可再生能源与能源效率的协同作用（英文版）_121页-2mb

Summary of "Synergies between Renewable Energy and Energy Efficiency"

Core Content

This IRENA working paper explores the synergies between renewable energy (RE) and energy efficiency (EE) in achieving global climate and sustainability goals. It is based on the REmap initiative, which aims to significantly increase the share of renewable energy in the global energy mix by 2030 and to explore its long-term implications for decarbonisation up to 2050.

Main Points

• Synergies between RE and EE are essential for achieving deep carbon reductions and sustainable development.
• The combination of RE and EE can lead to higher renewable energy shares, faster reduction in energy intensity, and lower energy system costs.
• By 2050, renewables could account for two-thirds of the world's energy supply, with energy efficiency contributing 45% to emission reductions.
• The Paris Agreement underscores the need for decarbonisation of the energy system, which is responsible for almost two-thirds of global GHG emissions.

Key Information

Synergies in Technology and Sector Coupling

• Technologies such as solar PV, wind, geothermal, bioenergy, and solar thermal show strong synergies with EE.
• Sector coupling (power, heat, and mobility) is crucial for integrating variable renewables into the grid and improving system efficiency.
• Electrification of end-use services (e.g., transport and heating) increases efficiency and enables the deployment of renewable power.

Country-Level Analysis

• The report focuses on five major G20 countries: China, Germany, India, Japan, and the United States, which account for two-thirds of the G20's TPES and about half of global energy demand.
• Energy efficiency is particularly effective in India and China, where it significantly slows energy demand growth.
• Renewable energy has the greatest impact on Germany, Japan, and the United States.

Cost and Benefit Analysis

• Energy efficiency technologies are generally more cost-competitive than renewable energy options, but both are needed for long-term climate goals.
• Combined deployment of RE and EE leads to significant cost savings in the energy system, especially when externalities such as air pollution and health impacts are considered.
• Cost savings from RE/EE synergies vary by country, with notable reductions in China, Germany, and the United States.

Policy Recommendations

• Develop smart and well-designed initiatives to maximise the synergies of RE/EE across all energy sectors.
• Accelerate the deployment of RE/EE in industrial and transport sectors.
• Explore more ambitious EE solutions in buildings, such as integrated RE/EE systems.
• Plan for long-term energy system improvements beyond 2030, including the development of emerging technologies.
• Expand the scope of countries and technologies studied to enable global conclusions and support the achievement of climate and sustainability targets.

Key Findings

• 90% of the carbon reductions needed to limit global warming to 2°C can be achieved through the combined deployment of RE and EE.
• The Reference Case predicts a 10% increase in global CO₂ emissions by 2030, but with RE/EE, emissions can be significantly reduced.
• In 2030, all five G20 countries show strong synergies between RE and EE, with notable improvements in energy efficiency and renewable energy shares.
• The REmap + EE scenario leads to significant cost savings and reduced emissions compared to the Reference Case, with the most pronounced benefits in China, Germany, and the United States.

Cost-Competitiveness and Economic Benefits

• RE/EE technologies are cost-effective and can lead to overall savings in the energy system.
• The cost of decarbonisation is small compared to the improvement in human welfare through reduced externalities such as air pollution and health impacts.
• Energy efficiency has the potential to reduce energy demand and emissions effectively, while renewables can increase the share of clean energy in the system.

Conclusion

The study highlights that RE and EE must be pursued together to achieve the dual goals of accelerating the renewable energy share and reducing energy intensity. It calls for greater understanding of the potential of RE/EE at the country, sector, and technology levels, as well as policy support to unlock these synergies. The report concludes that RE/EE is the most feasible and timely approach to decarbonising the global energy system.