Energy efficiency Studies Energy policy 129 Energy consumption 79 Energy economics 57 Emissions control 41 Efficiency 38 Analysis 34 Energy conservation 33 Energy use 24 Power efficiency 23 Climate change 22 Energy 22 Usage 22 Environmental policy 20 Sustainable development 20 Electricity generation 17 Energy industry 17 Electricity 16 Households 16 Alternative energy 15 Clean technology 15 Economic aspects 15 Emissions 14 Economic models 13 Greenhouse gases 13 Prices 13 Economic growth 12 Environmental aspects 12 Carbon dioxide 11