Consumption-based indicators such as the energy and greenhouse gas footprint of households are largely determined by their spending levels. An inequality of household expenditures in a population therefore implies an inequality of their resource footprints. Figures 1a-c show European households by decile of expenditure and their associated resource footprints for GHGs and energy in 2015. The figures show that increasing expenditure generally translated into larger resource footprints, but that the inequality decreased from expenditure to energy to greenhouse gas emissions with 10:10 ratios (the top decile divided by the bottom decile) of `r exp_10_10`, `r energy_10_10` and `r co2eq_10_10`, respectively. Total expenditure ranged from `r exp_bottom_decile` trn€ to `r exp_top_decile` trn€ (or `r fd_pae_bottom_decile`€ to `r fd_pae_top_decile`€ per adult equivalent) across bottom and top decile, the energy footprint from `r energy_bottom_decile` EJ to `r energy_top_decile` EJ (or `energy_pae_bottom_decile` GJ/ae to `energy_pae_top_decile` GJ/ae), and the GHG footprint from `r co2eq_bottom_decile` MtCO2eq to `r co2eq_top_decile` MtCO2eq (or `r co2eq_pae_bottom_decile` tCO2eq/ae to `r co2eq_pae_top_decile` tCO2eq/ae). The reason for this is evident from figures 1d-f. Both the energy intensity measured as energy use per € expenditure (d) and the carbon intensity measured as GHGs per unit of energy use (f) gradually decrease from bottom to top expenditure decile. The average energy intensity of consumption decreased from `r mean_energy_intens_bottom_decile` MJ/€ in the bottom decile to less than half (`r mean_energy_intens_top_decile` MJ/€) in the top decile. Additionally, the GHG intensity of energy use was also higher in the bottom decile (`r mean_co2eq_of_energy_intens_bottom_decile` gCO2eq/TJ) compared to the top decile (`r mean_co2eq_of_energy_intens_top_decile` gCO2eq/TJ). There is a clear trend of decreasing intensities across expenditure deciles even though the variance in the lower deciles is much higher. The GHG intensity of consumption (figure 1e) combines the effects of the intensities of 1d and 1f. [*The higher GHG intensity of energy use is likely due to a larger share of emission intensive energy carriers in the energy system. The decreasing energy intensity per expenditure is due to either inefficient energy technologies or energy subsidies in poorer areas in Europe.*]
Consumption-based indicators such as the energy and greenhouse gas footprint of households are largely determined by their spending levels. An inequality of household expenditures in a population therefore implies an inequality of their resource footprints. Figures 1a-c show European households by decile of expenditure and their associated resource footprints for GHGs and energy in 2015. The figures show that increasing expenditure generally translated into larger resource footprints, but that the inequality decreased from expenditure to energy to greenhouse gas emissions with 10:10 ratios (the top decile divided by the bottom decile) of `r exp_10_10`, `r energy_10_10` and `r co2eq_10_10`, respectively. Total expenditure ranged from `r exp_bottom_decile` trn€ to `r exp_top_decile` trn€ (or `r fd_pae_bottom_decile`€ to `r fd_pae_top_decile`€ per adult equivalent) across bottom and top decile, the energy footprint from `r energy_bottom_decile` EJ to `r energy_top_decile` EJ (or `r energy_pae_bottom_decile` GJ/ae to `r energy_pae_top_decile` GJ/ae), and the GHG footprint from `r co2eq_bottom_decile` MtCO2eq to `r co2eq_top_decile` MtCO2eq (or `r co2eq_pae_bottom_decile` tCO2eq/ae to `r co2eq_pae_top_decile` tCO2eq/ae). The reason for this is evident from figures 1d-f. Both the energy intensity measured as energy use per € expenditure (d) and the carbon intensity measured as GHGs per unit of energy use (f) gradually decrease from bottom to top expenditure decile. The average energy intensity of consumption decreased from `r mean_energy_intens_bottom_decile` MJ/€ in the bottom decile to less than half (`r mean_energy_intens_top_decile` MJ/€) in the top decile. Additionally, the GHG