-combustion, agriculture and waste, but not land-use change [@stadler_exiobase_2018]. Direct household energy use and carbon emissions are included in the environmental footprints.
...
...
@@ -160,7 +160,7 @@ To calculate European household expenditure deciles we first ranked the national
The unit of analysis for our energy and carbon footprint calculations is the household. We normalized our results to average adult equivalent per household and per national decile as this is how the EUROSTAT HBS publishes its data. The first adult in the household is given a weight of 1.0, each adult thereafter 0.5, and each child 0.3 [@eurostat_description_2016].
For our calculations of attainable corridors for achieving the dual goal of climate protection and a decent standard of living for all, we adjusted the total per capita results from published 1.5 degree scenarios to household adult equivalents in order to better compare them with our environmental footprint estimates (see SI, pp xx for details). Estimates of minimum final energy for a decent living are from Grubler et al. (2018) [@grubler_low_2018] and Millward-Hopkins et al. (2020) [@millward-hopkins_providing_2020], while maximum final energy compatible with the 1.5 degree target is from the decarbonization scenarios in the IIASA scenario database [@riahi_shared_2017 @gea_gea_nodate].
For our calculations of attainable corridors for achieving the dual goal of climate protection and a decent standard of living for all, we adjusted the total per capita results from published 1.5 degree scenarios to household adult equivalents in order to better compare them with our environmental footprint estimates. Estimates of minimum final energy for a decent living are from Grubler et al. (2018) [@grubler_low_2018] and Millward-Hopkins et al. (2020) [@millward-hopkins_providing_2020], while maximum final energy compatible with the 1.5 degree target is from the decarbonisation scenarios in the IIASA scenario database [@riahi_shared_2017 @gea_gea_nodate].
As inequality measure we use the 10:10 ratio, i.e. the expenditure or the environmental footprint of the top European expenditure decile divided by that of the bottom European expenditure decile. Thus, an expenditure 10:10 ratio of 5 means that one adult equivalent in the top decile spent 5 times more on average than one adult equivalent in the bottom decile.
Based on this counterfactual distribution of the energy footprint using homogeneous supply technologies, we can now scale down energy use across European expenditure deciles to meet supply constraints and, where necessary, "squeeze" the distribution to not undershoot minimum energy use requirements in any decile (Figure 5).
Both the DLE and LED scenarios satisfy energy demand for decent living and are compatible with the 1.5 degree target without resorting to CCS technologies [@millward-hopkins_providing_2020 @grubler_low_2018]. The DLE scenario explicitly envisions absolute global equality (10:10 ratio of 1) in consumption, except for small differences in required energy consumption based on climatic and demographic factors, as well as differences in population density [@millward-hopkins_providing_2020]. The LED scenario does not explicitly discuss distributional aspects beyond giving different final energy values for the Global North (53 GJ/ae) and the Global South (27 GJ/ae) [@grubler_low_2018]. However, due to the bottom-up construction of this demand scenario, these values can be interpreted as estimates for the minimum required energy use.
The descriptions of the energy supply scenarios do not include specific details about how the energy footprints are distributed within the population. The energy savings here are achieved primarily through efficiency improvements, and perhaps also generally assumed demand reductions.
Both the DLE and LED scenarios satisfy energy demand for decent living and are compatible with the 1.5 degree target without resorting to CCS technologies [@millward-hopkins_providing_2020 @grubler_low_2018]. The DLE scenario explicitly envisions absolute global equality (10:10 ratio of 1) in consumption, except for small differences in required energy consumption based on climatic and demographic factors, as well as differences in population density [@millward-hopkins_providing_2020]. The LED scenario does not explicitly discuss distributional aspects beyond giving different final energy values for the Global North (53 GJ/ae) and the Global South (27 GJ/ae) [@grubler_low_2018]. However, due to the bottom-up construction of this demand scenario, these values can be interpreted as estimates for the minimum required energy use. The energy supply scenarios achieve energy savings through the replacement of carbon-intensive fossil fuels by cleaner alternatives, efficiency improvements, including the electrification of energy demand, and measures towards energy conservation [@riahi_shared_2017].
```{r figure5, out.width="70%", fig.align="center", fig.cap="Mean energy available for Europe in decarbonisation scenarios, positioned in option space between a range of minimum energy requirements and range of associated maximum inequality. All expenditure deciles have 'best technology' already."}
