Thanks for your videos. In regards to having the solar panel voltage being “LOWER” than the battery voltage. It depends on the MPPT. I’ve never used a boost mode MPPT before. But, I’ve ran a small DIY solar system kit for years with solar panels wired in series at higher voltages to charge a 12v battery bank. In addition, both my Ecoflow and my Bluetti are able to do the same thing, taking higher voltages up from 150v and stepping it down to charge a 48v internal battery bank. Most sogens and MPPT out there can step up or down the voltages. I feel it’s better to have your solar panels closer to the battery voltage, then there is less work for the MPPT. In some cases, a pwm charge controller might be better suited for the job.
Both boost and buck mode MPPT's can be equally efficient. In large installations like this we'd agree that usually series connected panels and buck converters makes most sense. But then we'd loose the flexibility and redundancy of being able to run just a couple panels at a time, since even 2 panels in series won't get us above the 72V pack.
If you put series panels in partial shade, the current through all of the cells decreases. If you put parallel panels in partial shade, the lit ones will short out through the shaded cell. Iff the ratio is high enough, you can burn up that shaded cell. You can make a mppt that accepts parallel panels and prevents this, but You really want to be careful with more than 2 or 3 just shorted in parallel. Also, ideally you should have a high enough voltage to use a buck mppt for minimum current, but you guys are probably rightfully afraid of the voltage.
Two things. 1), Thanks Justin. That was very helpful. I am slowly starting to get a grip on solar. (slowly, very slowly) 2), Where did you get your Tee shirt. Love it!
1) Glad to hear that, more technically nuanced videos will follow but we wanted to start easy! 2) From a very special trip to Russia and Kazakhstan to see a Soyuz rocket launch! ( instagram.com/p/BrNFSA-gLd4/ )
Yeah our deck is so low compared to the neighboring floathomes that all the geographic clues are blocked from the skyline, so I see it's hard to tell! Not Ladner or Granville Island though.
Thanks for the information Justin, curious if you have a MPPT on each panel do you have to worry about the MPPT’s fighting with each other when you get into the voltage control charge region?
As TSBG wrote, no problems at all. It's just like parallel connecting regular chargers which is also just fine. But you will have a state at the end of charging when some of the MPPT's think that the pack is fully charged, while others will still be putting in current, since they all have some variation in their voltage calibrations.
@@GrinTechnologies ‘Smells baaad’. 6 hours !!!! 🔴🦌. 5 days or more sitting inside your stomach puuuu-trifying !!! No fibre if you eat animals in their secretions !!! Timelapse. ua-cam.com/video/lmSrUvgWiqE/v-deo.html .... 🤢🤮.. That’s why I am vegan !!!! Your teeth are flat 😬. And your stomach is very very long, “combined length of the small and large intestines is at least 15 ft in length”. We are herbivores. The ape family. ✅❤️😬💪🦍 GorilIas never ever eat animals, they are huge !!! 98.6% the same as us !!! And I’ve gotten bigger and stronger and fitter on a plant based diet. Scientific fact !!!! Fat deposits clog the arteries, eating animals and their secretions. Deodorant mask the symptoms but the shoes and socks and armpits.. 🍳🍖🍔...🦠🧟♂️👕🧦🥾🤮
@@GrinTechnologies Heart attack pictures, fatty foods is animaIs cIogged arteries, hard arteries, PH 5, no fibre🧟♂️🦠🍔🥓🥩🍗🍳🧀... 🤮. Vegans don’t stink. PH 7 , plants have fibre ✅😉, vegans are peaceful, Peer review science. Actual pictures of the heart. ua-cam.com/video/15wgYsToORM/v-deo.html !!! ua-cam.com/video/pFPFnhfuLrE/v-deo.html Vegans don’t have this problem because that is the animals. Vegans don’t get clogged arteries, 4% cancer if you’re vegan. Meat based diet 51% death rate. That is extremely high for a frigging burger etc. Gorillas in the wild, have 1 percent cancer. And they never ever eat animals !!! Peer review science !!!! UA-cam delicious vegan food. Time to change ✅❤️😉
Do you have diodes in the paralleling adapter? In the case of one panel shaded, the unshaded one can backfeed power into the shaded one. Without diodes you'll see less power output.
