#142

In this video, I will start a project to use solar energy to power ESP8266 or Arduino devices during the whole year.
We wll answer the following questions:
1. What size the solar panel has to be in order to power our device
2. What size of battery we need to survive times with less or without sun?
Links:
Solar panels:
Solar Panel 165x165mm s.click.aliexpr...
Solar Panel 112x84mm s.click.aliexpr...
Solar Panel 53 x 30mm bit.ly/2shHVRJ
Solar Panel 86 x 38mm bit.ly/2szAvwk
Solar Panel 107 x 61mm bit.ly/2szn7rN
Solar Panel 99 x 69mm bit.ly/2shEDho
Solar Panel 80 x 80mm bit.ly/2rCsMsq
Solar Panel 540mm x 340mm s.click.aliexpr...
Power Meters: bit.ly/2x5rVEm
Results: docs.google.co...
solargis.com/m...
solarelectricit...
www.timeanddat...
Supporting Material and Blog Page: www.sensorsiot.org
Github: www.github.com...
If you want to support the channel and buy from Banggood use this link to start your shopping: bit.ly/2jAQEf4 (no additional charges for you)
/ sensorsiot
/ spiessa

[@hianandm]

sir, you have summarized the learning of multiple weeks to minutes . great video

[@AndreasSpiess]

Thanks!

[@andriizakharov2386]

Hello Andreas, just discovered your channel. How great it is that you are giving all this theoretical background before trying to build something. This is what more people should do. Good work, subscribed.

[@AndreasSpiess]

Welcome to the channel!

[@MikeKranidis]

Very informative and well organized video. Thanks Andreas for the offering!

[@AndreasSpiess]

You are welcome!

[@joshuarosen6242]

I have almost certainly watched this video before but I didn't have any specific interest in solar power then. Now I do and I searched your channel for a video on exactly this topic. As is so often the case, your video gave me exactly the information I needed, avoided unnecessary and irrelevant detail and explained everything clearly. As we say in England, it was spot on. Thank you.

[@AndreasSpiess]

Glad it was helpful! I try to produce the videos with my most important questions in mind...

[@takeyoshix]

"Because this is boring we do some tests outside..."... Cool, wirklich nicht schlecht eingebaut. Der Beitrag war aber so oder so sehr belehrend, vor allem die Fakten über die Sonneneinstrahlung und wieviel Energie man nun effektiv abzapfen kann. Besten Dank.

[@AndreasSpiess]

Gern geschehen!

[@thomasbauer5663]

Ja ist denn schon wieder Sonntag :-). Vielen Dank Andreas für die sehr gut strukturierte Vorgehensweise, sowie Deinen Berechnungen und Erklärungen. Freue mich schon auf die Fortsetzung... :-)

[@AndreasSpiess]

Bitte, gern geschehen!

[@daves3819]

Great video, thanks. I've been running an ESP-07 (all LED's removed) for more than a year now here on the Prairies in Canada where temperatures during the winter drop quite often below -35C. I used trial and error to figure out how long to put the ESP to sleep such that it wouldn't kill the battery during a worse case winter scenario. I will have to watch your video again and then apply these new learnings to see how much margin I was playing with. :) I am using a 1800mAh Li-on battery from a Sony PS3 Controller (rated at max charging current of 400mA and max charging voltage of 4.2 volts) and a 5V- 200mW 4.3cm X 3.4cm solar panel. When I tested the solar panel the maximum voltage I could get was 40mA and about 4.5V so I took a chance and connected it directly to the battery (so far so good and it's been more than a year!). I use only a diode to drop the voltage to the ESP and it has never gone above 3.4V. The ESP is on a 200s sleep cycle. As I said it has been working flawlessly for over a year but tomorrow I want to run this through your math. Thanks again for another wonderful and informative tutorial!

[@AndreasSpiess]

Thank you for your feedback. I think, physical laws are similar, even in the Prairies;-) Maybe this page helps for calculation of the power requirements of your ESP: battery-life.of-things.de/battery-life-calculator.php

[@lammingmik]

Andreas, Your videos, and this one in particular, is excellent. Pitched at just the right pace, and level for me anyway. I like the structure, and the order. These are some of the most informative, and useful, videos I have seen. Grateful thanks from SanFran.

[@AndreasSpiess]

Thank you for your nice words! Nice city, BTW.

[@stalbaum]

Super useful. I need to work through the maths for my scenarios. Andreas you are a national treasure for, probably Switzerland, but where ever, most excellent.

[@AndreasSpiess]

Happy to help!

