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