I believe that the junction in the panel wiring has a diode, but it turns out that the Sunpower solar cells have such a low reverse-bias voltage drop (~2.5V / cell) that the partially shaded array still always maintained a positive voltage and contribution to output power. So a diode at the panel level wouldn't have come into play in this example. But if the entire panel was shaded then it would be a bit different. May test that in a follow-up Vid.
Tradisjonelle most panel has a blocking diode, but in later years panels intended for large scale solar do not have blocking diode. I would assume the sizes you use on a bike would have blocking diodes. Anyway you can buy blocking diode with MC4 connector.
You did not have enough shading to show a difference. The panels themselves may have some parallel wiring which limits the effect of shading in certain cases.
It's mostly that the Sunpower solar cells have a very low breakdown voltage drop, so a few shaded cells do not cause nearly the same degree of plummeting voltage as you have with other brands of solar cell.
Would you put Diode between 2 mppt boost pluged in parallel ? I'm quite afraid that if a pannel gets shaded, the voltage output shall drop for a quick moment, therfore the energy would go from the pannel to the other mppt more than the battery ? isnt that dangerous ? Thanks anyone for an answer. ;-)
I guess i've got my answer, from a bit of logic ?... I suppose even cheap Mppt already have a diod before the output, because in the contrary when plug to the battery with no sun, the mppt would instantly burn ....
There is no need to put a diode the parallel connected outputs of the MPPT's. Each one will boost whatever panel is hooked up to it up to the battery voltage at the maximum power point for that panel. If one of the panels is shaded, it's MPPT will simply be contributing less amperage to the battery than the other MPPT's with unshaded panels. Having panels parallel connected on the input side of the MPPT is a totally different story, but there are no parallel connected panels in this setup.
@GrinTechnologies as always, your response is so valuable, clear and simple. Thank you so much for your time !!!! About to send to the team pictures of my solar trike soon ! Good day to you all
I believe he said the panel voltage was around 30V. That would be 120v for 4 in series which is far more than the input voltage of the controller. He's using controllers that boost the voltage of the panels, for that you would need a controller that steps down the voltage. Which is more standard, and usually more efficient so might be a good way to go. Although shading on just one panel would knock out most of the whole set.
@@BenBrand i saw 19v on the example sorry. Why don't you put all of the panels in series and bring it up to 240 volts for 8 panels then step down. Wouldn't that be the most efficient way
@@quevicular stepping down is more efficient yes, but since he normally uses controllers for e-bikes, they are usually boost only because of the low panel count and high vintage of the battery. He would probably be better with higher voltage and step down controllers which are more common for these larger systems. But only for groups that would not be shaded, as if you had all the panels in series and one was shaded by the mast say, it would knock out the whole string.
It's a good question, but 4 main reasons: 1) We already have a good stock of these boost mode MPPT's 2) All series is OK when all the panels are at the same angle to the sun, but when some are at different angles than others, then the output of a series connection will be quite a bit worse. Groups of panels will just end up being bypassed from the pass diode rather than contributing to the output if they can't supply as much current as the better angled panels. 3) I'm comfortable going to up 72V on the boat, but having a 200+ volts routed above deck would make me a little uneasy. 4) I also like the redundancy of having multiple charge controllers running instead of banking on just one. It's for similar reasons that we've got a dozen independent 72V batteries hooked up in parallel, rather than one very large high capacity battery with one large BMS circuit. There's some comfort in knowing that one electronic parts failure won't take the system out.
Somehow I was able to follow along and understand the concepts. Clear explanation with great delivery.