[@frankschmidt5319]

Hi Andreas, first thanks a lot for all the good videos! For a cheap MPP tracker I can recommend a simple TP 4056 Lipo charging board. My setup works as follows: 5V Solar Panel, the charging board (w/ cell protection) and a LiPo battery. As long as the light is very dim, the voltage from the panel is too low for the charging board and no current flows. When there’s more light, the PV voltage climbs over the battery voltage and the charging board starts to charge the battery. If the charging current is too high, the PV voltage drops and so does the current - the PV voltage can climb again. So the charge controller will always keep the PV voltage at the point where it can draw the maximum power from the panel. Two things have to be taken care of: - . - To keep the system from oscillating, I put a capacitor parallel to the panel- The maximum input voltage of the TP4056 is 8V. When the battery is fully charged, no more current is drawn from the panel and the PV voltage will rise to the open circuit voltage. This should not be higher than these 8V

[@AndreasSpiess]

+Frank Schmidt Sounds very promising... have to try it. Thanks for the tip!

[@4.0.4]

This is my favorite video of yours to date. The fact that someone was kind enough to translate it to Portuguese also means I can scare my father (who thinks solar panels probably aren't much harder than connecting panel, battery and an LED lamp in parallel) all under the guise of a friendly 15min video. Not gonna lie I still don't get why MPPT is a $100 device instead of a little board that you buy in packs of 50.

[@AndreasSpiess]

Thanks for the nice words!

[@MrBlade2021]

"In the middle I had to stop to drink a beer". This made my day! I really enjoy your videos/tutorials. They are always very informative and full of very useful knowledge as well as great results. Thanks for sharing!

[@AndreasSpiess]

You are welcome. And I am only a mere mortal ;-)

[@cosmopolitans9354]

One of the best explanation in the whole youtube. Giving easy explanations to easy concept is an uncommon skill. This is real engineering: i'm sure the beer helps! Greetings from Italy

[@AndreasSpiess]

Thank you very much for your nice words. I just returned from a trip to Italy. It is a beautiful country

[@adabill295]

Like your videos. They always start out with what you are trying to solve. That is very important. i often get lost in the weeds and forget about the original intent. I often don't need the projects you are working on BUT I always listen to learn. Great teacher!

[@AndreasSpiess]

Thank you!

[@mt-qc2qh]

Andreas, your videos just keep getting better!! Great info and fun.

[@AndreasSpiess]

:-)

[@craiglarson6793]

Fantastic! It is as if you could see that I was experimenting with a solar panel and Li-On battery today & yesterday way on the other side of the planet. Plus I was trying to calculate panel and cell sizing too. Perfect timing and great spot-on content. Thanks. AND tomorrow is the Summer Solstice - optimal conditions for experimenting. I'm addicted to your videos.

[@AndreasSpiess]

This is the power of the internet, and English as a global language, I think. Really a beautiful world (at least, this part)...

[@TheRainHarvester]

😮how could i use solar only no battery? "On" to Brown out causes a hang .

[@ReflectingMe2024]

Andreas, I really enjoy your videos, you obviously put a lot of thought into their structure and order. This makes for some outstandingly informative stuff!!! Many thanks from this very grateful Welshman.

[@AndreasSpiess]

You are welcome. And thank you for your nice words!

[@MartinBgelund]

Thank you for yet another interesting video. Some things you might want to look into, if you don't get the expected efficiency are: Angle of the panel (I noticed your panel laid flat on the table, which is not optimal), and temperature (cool panels are more efficient than hot panels).

[@AndreasSpiess]

I tried with various angles, but did not get big differences (maybe because it is summer and I did the measurements in the early afternoon. Then, I took the easy(flat) way. But you are absolutely right concerning the angle. If you have a close look at the diagrams in the video, you see the optimal angle for a whole year. Concerning temperature I cannot do a lot, I think, because the place is defined by the purpose. But, because the most critical time is anyway in December/January, the temperature maybe is not a big issue (in summer, I will have too much energy).

[@AndreasSpiess]

Now I remember. I will have a look at it. Thanks for the tip!

[@cristiano.sulzbach]

Thank You for your time. I was also making some tests. Here we have more sun. 10W 5V panel + TP4506 + one 18650 + ESP8266 with deep sleep. Not that efficient but is working well so far. Looking forward for the next video.

[@AndreasSpiess]

+Cristiano Sulzbach Thanks for your feedback. I will try the TP4506.

[@MaxintRD]

Cool, great topic! Interesting info and very informative video! I have a solar-powered network node laying in my window sill for about a year now. It's a 6V 1W panel connected to a ESP-07 module via a 650 mAh li-ion battery with a charger/protection module. It wakes up for ten seconds every 15 minutes, day and night. It survived summer, but stopped in the winter because it didn't get enough sun. It's only for testing/learning now, but in the future I want to make a solar-powered node for my automated garden project, so plenty work left.

[@AndreasSpiess]

Thanks for the info. Maybe you make the calculations I did for your device and compare the results. Then, we would already have one confirmation (or not) of the theory...

[@abhijitborah]

A trivial typo at 2:15 minutes into the video. "×" used instead of "=". Your video has read "the question" in the minds of so many and answered excellently. Congratulations and thank you.

