Photovoltaic category

Using a supercapacitor for power management and energy storage with a small solar cell

& @ writes:

In Part 1 of this series, we have reviewed solar cell performance, how to select and size the supercapacitor, requirements of supercapacitor charging circuits and charging IC characteristics. We will now use two case studies to illustrate these properties in detail.

Using a supercapacitor for power management and energy storage with a small solar cell – [Link]

MPPT solar charger

Lukas Fässler from Soldernerd has been working on revised version of his MPPT Solar charger project:

Over the last few weeks I have been quite busy with my MPPT Solar Charger project. I’ve built up a first board and started writing firmware for it. Since the last version was not too different in terms of hardware I was able to re-use most of that code. But I hadn’t even touched on the whole USB stuff back then so there was still a lot of work to do. While the project is still far from being complete I am happy to say that I’ve made quite some progress. Most importantly, the new design seems to work well and so far I haven’t found any mistakes in the board layout. But let’s go through this step by step.

MPPT solar charger – [Link]

BQ25504 Solar Cell LiPo Charger

by Pesky Products @

This is a small (0.5 x 0.5 inch) breakout board for Texas Instrument’s BQ25504 Ultra Low Power Boost Converter with Battery Management for Energy Harvesting Applications.

BQ25504 Solar Cell LiPo Charger – [Link]


Circuit implements photovoltaic-module simulator


José M Blanes and Ausiàs Garrigós writes:

Electronics engineers often use photovoltaic-module simulators to test dc/dc-power converters, inverters, or MPPT (maximum-power-point-tracking)-control techniques. The use of these simulators lets you work in the laboratory with predefined photovoltaic conditions, thus avoiding the drawbacks of real photovoltaic modules. Various commercial simulators are available, but they are often expensive.

Circuit implements photovoltaic-module simulator – [Link]

How to connect a Solar Inverter in 10 minutes

Let’s connect a solar power inverter for AC voltage output in just 10 minutes.

How to connect a Solar Inverter in 10 minutes – [Link]

Arduino based sun tracking turret

Arduino Based Sun Tracker Turret

Sun tracker systems are widely used in solar panel setups to get maximum performance. You may want to use one in your personal solar panel setup. Now you can make your own with an Arduino, following the project that’s designed by RobotGeek Team and Wade Filewich.

Arduino based sun tracking turret
Arduino based sun tracking turret

Parts You’ll Need:

You should also upload the sketch in Arduino. So download it from GitHub –> desktopRoboTurretV3.

To upload the sketch in Arduino,

File → Sketchbook → desktopRoboTurretV3 → roboTurret3_solarTracker

Now click Upload.


Sun Tracker Turret Based On Arduino
Sun Tracker Turret Based On Arduino

Place the light sensors in correct position and wire them to Arduino accordingly. Any wrong positioning can generate strange behavior of the system.  Jumpers for the servos (pin 9, 10, and 11) are set to VIN, so that your servos function properly.

(NOTE: A 6V power supply will work just fine, and RoboTurret Kit includes one). Here is the chart of wiring:

Wiring list of servo and Arduino : Sun tracker
Wiring chart of servo,light sensor, potentiometer and Arduino : Sun tracker

There are two potentiometers. One is for controlling the speed of servos, and another is for controlling the sensitivity of sensors.

Set Up The Turret:

You should follow Desktop RoboTurret Assembly Guide to build the turret. After building, attach your sensors to the top plates as close to center as possible. Look at the picture:

Sensor Positions On Turret
Sensor Positions On Turret

The “+” shaped fins cast shadow on sensors. So, position of sensors should be correct else fins can’t cast shadow  on them accurately. Have a close view on sensor’s position:

Sensor position on turret : close lookup
Sensor position on turret : close view

While wiring through the plate, keep wires loose enough so that turret can move freely to aim at the Sun. At the back of the turret base, there is plenty of room to mount the two potentiometers.

The fins are 8 inches tall, which should be plenty to cast shadow on the sensors. I’ve used scrap cardboard for the fins, but you can use whatever material suits you best, so long as it is opaque and can throw a shadow.

Test It:

So, you finished the building process. Now let’s test it. Upload the code to Arduino and power up the system. Now hold a table lamp and move it. The turret should follow the movement. Adjust speed and sensitivity using the two potentiometers. Watch the video that demonstrates the system:

MPPT solar charger


Lukas Fässler show us his progress on the MPPT solar charger:

One of my main goals with this design is to achieve very low standby current, somewhere in the tens of microamps. The basis for this is a low-power buck on the basis of a Texas TPS62120 where the microcontroller can switch the output voltage between 2.2 and 3.3 volts nominally. This works as intended. With no load and the output voltage low, the supply consumes 12.9 microamps at 12V input voltage. With the high output voltage the idle current goes up to 14.3uA. Quite a bit of that current is due to the voltage divider that sets the output voltage. The regulator itself consumes about 9uA in both cases.

MPPT solar charger – [Link]

A very simple DIY solar-powered USB charger


Raj @ tipped us with his latest project. It’s a simple, but useful USB Solar powered charger able to charge a power bank or your smartphone.

Yesterday, I built a very simple DIY solar-powered USB charger for my TP-link 10400mAh USB Power Bank. All I needed was a 6V/3.5W solar panel and the TD1410-based 5V buck converter module. I bought both of them on Aliexpress for less than $8.

A very simple DIY solar-powered USB charger – [Link]

MPPT Solar Charger Design based on PIC18F26J50


At the core of the design is a PIC18F26J50 in a 28 pin SOIC package. It’s capable of running at down to 2.15 volts and consumes extremely little power when running at lower clock speeds. And apart from that it features USB so we can have all the benefits of USB without any external components except, of course, a USB socket.

MPPT Solar Charger Design based on  [Link]

Photovoltaic simulator system adds automated MPPT Efficiency Test


An added test facility enables test of a 1,500V photovoltaic (solar energy) inverter’s static and dynamic maximum peak power tracking (MPPT) according to European Standard EN50530, with a single command, creating downloadable photovoltaic I-V curves, plus static and dynamic EN50530 test reports. by Graham Prophet @

Photovoltaic simulator system adds automated MPPT Efficiency Test – [Link]