Research and reports

Investment in solar water heating systems for commercial applications is often constrained due to a shortage of investment capital. Yet commercial enterprises such as hotels, motels, restaurants, food processors and food take-away outlets may use large volumes of hot water that could make the economics of investment in solar water heating systems attractive if the capital cost could be modified to be an operating cost.

Prior to 2008 Cashmere High School was heated by two coal fired boilers. These boilers had reached the end of their economic life and the schools discharge consent for coal firing was soon to expire. Cashmere High School needed to seek a clean heating alternative. Wood pellet boilers were selected by the school as being the best alternative to coal and a pair of wood pellet boilers were installed in 2008. This monitoring report contains data collected from the first year of the boilers operation.

The Landcare Research space heating is currently derived from coal boilers that are located at the Crop and Food facility. The desire to pursue a carbon neutral fuel that is in line with their policy, along with improving the level of heating that is currently available from the
current system, are the key drivers for this feasibility study.

With the assistance of the Innovation Fund, Wellingtonian Stuart Dickson has developed an integrated unglazed solar water heating system that makes innovative use of thermal storage and a heat pump to provide space and water heating. The prototype system was designed and tested using his own house and garage as the testing site, so Stuart has had real-time feedback on how the system is operating.