[@AndreasSpiess]

You are right! But unfortunately, I cannot correct it anymore...

[@hoodafukisalice]

Andreas has made science out of what I would have done by trial and error. That is some research!

[@AndreasSpiess]

I also use trial and especially error a lot. But hidden from the channel ;-)

[@artbecker5618]

I look forward to your controller video. Many of them have a USB connector. They claim up to 5V @ 2A, which is enough to power a Raspberry Pi 3. Of course there is no need to start a discussion on how big the batteries would need to be for that application, since we are talking about an ESP8266 & 18650 batteries. Possibly/probably a small single board controller would be sufficient. I'm now going to watch your video #64 again, about batteries appropriate for the ESP8266. Thanks for your videos.

[@AndreasSpiess]

I think, we also can power a Raspberry Pi. The same formulas would apply, just the panel and the battery would be bigger (about 3 times). And i do not know of a "sleep mode" for the Raspberry

[@sruizvargasp3]

Simply excellent. By the way, I wonder about the reason why there are people who have voted 'I do not like'And I live in Spain,... you can imagine that we have sun, sun and sun

[@AndreasSpiess]

Nobody really knows anything about the "don't like" voters...

[@DaveMody]

I'm doing something similar. I switched from the ESP8266 to the ESP32 so I can more easily monitor battery voltage and sensor voltages. One thing I noticed though was that the MPP charge controllers are expensive. So expensive, I just opted to buy more solar cells, which are comparatively cheap, and use a TP.4056 charge module (very cheap) It would have been a better idea for me to have done a proper economic analysis though. Looking forward to your analysis! Keep up the great work!

[@AndreasSpiess]

The TP.4056 was suggested by other viewers, too. So, I will include it into my investigations.

[@DaveMody]

Here's a graph of the past few days of data logging to google docs. You'll notice gaps in data which is when my ESP32 has been hanging and causing my battery to drain completely. I hope I've solved the problem, but I've found the sample code for things like the DS18B20, Wifi connections, and so forth need some improving. Unless you have some good watch dog timers, you need to make sure your code is really bulletproof. docs.google.com/spreadsheets/d/1ni20axRWzek2f--lTF_YY7c1_GgZjzM9ziM6vrI6V38/pubchart?oid=108740660&format=interactive

[@JEL960]

Thank you. I have been looking at videos with similar content for the past few days and I yours has been the most helpful. I hope you continue to provide more. Wish I could give you two thumbs up

[@AndreasSpiess]

Glad it was helpful!

[@deangreenhough3479]

Oh Andreas😀 A superb video, full of useful information and there is going to be a follow up too🙏 It's wonderful that you explain the math and importantly your thought process. I believe you managed to link together a number of things that I thought I understood. So very happy to see things more clearly. As always I am very appreciative of your time and efforts and just how concise you are. The project I am about to start is solar 2 axis for a 160 x 160 solar panel. So this is a great help. Bless you Andreas 👐

[@AndreasSpiess]

Thanks, Dean. Änd of course, we are interested in the results of your project, especially the efficiency (more energy because of good positioning vs energy consumption of motors)!

[@deangreenhough3479]

Andreas Spiess noted thank you. I will set up another INA219 to monitor the motor power requirements and as you say, work out the efficiency. From my research you only need to be within + or - 5 degrees. You will still be 99.6% efficient within this range. So had planned to only adjust at 6 degrees. I assume this is what you were reminding me to think about? Many thanks

[@TishSerg]

5 years have elapsed. What is your experience with the subject?

[@Datlaai1]

​@@TishSerg solar big size

[@manickn6819]

Great video. Really simple common sense calculations. I think anyone dabbling should be able to figure out this themselves but if not you would have helped. What I like best about your channel is the clear straight engineering without any BS. No lies or faked stuff. Too much of the internet and social media is being invaded by persons peddling fake information. Please do keep up the good work. I will keep watching.

[@AndreasSpiess]

Thanks for your support!

[@NerdCoding]

Great informative video, I was hoping this would cover the circuits needed to charge and regulate the voltage to 5v and 3.3v but still a great video

[@nicklaspersson4687]

There is certainly are lot of issues to consider about solar tech. Sadly more often than not the green desire and market hype clouds peoples judgement when investing in solar as the infamous "solar roadways" and Dave Jones have shown. One thing often not mentioned is how the solar panel heats up when exposed to the sun. The efficiency is affected by the panels temperature. If they are incorrectly mounted on a stone tile roof for example the stone tiles with high thermal mass storage capacity might also help heat up and prevent them from cooling. Another thing is the panels angle to the sun. Most often they get fix mounted. Solar tracking is expensive but might be how the supplier calculate their yield. Furthermore there are always losses when using converters. Storing the energy also mostly entails converting and self discharge losses. And then there is the matter of distributing the energy. Keeping them clean from snow and dust and wet leaf is also something that is often ignored. Thank you Andreas for your excellent video that 'shines light' on some of the issues with solar tech.