intensity of energy use was also higher in the bottom decile (`r mean_co2eq_of_energy_intens_bottom_decile` gCO2eq/TJ) compared to the top decile (`r mean_co2eq_of_energy_intens_top_decile` gCO2eq/TJ). There is a clear trend of decreasing intensities across expenditure deciles even though the variance in the lower deciles is much higher. The GHG intensity of consumption (figure 1e) combines the effects of the intensities of 1d and 1f. [*The higher GHG intensity of energy use is likely due to a larger share of emission intensive energy carriers in the energy system. The decreasing energy intensity per expenditure is due to either inefficient energy technologies or energy subsidies in poorer areas in Europe.*]
```{r figure1, out.width="98%", fig.cap="Expenditure and resource footprints and intensities across European expenditure deciles. Total expenditures (a), energy footprint (b), and GHG footprint (c) per decile. Energy intensity as energy footprint per expenditure (d), GHG intensity as GHG footprint per expenditure (e), and GHG intensity as GHG footprint per energy footprint (f)."}
```{r figure1, out.width="98%", fig.cap="Expenditure and resource footprints and intensities across European expenditure deciles. Total expenditures (a), energy footprint (b), and GHG footprint (c) per decile. Energy intensity as energy footprint per expenditure (d), GHG intensity as GHG footprint per expenditure (e), and GHG intensity as GHG footprint per energy footprint (f)."}
Figure \@ref(fig:figure2) shows that both of these factors play a role. Poorer households on average, spend larger shares of their expenditure in the shelter sector. The bottom and top deciles spend an average of *4% and 11%* of their household expenditures on shelter, respectively. Overall, with increasing expenditure decile, the shares of transport and services expenditures increase and the shares of shelter, food and manufactured goods decrease. At the same time, shelter is by far the most GHG intensive sector with the highest variance between expenditure deciles. In our sample, the intensity of all sectors decreases with expenditure level but the shelter sector stands out with a GHG intensity that is more than 3 times higher in the bottom decile (*6.7* kgCO2eq/€) than in the top decile (*1.7* kgCO2eq/€). Households in the top decile spend about *57*% in the service sector that has the lowset GHG intensity, compared to *37*% in the bottom decile [*wow that is high. correct?*]. Single country studies using MRIO models with national resolution can pick up on differences in consumption baskets but due to the homogeneous technology assumption cannot represent differences in technology between expenditure quantiles.
Figure \@ref(fig:figure2) shows that both of these factors play a role. Poorer households on average, spend larger shares of their expenditure in the shelter sector. The bottom and top deciles spend an average of `r exp_share_shelter_bottom_decile`% and `r exp_share_shelter_top_decile`% of their household expenditures on shelter, respectively. Overall, with increasing expenditure decile, the shares of transport and services expenditures increase and the shares of shelter, food and manufactured goods decrease. At the same time, shelter is by far the most GHG intensive sector with the highest variance between expenditure deciles. In our sample, the intensity of all sectors decreases with expenditure level but the shelter sector stands out with a GHG intensity that is more than 3 times higher in the bottom decile (`r int_co2_shelter_bottom_decile` kgCO2eq/€) than in the top decile (`r int_co2_shelter_top_decile` kgCO2eq/€). Households in the top decile spend about `r exp_share_services_top_decile`% in the service sector that has the lowset GHG intensity, compared to `r exp_share_services_bottom_decile`% in the bottom decile [*wow that is high. correct?*]. Single country studies using MRIO models with national resolution can pick up on differences in consumption baskets but due to the homogeneous technology assumption cannot represent differences in technology between expenditure quantiles.
