Review of Solar Water Heaters with Integrated Collector-Storage Units

摘要

The integrated collector-storage (ICS) solar water heater is one of the simplest applications of solar energy for water heating. In an ICS solar water heater the collection of solar energy and the storage of hot water occur in a single unit. The ICS solar water heater has been demonstrated to operate consistently and reliably for many years with a small initial investment relative to other solar water heater designs. However, the ICS solar water heater is not very efficient for overnight applications and its thermal output diminishes sharply as the time increases between solar energy collection and use. To make the ICS solar water heater a more economically viable option, the system has evolved, utilizing new research advances to maximise solar radiation collection and minimise thermal losses as much as can be reasonably accomplished. In this article, the concepts, designs and applications of integrated collector-storage solar water heaters are reviewed, focusing on state-of-the-art and recent developments. Also described are descriptions of new designs, enhancement methods for solar energy collection and strategies used to reduce thermal losses, environmental impact, test methodologies and barriers and constraints affecting the acceptance and adoption of integrated solar water heaters.