[@AndreasSpiess]

I think, there are two distinct solar applications: One is to use solar to get maximum energy out. This is where you find a lot of information. And your issue is also located in this application (btw: look for a comment in this video where a viewer reports, that he looses 20% in hot situations) The other application is the one I try to deal with: Get enough energy during the whole year. Here, We have to solve other problems like efficiency in low power conditions, deal with low voltage panels etc. Here, I did not find a lot of information. And heat is not so important, because we anyway will have too much energy in summer.

[@peterl1699]

Great tutorial. This open up so many applications. Im more I treated in the charging units. If there is bigger, smaller and also if you can order them online

[@AndreasSpiess]

So, you have to be patience till I learned enough about that topic...

[@Shaq2k]

Excellent. But this deserves a new 2021 version. I'm sure a lot has changed in 4 years.

[@AndreasSpiess]

Good idea! Recently, I did a video about the topic. Maybe you watch it (if not done already).

[@PhilXavierSierraJones]

Composite systems are quite good at this implementation; There are two power sources, one is solar and one is backup power from the mains electricity. It works just like you expect when conditions are alright; charge the battery in daytime and use it in nighttime. But when solar panel voltage drops too much and battery voltage is below threshold, the device turns to backup power so the device doesn't die.

[@AndreasSpiess]

To have grid power is always a good thing and reduces the size/cost of a project considerably. But for me, I want a completely independent device. So, unfortunately, I have to go the hard way (or change where I live...)

[@bayram4ik]

Thanks for the calculations! You saved me months of learning! Greetings from Turkey!

[@AndreasSpiess]

You are welcome!

[@Ed19601]

ofcourse you made no error in your calculation. You are Swiss. Also, a very clear explanation of the MPP

[@AndreasSpiess]

If I remember school, this was not always the case ;-)

[@Ed19601]

Andreas Spiess yes, but that's were your Swissness was honed and polished :-)

[@kora2111]

Nice explanation. But an additional factor that has to be concidered depending on location ist the dust! E.g. in Dubai the solar panel would get dirty/dusty after some time and thus convert less energy. This can happen without a dusty desert ... some air polution + dirty rain or snow can destroy the calculation also.

[@AndreasSpiess]

You are right.

[@shaunwhiteley3544]

Had to stop for a beer! 😂 classic! 😀

[@AndreasSpiess]

The pure truth!

[@RobiBue]

Ha! Just saw this today :-) Es Locher Bier! Quöllfrisch! Prost bigoscht! Greetings from a Dibidäbi i de Staate ;-)

[@terroshak]

Hi Andreas, very interesting topic as always. Your main concern should be the min max temperatures which the device (including charging and battery modules) will "suffer". Chemical batteries most likely loose as much as 70% capacity when cold until they refuse to charge at all. Also due to reduced molecule movement the voltage is reduced when the battery is connected to small loads (few mA). also batteries can be permanently damaged when they get too hot (fast charging and heat from the sun). Think about the Rosetta Research Lander which suffered those problems on the comet it landed on, somewhat extreme example but you will experience similar problems. Lead gel batteries also often used for off the grid solar systems are best but very bulky... when reducing the max load and total power consumption a powercap can be used.

[@AndreasSpiess]

Thank you for your input. You are right, batteries (and temperature) are an additional issue we have to consider. Another possibility could be to use a big solar panel and super caps. We will see...

[@neslin99]

Thank you! Very interesting. I've been thinking of doing some solar energy experiments myself, sadly northern Sweden is lacking in sun hours most of the year. :)

[@AndreasSpiess]

Maybe you still do the calculations... The difference between Dubai and Switzerland also was smaller than I thought...

[@garethwoodall577]

Very useful and interesting! You deserve them beers on a hot day sir!

[@AndreasSpiess]

Thank you kindly!

[@hypercrack9262]

Thanks a Lot Andreas! If I ever get a chance to come to Basel, I'll definitely drop by!

[@AndreasSpiess]

Cool!

[@W0Ndr3y]

Awesome video. I would only start from the other end. You know how many days/hours you need to run the device from a battery, then calculate the size of solar panel. If you need a week of battery life and power consumption of your device, you have a size of a battery. Then you can calculate size of solar panel to charge the battery within a day or two

[@AndreasSpiess]

I think you can do that with the information given.

[@W0Ndr3y]

@@AndreasSpiess thanks for the reply. Would you consider using solar to power up motors? I would love to do rover-like robot. Or powering such device from solar is not feasible?

[@KENT0070]

Sir, since discover your channel, I like it very much and with your kind guidance, I learn a lot!!!! Thank you very much.

[@AndreasSpiess]

Welcome aboard the channel!

