This Arduino Nano controlled solar battery charger can charge a standard lead acid 12V battery and runs with 90% efficiency under 70ᵒC (158ᵒF). The circuit can take up to 24V input from the solar panels. The maximum power point tracking is implemented in the circuit by measuring the output voltage and current from the solar panel to get the maximum possible power from it.
Solar battery charge controller - [Link]
Fully Programmable Solar BMS ( Battery Management System ) Learn to program microcontrollers and HW design video tutorials Open Source:
This Battery Management System development board is designed to work with any type of rechargeable Lithium batteries and supercapacitors thanks to fully user programmable parameters.
Whenever you need to use a rechargeable lithium battery you will also require a BMS. Most small device have them integrated like the battery from your laptop, cellphone or cordless power tools (if they use Lithium). Same is true for supercapacitors (EDLC).
Open Source Programmable Solar BMS Li-ion, LiFePO4 dev board - [Link]
In December 2013 Linear Technology announced a new chip – LT8490. This chip includes a 80V Buck-Boost Lead Acid & Lithium Battery Charging Controller that actively finds true Maximum Power Point in solar applications.
No yet available, that chip looks very promising. It operates with input voltages down to 6V and can boost that to charge batteries with higher voltage. I made already a schematic and board design from the preliminary datasheet that charges a 3S LiPo from a solar panel with up to 5A. A small board size allows usage in model gliders with large wing span to charge the battery in flight.
Solar charger with MPPT - [Link]
A solar charge controller regulates the voltage and current coming from your solar panels which is placed between a solar panel and a battery .It is used to maintain the proper charging voltage on the batteries. As the input voltage from the solar panel rises, the charge controller regulates the charge to the batteries preventing any over charging.
Arduino Solar Charge Controller (PWM) - [Link]
The organic solar film producer Heliatek based in Dresden, Germany have announced an improved type of solar cell which gives a transparency of 40 % while achieving 7 % energy conversion efficiency. Although its efficiency is not as good as the company’s opaque organic cells (roughly 12 %) this new solar film can be discreetly integrated into building and vehicular glazing to provide an energy harvesting tinted transparent film. The film is also effective at low light levels and high temperatures where conventional cells lose out.
HeliaFilm uses small molecules (oligomers), developed and synthesized at Heliatek. Oligomers are deposited at low temperatures in a roll-to-roll vacuum process and by changing the spectral absorption properties of the molecules the film can provide different levels of transparency and a colored tint. According to Thibaud Le Séguillon, Heliatek CEO “The transparency of our products is at the core of our market approach. Our HeliaFilm™ is customized to meet our partners’ specific needs, we are a component supplier and this component is a film which can combine transparency and energy generation. This unique combination widens our market potential.”
Organic Solar Film adds Tint and Power - [Link]
by Publitek European Editors:
Monitoring is the key to unlocking the energy production of the solar cell. It is easy to lose efficiency through the use of circuit architectures that assume constant energy production when the solar environment is constantly changing.
The change in current-voltage properties as a solar module heats up or receives more light can be an important source of efficiency losses in solar arrays. If the inverter that generates grid-compatible electricity is not tuned to the output voltage and current conditions, it will waste more of the electricity than it should. In response, electronics companies have produced ICs that perform the maximum power-point tracking (MPPT) needed to optimize energy conversion as well as bypass electronics to prevent temporarily unproductive modules from disrupting the output of active cells.
Maximizing the Output from Solar Modules - [Link]
Researchers Steve Dunn at Queen Mary University and James Durrant at Imperial College London have been experimenting with a new design of thin, flexible solar cell made from zinc oxide. Manufacturing costs of the new cells will be significantly lower than conventional silicon based technology. The only disadvantage is their poor efficiency; just 1.2 %, a fraction of that achievable with silicon.
The material also exhibits piezo-electric properties, nanoscale rods of the material generate electricity when they are subjected to mechanical stresses produced by sound wave pressure. Sound levels as low as 75dB, equivalent to that from an office printer, were shown to improve efficiency. Durrant said “The key for us was that certain frequencies increased the solar cell output, we tried our initial tests with various types of music including pop, rock and classical”. Rock and pop were found to be the most effective. Using a signal generator to produce sounds similar to ambient noise they saw a 50 % increase in efficiency, rising from 1.2 % without sound to 1.8 % with sound.
New Solar Cell Shows a Preference for AC/DC - [Link]
Julian Ilett demonstrates his Arduino Solar Charge Controller. He has mounted all of his Arduino modules to a piece of wood to keep everything nice and neat. [via]
“High efficiency values (96% – 97%) are achievable when the buck converter is stepping down from 18v to 12v. With a 72-cell panel and the converter stepping 35v down to 12v, the efficiency drops to around 88%.”
Arduino Solar Charge Controller - [Link]
A team comprised of the Fraunhofer Institute for Solar Energy Systems, Soitec, CEA-Leti and the Helmholtz Center, Berlin has just unveiled the world’s most efficient solar cell! Boasting an efficiency of 44.7%, the cell breaks the record set by Sharp just three months ago by 0.3%. The four-junction photovoltaic cell is not only dramatically more efficient than the theoretical 33.7% efficiency limit of conventional silicon-based solar PV, but it puts the team well on the road to reaching their goal of 50% efficiency by 2015.
German-French Team Unveils World’s Most Efficient Solar Cell! - [Link]
Graphene is by definition flat and planar, but researchers at Michigan Tech have discovered a manner of fabricating 3-D graphene–a honeycomb structure that can replace the expensive precious metals in solar cells and potentially other energy applications such as batteries and even superconductors. [via]
3D Graphene for Cheaper Solar Cells - [Link]