176
match. In order to obtain the new energy consumption estimates from coal, natural
gas, and liquid fuels shown in Fig. 4.3a, we have used the ratio of quad BTU per
year provided from each source divided by the Gt CO 2 released from each source,
extracted from the EIA baseline projection. For those keeping score at home, in year
2040 these three ratios are 18.90, 15.82, and 10.93 quad BTU/Gt CO 2 for natural
gas, liquid fuels, and coal, respectively. Finally, the shortfall in meeting the global
demand for energy, caused by the decline in fossil fuel-based production needed to
meet RCP 4.5 emission of CO 2 , is assigned to the renewables category.
Figure 4.4 shows energy production by renewables broken into two wedges:
energy from the combustion of biomass (dark green) and other sources of renewable
energy (light green). The sum of the biomass and other wedges in Fig. 4.4a matches,
by design, the renewable time series shown in Fig. 4.2a. The numerical values of
energy production from renewables other than biomass shown in Fig. 4.4a are based
on electricity production from renewables projections for 2012 to 2040 in:
http://www.eia.gov/forecasts/ieo/excel/figure5-4_data.xls
For years 2001–2011, the apportionment of biomass versus others was based on
information archived in Organization for Economic Co-operation and Development
(OECD), International Energy Administration (IEA) annual Renewables
Information reports, available on the web at:
http://www.oecd-ilibrary.org/energy/renewables-information_20799543.
For 2000 and years prior, we assumed 80 % of total global energy from renewables
had been supplied by biomass, which is the IEA percentage for 2001 and 2002. For
Fig. 4.4b, we assign to “other” all of the new energy from renewables needed to
match RCP 4.5 emissions of CO 2. The size of this wedge is enormous: it exceeds the
world demand for electricity in the latter years. For this reason, this wedge is labeled
“renewable sources of energy for industry, electricity, transportation, and
building”.
Figure 4.5 is similar to Fig. 4.3, except the target for emissions of CO 2 is RCP
2.6 (van Vuuren et al. 2011 ). The RCP2.6 emissions originate from file:
http://www.pik-potsdam.de/~mmalte/rcps/data/RCP3PD_EMISSIONS.DAT
The use of 3PD in this filename is due to the fact some researchers had called this
scenario RCP 3 Peak and Decline, rather than RCP 2.6. The analysis procedure (i.e.,
adjustment for CO 2 from cement and gas flaring; preservation of the EIA ratios of
coal, natural gas, and liquid fuels, etc.) is the same as described above. For illustra-
tive purposes, and since the design of RCP 2.6 (van Vuuren et al. 2011 ) mentions
carbon capture and sequestration (CCS) whereas the design of RCP 4.5 (Thomson
et al. 2011 ) does not consider this still developing technology, we have kept the
renewable wedge in Fig. 4.5a the same as the renewable wedge in Fig. 4.3a, and
assigned to CCS the new shortfall needed to achieve RCP 2.6 emissions of CO 2.
Figure 4.6 shows global maps of population and night lights. The population
data (Doxsey-Whitfield et al. 2015 ) were obtained from file:
gpw-v4-population-density-adjusted-to-2015-unwpp-country-totals-2015.zip
downloaded from the NASA SEDAC website at:
http://beta.sedac.ciesin.columbia.edu/data/set/gpw-v4-population-density-
adjusted- to-2015-unwpp-country-totals/data-download
4 Implementation