[@ShahabIntezari]

Hi Andreas, the charging unit is very important part of this project I guess. I can't wait to watch your video on that. Thank you

[@AndreasSpiess]

You are welcome!

[@benfletcher7209]

As always a great and instructive video, I don't know how you find the time but am really glad that you do

[@AndreasSpiess]

Thanks!

[@rodrigolima661]

Very good. Very very good. I live in Brasil, Mato Grosso state, very warm and have very sun, and was thinking about and esp8266 for solar weather station, and this video will help me very much, thank you!

[@AndreasSpiess]

So, the results of your calculation will be completely different to mine ;-)

[@rodrigolima661]

yes, but rules are same, and tips are usefull (don't too low voltage battery, thing about bad weather, etc).

[@fuzzie4755]

I have ordered some TP4056 from AliExpress. These connects great to the 18650 battery and deliver the right start and stop for charging. Additionally these are incredible cheap. Looking forward to get them delivered. If they support the MPP I do not know. I assume not.

[@AndreasSpiess]

They are great, but do not support MPPT They are more for normal charging.

[@Msc7532]

Thank you Andreas, I was smiling a lot watching this video.

[@AndreasSpiess]

Thanks! The world is unsmiling enough. So, at least, our hobby should be different...

[@alanmcoll101]

I agree with the positive comments. You are an excellent tutor. Thanks for your efforts.

[@AndreasSpiess]

+Alan Collins :-)

[@paulmacgiollacaoine8619]

Looking forward very much to the next video especially cutting off charging the battery at 4.2v and at the low voltage point. This should solve issues I've been having using the piZero and the sparkfun sunny buddy MPPT controller.

[@AndreasSpiess]

We will see how I will solve these issues...

[@ardisd01]

Andreas very useful video. I have been trying to do a similar thing for my esp8266 could not decide on a charge controller. Looking forward to the next episode.

[@AndreasSpiess]

Which controllers were in your selection?

[@ardisd01]

Sunny Buddy - MPPT Solar Charger from sparkfun and Adafruit USB / DC / Solar Lithium Ion/Polymer charger - v2 both quite expensive and then there was also this one thepihut.com/products/solar-lipo-charger-3-7v?ref=isp_rel_prd&isp_ref_pos=4

[@pepper669]

Very infomative and entertaining at the same time. I see a good use for a INA219 I2C module to measure voltage/current...

[@AndreasSpiess]

I think too, that it could be an interesting part. But I also think (or fear), that we have to keep the number of parts as low as possible because they will use energy all the time, also when there is no sun...

[@pepper669]

Maybe one could switch it on only when needed.

[@AndreasSpiess]

I think, this is a good idea. Maybe even for the whole charger...

[@kalamatagames2631]

mini solar produce constant power you can use( buck converter) or( boost converter) first then you storage power to battery . the milliamps and voltage change all the time when you produce power and you can change it at any ratio you like , to make it more efficient.

[@pablogonzalezrobles4429]

Buck and boost can replace the solar panel controlller?

[@np32sc]

Good technical information. Quite thorough and incisive. I look forward to the next video.

[@AndreasSpiess]

Thanks!

[@vis2020]

Very good analysis. I tried using 3W Poly crystalline panel in India to power the NODEMCU without a battery (using a voltage regulator) but wasn't successful. Can't wait for your next video to see your Battery size recommendation..thank you

[@AndreasSpiess]

Battery recommendations are already in this video. The next will focus on charging the batteries.

[@vis2020]

Andreas Spiess yes, got it thanks..will watch out for next video on how to charge..will it be a charge controller or charging module for LiPo..will wait and see

[@zuraweb]

Complimenti!Spiegazione Chiara ed esaustiva

[@AndreasSpiess]

Grazie!

[@daveblackmoto]

Exactly what I was looking for. Thank you!

[@AndreasSpiess]

You are welcome!

[@chuxxsss]

Sounds like you need the turbine I am doing. Please cover electronic loads I'm rusty and need one for the turbine. Great video too, the solar powered ESP is the way to go.

[@AndreasSpiess]

Your turbine or your summer, which would fit perfectly into our winter.I plan two different videos about two electronic loads. One about my new IT8512A+ and another one as a surprise...

[@AdityaMehendale]

Wonderful narrative style, Andreas!

[@AndreasSpiess]

Thanks!

[@murrij]

This is awesome. thank you for producing this video. I learned a ton, am going to apply the knowledge right away, and I know it took you a lot of work to do this.

[@AndreasSpiess]

All videos take a lot of production time. So, it is nice to know that you like them...

[@CuddleStories]

Love your videos! Can't wait until I can begin using solar panels myself

[@AndreasSpiess]

Go for it!

[@sericonti]

Thanks for sharing I learned a lot from this and your videos. I am building a weather station using ESP8266 and this is spot for my power requirements. I live in Malta so solar irradiance should be similar to that of Dubai. Many thanks.

