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©2021 Kimberley Kampers Manufacturing Pty Ltd
Energy System | Battery Charging - Vehicle Set Up
Kimberley recommend a vehicle charging system like this:
To get maximum solar panel performance from a solar array you need the following:
• Full exposure to sun.
• Clean panels.
• Do not shade any part of the panel array. Even small leaves or debris will effect the
effi ciency of the panels.
• When the sun is perpendicular to the panel is when maximum energy will be
harvested.
• Cool temperatures - less than 25°C / 77°F at the solar wafer itself.
Factors reducing maximum performance are:
1. Incident Angle - this is the angle of the sun to the roof on your off-
road caravan. The concept is shown on the right. The degree of
loss depends on the latitude and the time of day. At the best time of
day, the maximum % you can have at these latitudes is: Perth: 84%,
Melbourne: 78% Darwin 97%. As the time of day moves from the
optimum, the % will reduce slowly to zero. Early in the morning and at
4pm in the afternoon, it may be as low as 5%.
2.
Dust on the panels - this just reduces the amount of energy getting through. It is not uncommon to fi nd a
30% reduction because of a solid layer of dust.
3. Shading - for this reason we connect arrays in a way to minimise shading effects and to maximize the
voltage output from the roof array.
The rule is ZERO shadow for maximum performance.
4.
Temperature - the temperature of the solar array has a signifi cant effect. As the surface and cell
temperature rises, the effi ciency of mono-crystalline cells reduces. When the surface temperature hits
65
°C/149
°F , which is the typical temperature in the North of Australia, the output may be reduced by 20-
30% alone.
The compound effect of sun angle, dust and temperature always reduces the output even before shading.
Experience is that 50% of the nominal roof capacity is a workable guide with no shading. This means a 500W
roof based solar array will average 17 amps at peak times with no shading. If you have perfect conditions and
the amount of charge in low, then review the state of charge of the batteries. If the batteries are fully charged,
the solar controller will put very little charge into the batteries. If the batteries are less than 70% charged, then
you will most likely see the maximum available.
Secondly, although the overall system is 12V, the actual solar charge voltage may be as high as 14.5V. So
we do the power calculation of maximum current using 14.5v not 12V. Good MPPT controllers will have 95%
effi ciency. So there are controller losses of around 5%.
Finally when there is shading from cloud cover, the output will vary considerably and the MPPT controller
will be changing the peak charging state based on this. Your trailer is equipped with a dynamic MPPT solar
controller that will rapidly adjust to shading conditions in an attempt to maximize power output. This may be
normal.
Energy System | Solar Panel Operation-Getting Max. Performance
Summary of Contents for KARAVAN 2021
Page 1: ...MAINTENANCE OPERATING MANUAL THE KIMBERLEY KARAVAN Version 160921 2021 ...
Page 23: ...23 2021 Kimberley Kampers Manufacturing Pty Ltd Hitching Up Your Kimberley ...
Page 24: ...24 2021 Kimberley Kampers Manufacturing Pty Ltd Hitching Up Your Kimberley ...
Page 119: ...119 2021 Kimberley Kampers Manufacturing Pty Ltd Notes ...
