Definition of sustainable development

Sustainability = Dynamic efficiency + Intergenerational equity

• Dynamic efficiency（动态效率）: maximize present value of net benefits
• Intergenerational equity（代际公平）: non-decreasing social welfare over time

What are the three dimensions of the energy “impossible” triangle?

Which one has larger improvement room in China: energy/GDP（增长很快） and CO2/energy（仍有增长空间）?