*The consumption basket aspect has been extensively studied and mostly found to be intuitively true. This is a line of inquiry we do not currently pursue but I just remembered the analysis we did on this which is actually quite interesting: This common sense knowledge could be challenged because it is true mostly in western countries with high demand for heating and cooling and mobility both mostly fossil based and subsidized. In this case, necessities especially shelter (maybe and car based mobility (accessible to most)) have a higher intensity compared to "luxury spending" ie the average intensity of the international supply chain for manufactured goods etc.. It is not true in rich countries with high renewable energy shares (e.g. Norway) where the domestic energy system is more resource efficient than the international supply chain. It is possibly also not true in countries with low heating/cooling demand. We may want to check if that flips after applying the best technology transformation.*
*The consumption basket aspect has been extensively studied and mostly found to be intuitively true. This is a line of inquiry we do not currently pursue but I just remembered the analysis we did on this which is actually quite interesting: This common sense knowledge could be challenged because it is true mostly in western countries with high demand for heating and cooling and mobility both mostly fossil based and subsidized. In this case, necessities especially shelter (maybe and car based mobility (accessible to most)) have a higher intensity compared to "luxury spending" ie the average intensity of the international supply chain for manufactured goods etc.. It is not true in rich countries with high renewable energy shares (e.g. Norway) where the domestic energy system is more resource efficient than the international supply chain. It is possibly also not true in countries with low heating/cooling demand. We may want to check if that flips after applying the best technology transformation.*
In absolute terms, the various final consumption sectors contribute very differently to the total resource footprint of households (Figure 3). On average, shelter and transport are the two largest sectors, accounting for nearly two thirds of both resource footprints. However, there are big differences between the sectors when looking at the respective contributions in the expenditure quantiles. For shelter there is almost no difference (neither in GHG nor in energy footprint). Especially the lower four expenditure deciles have high GHG emissions, which can be explained by the extreme differences in resource intensity shown in Figure 2. Transport was the most unequal sector, with resource footprints *10* times higher in the top decile compared to the bottom deciles (corroborating findings in [@ivanova_quantifying_2020] and [@oswald_large_2020]). Manufactured goods was the second most unequal consumption category (10:10 ratios around *5.3* for both footprints), followed by services (10:10 ratios of *4.4* for GHGs and *4.9* for energy) and then food (10:10 ratios of *2.1* for both footprints).
```{r values-in-text3}
co2eq_per_sector = pdat %>%
filter(indicator_type == "tCO2eq per adult eq") %>%
In absolute terms, the various final consumption sectors contribute very differently to the total resource footprint of households (Figure 3). On average, shelter and transport are the two largest sectors, accounting for nearly two thirds of both resource footprints. However, there are big differences between the sectors when looking at the respective contributions in the expenditure quantiles. For shelter there is almost no difference (neither in GHG nor in energy footprint). Especially the lower four expenditure deciles have high GHG emissions, which can be explained by the extreme differences in resource intensity shown in Figure 2. Transport was the most unequal sector, with resource footprints `r transport_energy_10_10` times higher in the top decile compared to the bottom deciles (corroborating findings in [@ivanova_quantifying_2020] and [@oswald_large_2020]). Manufactured goods was the second most unequal consumption category (10:10 ratios around `r man_goods_energy_10_10` for both footprints), followed by services (10:10 ratios of `r services_co2eq_10_10` for GHGs and `r services_energy_10_10` for energy) and then food (10:10 ratios of `r food_energy_10_10` for both footprints).
```{r figure3, out.width="100%", fig.cap="Energy and GHG footprints by final demand sector and European expenditure decile in 2015 further broken down by emission source location."}
```{r figure3, out.width="100%", fig.cap="Energy and GHG footprints by final demand sector and European expenditure decile in 2015 further broken down by emission source location."}
[*This needs an intro and polish, not clear at the moment why we say this. Maybe only relevant if we pick up reduction options of non-EU emissions in dscussion.*] The shelter footprint was almost entirely domestic, with 26/30% coming from direct household emissions/energy use for heating and cooling, and the rest embedded primarily along the domestic supply chain. The transport footprint was just under 2/3rds domestic. The majority of the transport footprint, above 60%, came from vehicle fuel, either burned directly or indirectly embedded along its supply chain. More than half of the transport footprint's foreign 1/3rd came from outside Europe. The manufactured goods footprint was mostly non-European, while services and food were both around half domestic.
```{r values-in-text4}
co2eq_per_source = pdat %>%
filter(indicator_type == "tCO2eq per adult eq") %>%
[*This needs an intro and polish, not clear at the moment why we say this. Maybe only relevant if we pick up reduction options of non-EU emissions in dscussion.*] The shelter footprint was almost entirely domestic, with `r shelter_co2eq_direct`/`r shelter_energy_direct`% coming from direct household emissions/energy use for heating and cooling, and the rest embedded primarily along the domestic supply chain. The transport footprint was just under 2/3rds domestic. The majority of the transport footprint, above 60%, came from vehicle fuel, either burned directly or indirectly embedded along its supply chain. More than half of the transport footprint's foreign 1/3rd came from outside Europe. The manufactured goods footprint was mostly non-European, while services and food were both around half domestic.
