Subject
energy policy
139
energy economy
119
energy supply
45
energy
36
renewable energy
36
energy demand
26
world energy consumption
26
energy production
23
energy transition
22
energy resource
18
energy system
17
energy prognosis
16
energy conservation
15
energy statistics
15
environmental policy
14
energy consumption
12
European Union
11
energy management
11
hydroelectric power
11
energy source
10
energy technology
10
future aspect
10
geothermal energy
10
nuclear controversy
10
solar energy
10
bioconversion to fuel
9
climatic change
9
coal gasification
9
energy analysis
9
nuclear energy
9
nuclear power
9
energy model
8
wind energy
8
coal
7
energy conversion
7
energy program
7
renewable energy source
7
coal liquefaction
6
cogeneration
6
environment
6
photovoltaic conversion
6
regional energy planning
6
solar cell
6
sustainable development
6
biomass energy production
5
electric power generation
5
energy storage
5
fusion technology
5
hydrogen energy
5
ocean thermal energy
5
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