Analysis for Common Problems in Solar Domestic Hot Water System Field-testing in China

Abstract

Abstract China's total urban solar thermal application area has gone up to 2.7 billion square meters by the end of 2013. Domestic solar hot water system, as a main form of solar thermal applications in the building sector, is widely used by city residents. It can substitute conventional energy and meet the residents’ need of domestic hot water,. But how is the practical effect? To get the real results, it needs field-testing or monitoring. In China, field-testing is most common used. At present, through analyzing a large number of actual test data, we discovered that there are some common problems about the indicators and methodologies used in the field-testing. Some indicators do not reflect the purpose of the energy-saving design. Some test data deviates from the normal range of value. After communicated with several large organizations, we identified some difficulties in the actual field-testing, especially some data is hard to monitor. In order to better represent building energy efficiency, and fully address the ability of renewable energy substituting conventional energy, this article make an in-depth analysis of common problems occurred in solar domestic hot water system field-testing to identify short comings based on existing data. The final goal is to identify more effective system field-testing indicators and methods to better reflect the actual results and evaluate solar domestic hot water systems.