[@AndreasSpiess]

You are welcome. It should be easy to generate enough power where you live ;-)

[@Fifury161]

Wow! Thanks for sharing your efforts! I may have to make a solar charged battery pack now!

[@AndreasSpiess]

:-)

[@souzamce]

Thank you so much Andreas. You are doing an amazing job. Your videos are simply perfect.

[@AndreasSpiess]

Thank you for your nice words!

[@taokodr]

Wonderful video! I've saved it for future research purposes. Thank you for making it! :)

[@AndreasSpiess]

You are welcome!

[@vatterger]

That's an interesting project! One thing though, since these small solar powered devices will stay outside for some years ideally: Did you account for the degradation of the 18650 when fully charged in summer? The cell will degrade much faster then it has to if the temperatures are up and it's fully charged, even though it doesn't need the additional capacity in these conditions. You could even reduce the charge limit dynamically based on the mean temperature to get maximum lifespan. Thanks for your informative videos!

[@AndreasSpiess]

You mention another complication to the project. It will depend on the way I will implement MPPT. If I use a micro controller, I can control all these parameters. With normal MPPT controllers, this is not possible (I assume).

[@vatterger]

Andreas Spiess That makes sense, it wouldn't bring huge enough benefits for the time spent implementing it.

[@chuckwilcox6997]

Great detail, appreciate the info. Yes, I agree with other comments, a well organised video. Thanks again Andreas.

[@AndreasSpiess]

:-)

[@qkb3128]

Loved the recap!

[@AndreasSpiess]

Thank you!

[@steffen7398]

Hi Andreas, good information, thank you. I am running an arduino based weather station with solar power in Zurich. I made good experience with a charger module. This is the one: 03962a / TP4056. but there are two versions, one with dedicated battery connectors and one with shared ones. I prefer the newer version with dedicated connectors. Cheers SJ

[@AndreasSpiess]

I should have one of these and will try it out. Thanks for your feedback.

[@robertkes]

Love it, very useful. I'm working on IoT device that will send data only once per 20mins, then in sleep mode.

[@AndreasSpiess]

Thank you!

[@attilaturgut9287]

Thanks Andreas you saves my times and moneys . Very helpful and experimental video Great job.I hope God gives you a more healthy and long life.Best Regards

[@AndreasSpiess]

Thanks!

[@QWACHU]

I love Your videos. You are encountering and describing with easy words (and tests!) many of problems with building IoT devices. Not only simple "Hello World" projects. :)

[@AndreasSpiess]

Thanks! There are many others around for the "Hello world" stuff. And sometimes, I am also using these examples if I start something new...

[@QWACHU]

Yes, me too. But sometimes I wonder if all KZbin Tutorials stopped on the same "Hello World" examples and that is all you can get from IoT.

[@mrakjunior]

Certainly your channel deserves more subs.

[@AndreasSpiess]

Thank you!

[@maxgobel]

Great video, I'm working on a project for a solar powered sensor, and this was very helpful. Thank you very much!

[@AndreasSpiess]

You are welcome!

[@damny0utoobe]

I was just wondering about this....and my favorite Swiss vlogger comes through

[@AndreasSpiess]

Coincidence or luck? Or maybe both...

[@yengamatic]

Wow! Really good video, very nicely done. I can't wait to watch the next in the series, haha.

[@AndreasSpiess]

Will come!

[@ModestMaker]

These videos are wonderful treasures Andreas - Thank You!

[@AndreasSpiess]

You are welcome!

[@laszlolebrun4114]

Hi thanks for the video. Yes designing a 24/24/365 solar powered system is quite different than to design a device to maximize solar harvesting during sunny days. Once you design it to gather enough power to pass bad winter days, you will discover that the panels will deliver > 500 times too much energy during hot sunny days. So one thing to consider is what to do with that energy? My current approach is to use that energy to power fans, that will cool down the whole system.

[@AndreasSpiess]

The fans are a very good idea ! I hope, the factor will not be >500...

[@laszlolebrun4114]

Ups! Of course >500 was exaggerated. I meant factor ~50. I have tested my 5W panel to deliver 15-20mA on rainy days compared to 800mA maximum in bright sun. Anyhow these little 20mA are reducing the energy deficit by ~25%. I will activate the fans by the signal "fully charged" of my charger modules, essentially to avoid a source voltage increase above the specs of the regulator when it stops dragging current. Additionally the Arduino will be able to activate them temporarily as well, when its own temperature exceeds a threshold, that will improve the panel efficiency.

[@AndreasSpiess]

Sounds like a good idea! Thanks for the tip

[@GeorgePucci]

Always a great video, congratulations !!!

[@AndreasSpiess]

Thank you!

[@norm1124]

Viele Dank für die soliden Erläuterungen und ... gute Bierwahl!

