住宅用太阳能加热和冷却应用技术简介（英文版）_44页-3mb

Summary of Solar Heating and Cooling for Residential Applications

Core Content

Solar heating and cooling (SHC) systems are renewable energy technologies that convert solar radiation into thermal energy for domestic hot water and space heating/cooling. These systems have been successfully deployed in various countries for over three decades and are becoming increasingly relevant in the context of sustainable energy and climate change mitigation.

Main Points

1. Technology Overview

• Solar thermal systems (STS) are used to generate heat for residential applications by converting solar radiation into thermal energy.
• STS can be used for hot water, space heating, and cooling, and are often integrated with heat exchangers or combined with other technologies like heat pumps or solar PV.
• Two main types of solar collectors are used:
  • Flat-plate solar collectors (FPC): These are widely used, especially in Europe and other parts of the world, and are suitable for a range of temperatures.
  • Evacuated tube solar collectors (ETC): These are more efficient and have lower heat loss, particularly in colder climates, and are increasingly popular in Asia, especially in China.

2. Market Penetration

• STS have achieved high penetration in countries like Cyprus, Israel, and China, where government mandates and subsidies have supported their adoption.
• Globally, only 1.2% of building heating and cooling demand is currently met by solar thermal systems.
• Thermosyphon systems are the most common, accounting for 75% of installed capacity, while pumped systems account for 11%.
• Air collectors for space heating account for less than 1% of the installed capacity.

3. Key Benefits and Applications

• STS can reduce fuel consumption for hot water by 50-70% and for space heating by 30-60% in energy-efficient homes.
• Solar domestic hot water systems are widely used, with systems typically ranging from 3-10 kWth for single-family homes.
• Solar combi-systems combine hot water and space heating, and are gaining traction in Europe, where they can provide up to 60% of a home’s heating and hot water needs.
• Solar cooling systems are still in early stages of deployment but have significant potential, especially in regions with high cooling demands like the Middle East and the Sunbelt.

4. Cost and Efficiency

• The cost of STS varies significantly across countries, influenced by the quality of solar collectors, labor costs, and climate.
• In the US, STS need to be 3-5 times cheaper to be competitive with gas boilers.
• In Europe, especially in Central and Southern Europe, STS are already cheaper than gas and electricity.
• In China, despite a shorter expected life expectancy, STS are more cost-effective than electric or gas water heaters.

5. Challenges

• High upfront costs remain a barrier, especially in developed countries.
• Integration into existing housing is complex and costly.
• Competition with other technologies like heat pumps and solar PV.
• Lack of regulatory frameworks and limited knowledge among professionals and consumers.
• Inconsistent quality assurance across regions, although international standards (ISO) are available.

6. Policy and Deployment

• Government mandates and subsidies have been critical in the successful deployment of STS, especially in new construction.
• Emerging economies are showing strong growth in STS adoption due to increasing energy demand and the need for affordable, sustainable solutions.
• Low-income housing support and district heating systems are new and promising strategies to increase STS deployment.
• International certification schemes are being developed in Latin America and the Arab Region to ensure quality and consistency.

7. Future Developments

• Innovations are focusing on thinner, cheaper, and more durable solar collectors.
• The European Solar Thermal Technology Platform envisions Active Solar Buildings (at least 50% of heating and cooling from solar) becoming a standard by 2020 and reaching 100% by 2030.
• Thermo-chemical heat storage and improved building design will be key to achieving these goals.
• Large solar district heating systems are being developed, with Denmark leading in this area, and have the potential to replace fossil fuel-based systems in urban areas.

Key Information

• Solar thermal systems are mature and widely used in residential applications, especially in warm climates.
• Thermosyphon systems are dominant in the market, while pumped systems are growing in popularity in regions like Europe and Australia.
• ETC are preferred in countries like China and India due to their efficiency and cost-effectiveness.
• Government policies play a crucial role in the adoption of STS, especially in new construction and low-income housing.
• Solar cooling is a growing area with potential to reduce peak electricity demand in regions with high cooling needs.
• District heating systems offer a scalable solution for large-scale solar thermal deployment, especially in urban areas.
• International standards and certification schemes are essential for ensuring quality and promoting wider adoption.