vgbe energy journal 11 (2022) - International Journal for Generation and Storage of Electricity and Heat

Future Energy Systems
Tab. 2. Definition and share of Scenario types used in energy system studies.
Scenario type Share Definition
Trend 12 % Trend scenarios are based on the extrapolation of current
political and legal measures into the future. Therefore, no
additional expansion targets or other further constraints are
imposed on the model.
Reference 16 % The term reference scenario is generally used to describe
scenarios that are used as the basis of a more advanced
comparison. Moderate developments are often assumed for
the future, which means that trend scenarios are usually used
as a reference.
High ambition 46 % Ambitious scenarios refer to scenarios that go beyond current
policies. In most cases, this means a faster or stronger
reduction of greenhouse gas emissions or an accelerated
expansion of renewable energies. However, this can also mean
societal aspects, such as a change in values toward energysaving
behaviors.
Low ambition 12 % Low-ambition scenarios represent the opposite compared to
the ambitious ones. Climate protection targets are given low
priority overall. For example, existing climate protection
measures are dropped or missed. Also considered here is
possible societal unacceptance toward savings measures or
individual technologies.
Others 14 % If a scenario cannot be assigned to any of the four categories
mentioned, it is classified as another scenario.
Tab. 3. Overview of the evaluated characteristics.
Characteristic high mid low NA Definition
Society 8 % 71 % 7 % 14 % Social acceptance and support
Ambition 39 % 44 % 17 % 0 % Level of ambition of climate protection
measures
Certainty 41 % 44 % 5 % 10 % Probability of assumptions occurring
Grid 53 % 25 % 7 % 15 % Flexibility of domestic transmission
Trade 56 % 7 % 19 % 19 % Role of EU-wide import/export
Openness 54 % 17 % 27 % 2 % Degree of predictability of the future
energy system
Sector coupling 56 % 24 % 2 % 19 % Degree of electrification in the heat and
mobility sectors
Speed 31 % 22 % 19 % 29 % Speed of implementation of energy policy
measures
Characteristic Yes No NA Definition
Coal phase-out 40 % 37 % 23 % Fixed phase-out target for 2038
Nuclear phase-out 87 % 0 % 13 % No use of nuclear power after 2022
80 % GHG 1 reduction 57 % 7 % 36 % Achieve the reduction target of -80 %
compared to 1990
95 % GHG 1 reduction 38 % 26 % 36 % Achieve the reduction target of -95 %
compared to 1990
1
GHG: greenhouse gas
os in energy system studies. A list of the characteristics
used in this work, their definition
and their respective share per gradation is
summarized in Ta b l e 3 .
3 Results
The following section serves to summarize
the results of our study. Section first presents
the general trend of the future development
of the German energy system. This
is followed in section 3.2 by an analysis of
the boundary conditions as an influence on
the development of energy systems.
3.1 Summary of general trends
This section is intended to present general
trends in energy supply in a possible future
German energy system. First, electricity
generation via renewables and the demand
for conventional power plants will be discussed,
before topics such as the increasing
demand for hydrogen and sector coupling
are addressed. For a simplified representation
of the data, the median, upper and lower
quartile, and total range of the evaluated
data subset is used und presented in different
shading. Additionally, in the upper part
of the figures nsum and nmin represent the
total number of used scenarios and the minimum
number of scenarios for each considered
timestep.
3.1.1 Power generation
Key parameters for describing an energy system
are for example its total energy requirements
and the associated greenhouse gas
emissions. F i g u r e 1 (A) shows the assumed
gross electricity consumption in Germany
as an example. While older studies
still assumed an almost constant demand
over the coming decades, more recent studies
are already showing the strong influence
of electrification. The interquartile ranges
from 600 to 905 TWh in 2050. Scenarios
with strong electrification and high hydrogen
supply within Germany even expect up
to 2000 TWh. Additionally, in F i g u r e 1
(B) the greenhouse gas emissions are
shown. Only about a quarter of the scenarios
exceed the original reduction targets
of up to 95 % by 2050. Current targets for
an energy system with net zero emissions
are only represented to a limited extent, as
most of the studies were published before
the German climate targets have been updated.
Median Range lnterquartile
n sum = 88; n min = 46 n sum = 47; n min = 23
Gross electricity demand in TWh
2000
1500
1000
500
0
(A) - Gross electricity demand
(B) - GHG emissions
2020 2025 2030 2035 2040 2045 2050 2020 2025 2030 2035 2040 2045 2050
Fig. 1. Expected gross electricity consumption (A) and greenhouse gas emissions (B).
800
600
400
200
0
Greenhouse gas emissions in Mt CO2e
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