Concentration solar collectors for solar heating plants

Background

Buildings consumes up to 40% of national total energy consumption in the developed countries, while in China about 20% of national energy consumption is used for buildings. In recent years, with rapid expansion of city area and high-speed urbanization, the proportion will undoubtedly increase. However, Sino-US Climate Declaration was announced at APEC, 2014.That carbon emissions peaks before 2030 has been promised by the Chinese government. Building sector should not be ignored. For China, energy consumption of heating in northern region has taken up 25% of total building energy consumption currently. Therefore, improving the application of renewable and clean energy-solar energy in buildings, reducing building energy consumption, is a key to solve energy and environment problems. China has the largest solar thermal application market all around the world. However, most of solar market in China focused on Solar domestic hot water system. Large scale solar district heating system is very rare in China. There are enormous market potential for solar district heating plants in China.
Denmark is well known for successful application of large scale solar district heating plants. High performance collectors are the core components of the solar heating plants. And majority of the solar heating plants in Denmark use flat plate solar collectors nowadays. Due to higher collector heat losses, efficiency of flat plate solar collector will be significantly lower at the operation temperature of 85°C-95°C compared to the efficiency at a temperature of 40°C-60°C. While concentrating solar power (CSP) collector typically has a lower heat loss coefficient and is less affected by operation temperatures of the collector, CSP collector can be used with advantages in district heating plants operated at a temperature as high as 85°C-95°C.It is worth doing research to validate the feasibility of CSP collector for large scale solar heating plants.

Arrangements

CSP performance calculation model will be developed: development of a strong and reliable calculation model with and without combination with flat panels for different orientation of the CSP plant. The model will be able to handle the options with and without seasonal storage as well as with and without an accumulator tank. The impact from the consumers demand will also be included. The dynamic simulation is required to evaluate as accurate as possible the highly variable behavior of the solar heating plant system during the day and along the year.
A large scale demonstration solar heating plant with both a CSP collector field and a flat plate solar collector field will be monitored. Performance between actual and predicted performance will be analyzed. Simulation models will be validated and used to optimize these integrated systems.
Profitability of combined flat panels and CSP technologies will also be discussed eventually.

Expected goals

The aim of the project is to research and demonstrate the advantages and disadvantages of CSP collector for production of heat for district heating plants. The result of the project could be relevant for solar heating plants, solar collector manufacturers, and decision maker both in Denmark and China. Successful implementation of the project will strengthen the already existing Sino-Danish research cooperation in the field of solar scale district heating and introduce solar district heating technology to China, especially northern China.