2005 Volume 67 Issue 2 Pages 100-110
This study developed a power saving greenhouse side window controller driven by photovoltaic energy. Controller operation was tested in a greenhouse during two periods: from 26 April to 26 May 2003 (period A) and from 2 July to 3 August 2003 (period B). Side window opening and shutting temperatures were set at 25°C and 20°C during period A and at 30°C and 25°C during period B. Weather during period A was mostly fair. The daytime temperatures were often higher than 30°C. In contrast, insolation during period B was only 64% that of period A because of the unusually cold summer with less sunshine. The side window controller was moved using power from a combination of an amorphous silicone photovoltaic module of 0.078m2 with rated maximum power of 3.2W and a battery capacity of 28 Ah in 5 hour rate (12V). In both periods A and B, the greenhouse side windows were well operated according to the greenhouse temperature, without outage. The daytime interior temperatures of the greenhouse were concentrated in the range of the side window opening and shutting temperature by operation of the side windows.
