Build a mini solar tracker

[Villegente]

Hello,

I am looking for a plan and information to build a mini solar tracker.
The goal is to optimize the performance of a small panel that recharges the battery of a solar pump and have fun by tinkering with the system. To be completely sincere, the primary interest is to have fun without breaking the bank.

After some research on the net, I plan to go on a two-axis tracker. Probably a few things based on arduino.
What do you think of the idea of ​​separating the tacker's power supply (a mini panel and its battery) from that of the pump?
The dimensions of the pump panel are approximately 40cm x 25cm. Can you help me to size the tracking system (engine and axes) knowing that the location and at times subject to good gusts of wind?

Thank you for your help.

Have a good day,

[izentrop]

Hello,
There are lots of montages on the net.
The basic assembly http://pybar.fr/index.php?page=tracker 3 photoresistor for 3 D monitoring and 2 servo motors for site and azimuth orientation. Should be added electromagnets for anti wind blocking.
This assembly is very energy consuming. At best, we can save 30% of energy, but we will have to deduct that consumed by the tracker.
Otherwise the easiest way is to buy the panel directly which will capture the additional 30%.

[Gaston]

The difficulty of this type of assembly lies above all in the production of the mechanical part which must be solid, reliable, weather resistant and without (too much) friction.

Wind blocking is not necessarily necessary (in particular with a worm-type actuator).

On the other hand, an anemometer sensor to put the panel in the safety position above a certain wind speed is almost essential ...

The separate power supply of the tracker is not essential, but can be considered (especially if it simplifies the problem when the voltages are different).

[dirk pitt]

servo motors to make a tracker !!!!
waste of energy. whoever spawned it did not think for a second.
a servo motor is dedicated to position control of fast systems.
a solar tracker is slow, very slow, or even very very slow.
changing the setting 4 times an hour is more than enough to gain what there is to gain.
stalling taking a few seconds of engine operation each time.
instead of a permanently powered servo motor ... in position control.

[chatelot16]

all these systems that seek the sun with 2 axes make me laugh ... for centuries we know exactly the movement of the earth and the sun, there is no need to look for it

solution: equatorial mount! a single joint parallel to the earth's axis, and a single motor running at 1 revolution per 24h

if the frame can do the full turn the panel will continue to aim at the sun during the night, aiming across the ground and find itself facing the sun the next morning ... the downside is that it needs rotating contact to connect the panels

solution to avoid rotating contact: reverse rotation at 6 o'clock in the evening, turn inside out at night and return to normal direction at 6 a.m. (solar time, correct with our time difference)

it is more energy efficient to run continuously at a low speed than to have an unnecessarily too powerful motor which runs from time to time

so a large number of gears are needed to make the right reduction, and thanks to this reduction a very small motor is enough

it may be necessary to seek the sun exactly for a parabolic concentration sensor, but for an ordinary photovoltaic panel to start the rotation at a fixed point and at a precise time is largely sufficient

[Gaston]

all these systems that seek the sun with 2 axes make me laugh ... for centuries we know exactly the movement of the earth and the sun, there is no need to look for it

The tracker is a little more complex, but it has the advantage of not requiring any adjustment: after a stop (a safety lockout due to a storm for example), it is enough to restart it without the need to know what time of day or night it restarts.

solution: equatorial mount! a single joint parallel to the earth's axis, and a single motor running at 1 revolution per 24h

Unless I am mistaken, the equatorial mount is equivalent to a 1-axis tracker.
It compensates for the daily rotation but does not automatically compensate for the seasonal variation in height of the sun.
The orientation is not entirely optimal, but for a solar panel it may be sufficient (you can also manually change the incline at each change of season).

[izentrop]

servo motors to make a tracker !!!!
waste of energy. whoever spawned it did not think for a second.
a servo motor is dedicated to position control of fast systems.
a solar tracker is slow, very slow, or even very very slow.
changing the setting 4 times an hour is more than enough to gain what there is to gain.
stalling taking a few seconds of engine operation each time.
instead of a permanently powered servo motor ... in position control.

We can decide everything with a circuit like the arduino, picaxe or other automaton, like choosing to set only 4 times the hour and only supply it at these brief times. All this with very low consumption thanks to the economizer mode. You can even reduce the clock frequency.
A few instructions in C C + language and voila.
On the financial side, there are 10 kg / cm servos at less than 4 roros and even cheaper pro mini.
http://www.electronicoscaldas.com/datas ... er-Pro.pdf We can count on a consumption of 0.01 wh / day for 4 repositioning per hour.

[dirk pitt]

With a servo motor, you have to drive all the time: servo in position otherwise the panel can turn under the action of the wind or its own weight. the mechanics of a servo motor are reversible.
you can only drive at regular intervals if you have an irreversible positioner. for example a worm / wheel system.

[izentrop]

For blocking, I thought of an electromagnet which unlocks the mechanics at each repositioning.

[chatelot16]

with an equatorial mount you can adjust manually to adapt to the height of the sun ... once a month is already much more precise than a tracker which does not work permanently but once or twice an hour

so manual height adjustment once a month, and rotation at constant speed starting at a fixed time .... return to the end of the race overnight .... to be sure that the return to the end of the race takes place that the direction reversal time be a little before 6 p.m. solar time

so it makes a very simple automation ... whether it is done by an arduino another microcontroller or an even simpler automation is an unimportant question

if the automation is done by an electromechanical programmer it risks consuming almost as much as the motor which turns the panel ... because quue to make turn with a reduction which makes 1 t / 24h it is not necessary a large motor but just a scheduler engine