[@AndreasSpiess]

Danke! Eigentlich hätte ich ein "Farnsburger Bier" nehmen sollen. Da bin ich nämlich sogar Aktionär...

[@WOnken]

Tollen Video, ich freue mich schon auf die Fortsetzungen....

[@AndreasSpiess]

:-)

[@YuriPetrovich]

Very very educational. Thanks for your knowledge, Andreas.

[@AndreasSpiess]

My pleasure!

[@Luke-san]

Interesting video and very nice explanation. For the next episode for the mppt, pwm, etc chargers please take into account that mppt chargers usually draw much more current than the other ones and that it might not be as good as a pwm one especially for low power situations.

[@AndreasSpiess]

+Luc Peeters This is very important! Do you have examples of boards or tests?

[@AndreasSpiess]

Most of these chargers are not for this scenario They use quite high voltages and are rated for many amperes. I did not find many of them suited for low power applications so far.

[@Luke-san]

So so true. Seems we need to make it ourselves or modify . I have a couple of these but with the display, which can be turned off.. www.ebay.co.uk/itm/1PCS-5A-MPPT-Solar-Panel-Controller-Voltage-Step-down-Module-Constant-Current-/292153107129 You need to make sure to use a Schottky diode (place for that on the PCB) and most of these mppt boards since when you have no solar the power from the batt goes back into the board. But this makes it a bit more difficult since the tolerance of all components might make the batt charge over 4.2 Volt. So if I would use these kind of things to make a L-Ion charger I would prefer 2 instead of 1 cells but to make it charge only to 4 Volts which is better for Li-Ion cells anyway. Already looking fwd to next Sunday.

[@cantinasongband]

I drank that beer when I was in Switzerland! It's really good!

[@AndreasSpiess]

Thank you!

[@MakerBen]

This man makes me happy, Keep making great videos! you inspire me :) I want to learn how to make cool things like this ^

[@AndreasSpiess]

I like that. Thank you!

[@steveroberts1861]

Wonderful solar video thanks Andreas

[@AndreasSpiess]

You are welcome

[@phinok.m.628]

Well, your calculations may have left enough margin for error there. But I feel like it's worth mentioning, that if your battery is large to get you through the night (not the winter), you should design things to work in the worst case scenario and not on average across the whole year. In the summer you will be getting more power than the average and in the winter less. Therefore if your solar panel produces enough power on average over the year, that doesn't mean it will produce enough power in the winter. Especially not on a unusually cloudy day after your solar panel has collected some dust etc. Personally I would oversize the solar panel just a little bit more to be safe.

[@AndreasSpiess]

I think the formulas are here and you can select whatever scenario fits for you. I just made examples.

[@jorgeguberte]

Very informative. Thank you very much. Cheers not from Basel but from Brasil, haha

[@AndreasSpiess]

And with lots of sun, I assume ;-)

[@jorgeguberte]

Andreas Spiess in the winter it's not as bad as in Europe, but some cities more to the north are much better than here (São Paulo). A cloudy day in those cities is very rare

[@WarthogARJ]

I'm just starting to look into this, so I don't have your hands-on experience, but I was thinking about how one can monitor solar intensity with respect to solar panels. A Lux meter is not too bad, because most panels use the 380-750nm range, but it's not a full correlation with Lumens. The cheaper Lumens meters use two photo-diodes, and calculate Lumens based on their outputs. But their output is not linear, although it does roughly correspond the the human eye. A solar panel has a much more linear response to wavelength, in the visible region. Maybe you could just use a standard solar panel of the same type as you use in your tests, and record the power generated from it during each test. Then that would automatically take into account the effects of atmospheric moisture, dust etc on solar radiation intensity. You could even use that to normalize your test data by using the standard power output for a given series of tests: just record it as you do each test. Then if something happens during a specific test you will both know it and be able to compensate for it.

[@AndreasSpiess]

I think, I will only try to monitor the energy which really came from the panel, because I am not interested in the phases with energy in ambundance, only for the critical phases. This is different to most applications where you want to get must out of your panels.

[@WarthogARJ]

That's not what I mean't. You tried to use a Lux reading to compare readings taken at various times for your system, and my point is that Lux is not an ideal measurement for solar power: the wavelengths and weightings over these wavelength ranges are different for Lux and solar radiation. I understand that you want to concentrate on the low energy times: Winter basically. So you need some way of making a quantitative measurement of how well a specific system behaves for a given amount of solar energy. So you need to be able to measure solar energy.

[@olivierbraun941]

your video shows all the dilemma of solar power to be used as a single source of power, and this is true the same way for off grid houses in remote areas, and even grid scale. the effort to cover the last 10 % of energy for the darkest cloudiest winter days is economical nonsense if you have to throw away your resulting overproduction in summer. So this may be economical for small loads and when it still comes cheaper than connecting a line or adding an alternative power source. The many parking ticket vending machines are a widespread application where this makes sense. When grid power is available i have doubts if using solar and batteries is so much more eco-friendly in a lifetime consideration.

