Energy Efficiency Made Simple Vol IV 2015

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The two meters at the top right show the instantaneous values. The left meter shows the steered panel output (black on the graph), while the right meter shows the fixed panel output (red on the graph). This was the best of the logging sessions with a virtually cloudless day, with the exception of a disturbance at around 16:21. The reduced final readings were due to trees obscuring the western horizon. For this day we can calculate the percentage gain: Gain = (715,3 – 575,2) X 100/575,2 = 24,36% Earlier sessions produced gains in the region of 20%. The averaging algorithm on the datalogger gave the same result. The values represent the raw result of the datalogger’s 12 bit (0 – 5 V) analog to digital converter. As we were only interested in comparative results, we made no attempt to process the readings. They are, however, proportional to milliamp hours (mAH). Conclusion • Different times of the year will almost certainly give different results. I intend to repeat the experiment around 21 December (summer solstice) for comparison. These data were obtained in late August

• Morning fog and pollution, as well as the oblique angle with respect to the earth’s atmosphere, cause the slow start. In the morning. This could vary by season and location • We are satisfied with our attempt to put some numbers to this concept • Estimated costs for a full size mechanism has not been attempted, as reliability could easily be degraded by conditions such as strong gusts of wind; only a test installation would give answers Acknowledgement I would like to thank my colleagues Andrew Craig and Joseph Jansen for constructing the mechanism. Dedication This article is dedicated to the memory of the late Professor Alan Nurick, a gifted solar experimenter and a good friend.

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ENERGY EFFICIENCY MADE SIMPLE 2015