[@AndreasSpiess]

I agree with you. My application was for small power off-grid where a cable is not an economical solution. For other panels connected to the grid, there are many other considerations

[@amyslivets]

Super structured video. Awesome. Thanks. Waiting for next episode)

[@AndreasSpiess]

:-)

[@keen2461]

Excellent video as usual. Thanks for your time.

[@AndreasSpiess]

You are welcome!

[@SianaGearz]

Optimal power point tracking may also be relevant to mechanical generators like wind generators and bicycle dynamo. That being said, is wind a viable way to support a wireless sensor? If it's not viable on its own, it may provide just the right supplementary power just for the bad weather days, if your climate happens to make rainy days also windy.

[@AndreasSpiess]

I think, wind is also viable, if available in quantity. In my region, we do not have stable winds, so, the effort would not outweigh the reward

[@georgekot6377]

Another very useful video (tutorial). Looking forward to the next.

[@AndreasSpiess]

:-)

[@ursodermatt8809]

this was an interesting calculation. however, in practise, larger solar panels are cheaper compared to the battery. in other words, calculate the solar panel size for the cloudy swiss short winter days. you might have 20 times more energy during a sonny summer day than the device uses. but who cares if the solar panel is large enough to run it in a cloudy winter day. also, batteries and panels degrade over time. the mppt controller will use small current during the night. as a fist of rule, the battery should only be large enough to tide you over the longest night. and the solar panel large enough to tide you over a cloudy winter's day. and then double both up. just to be on the safe side.

[@AndreasSpiess]

Interesting different strategy. You seem to be more experienced with solar panels than I and your thinking is logical. Thanks! Concerning charger: If I do my own, I plan to "deep-sleep the controller if no sun (= panel voltage) is available and also switch the charger completely off. Like that, I hope to achieve a current in the micro amperes rather than milli amperes. I do not know how much current a commercial controller will use in this conditions. BTW: How much power I can expect (per m2) on the worst day in Switzerland?

[@ursodermatt8809]

well. the worst day could be close to zero. the more cloud cover the less solar generation. i havn't lived in switzerland for 40 years, but remember 4 winter months with overcast, fog, high fog and hardly any sun. but i suppose probably 10% of the panel's peak value for a rough guess.( you might check the solar irradiation map or install a weather station with a w/m2 device installed. also, in cloudy weather a panel oriented directly into the sky will generate more energy then oriented into to covered sun. my experience is of running the house from solar year round. fortunately the winters here (sydney area. solares schlaraffenland) are relatively sunny compared to switzerland. we "overpower" the solar charger. that means often the charger limits the possible solar during summer at noon. but then in winter you really want that extra over powering.

[@diydsolar]

andreas you could also use this way ( I have check it): 1. protect your battery trhough a TL431 IC from lowvoltage (you could also take apart this part of the schema. Depends on battery price or a system that avobe minimum voltage your system (arduino o esp8266) advises you about the low voltage problem. Depends on if the circuit is near you or not). 2. to protect your battery for overvoltage, the best way is a little MOSFET and a pin from arduino, when you see that your battery's voltage is bigger than a predefined value, you can shortcircuit your panel. It is a very low value charger controller, and I know that you lost power as the pane voltage will be always the battery voltage, but it is the simplest way. If you need and example I could send you my schema. Regards,

[@kiran-hh4tq]

Sir your explanation is awesome...!! Thankyou..and we need more videos from you.

[@AndreasSpiess]

Every week one (and sometimes a "bonus" one.)..

[@kiran-hh4tq]

Andreas Spiess sir we need gsm, sensors (proximity) video. Where GSM sends msg only twice a day but sensor senses actively.

[@svenpfister5642]

A Review of a full setup would be nice. E.g. OpenHAB2, MQTT, ESP32, Mongoose OS, powermanagement as well as solar and lipo setup. This would be interresting for building wireless sensor devices and integrate them into a free home automation system.

[@AndreasSpiess]

I think, the systems setup would be your job ;-). I concentrate on the parts. Like that, my content is more widely useful.

[@svenpfister5642]

Nice videos by te way 😉

[@AndreasSpiess]

:-)

[@markifi]

you explained that quite clearly

[@AndreasSpiess]

Thank you!

[@eddyfontaineyoutu100]

Thank you Andreas, VERY informative ! I am waiting for the solar controller ! 🙂

[@AndreasSpiess]

Me too. But there is some learning ans working between the wish and reality...

[@eddyfontaineyoutu100]

Take your time ! 🙂

[@eloistreeraw]

Thanks. Great works. (I will come back to this video when I will be ready to study this field).

[@AndreasSpiess]

You are welcome!