Thanks for your videos. In regards to having the solar panel voltage being “LOWER” than the battery voltage. It depends on the MPPT. I’ve never used a boost mode MPPT before. But, I’ve ran a small DIY solar system kit for years with solar panels wired in series at higher voltages to charge a 12v battery bank. In addition, both my Ecoflow and my Bluetti are able to do the same thing, taking higher voltages up from 150v and stepping it down to charge a 48v internal battery bank. Most sogens and MPPT out there can step up or down the voltages. I feel it’s better to have your solar panels closer to the battery voltage, then there is less work for the MPPT. In some cases, a pwm charge controller might be better suited for the job.
Both boost and buck mode MPPT's can be equally efficient. In large installations like this we'd agree that usually series connected panels and buck converters makes most sense. But then we'd loose the flexibility and redundancy of being able to run just a couple panels at a time, since even 2 panels in series won't get us above the 72V pack.
If you put series panels in partial shade, the current through all of the cells decreases. If you put parallel panels in partial shade, the lit ones will short out through the shaded cell. Iff the ratio is high enough, you can burn up that shaded cell. You can make a mppt that accepts parallel panels and prevents this, but You really want to be careful with more than 2 or 3 just shorted in parallel. Also, ideally you should have a high enough voltage to use a buck mppt for minimum current, but you guys are probably rightfully afraid of the voltage.
Cool shirt! I'll have to google now where that bar is =)
Two things.
1), Thanks Justin. That was very helpful. I am slowly starting to get a grip on solar. (slowly, very slowly)
2), Where did you get your Tee shirt. Love it!
1) Glad to hear that, more technically nuanced videos will follow but we wanted to start easy!
2) From a very special trip to Russia and Kazakhstan to see a Soyuz rocket launch! ( instagram.com/p/BrNFSA-gLd4/ )
Great summary, thanks a lot Justin!
Good info, clearly presented, thanks! At first I thought Granville Island, but now thinking Ladner?
Yeah our deck is so low compared to the neighboring floathomes that all the geographic clues are blocked from the skyline, so I see it's hard to tell! Not Ladner or Granville Island though.
I've got 2 100 watt panels on a trailer
Thanks for the information Justin, curious if you have a MPPT on each panel do you have to worry about the MPPT’s fighting with each other when you get into the voltage control charge region?
As TSBG wrote, no problems at all. It's just like parallel connecting regular chargers which is also just fine. But you will have a state at the end of charging when some of the MPPT's think that the pack is fully charged, while others will still be putting in current, since they all have some variation in their voltage calibrations.
@@GrinTechnologies ‘Smells baaad’. 6 hours !!!! 🔴🦌. 5 days or more sitting inside your stomach puuuu-trifying !!! No fibre if you eat animals in their secretions !!! Timelapse. ua-cam.com/video/lmSrUvgWiqE/v-deo.html .... 🤢🤮.. That’s why I am vegan !!!! Your teeth are flat 😬. And your stomach is very very long, “combined length of the small and large intestines is at least 15 ft in length”. We are herbivores. The ape family. ✅❤️😬💪🦍 GorilIas never ever eat animals, they are huge !!! 98.6% the same as us !!! And I’ve gotten bigger and stronger and fitter on a plant based diet. Scientific fact !!!! Fat deposits clog the arteries, eating animals and their secretions. Deodorant mask the symptoms but the shoes and socks and armpits.. 🍳🍖🍔...🦠🧟♂️👕🧦🥾🤮
@@GrinTechnologies Heart attack pictures, fatty foods is animaIs cIogged arteries, hard arteries, PH 5, no fibre🧟♂️🦠🍔🥓🥩🍗🍳🧀... 🤮. Vegans don’t stink. PH 7 , plants have fibre ✅😉, vegans are peaceful, Peer review science. Actual pictures of the heart. ua-cam.com/video/15wgYsToORM/v-deo.html !!! ua-cam.com/video/pFPFnhfuLrE/v-deo.html Vegans don’t have this problem because that is the animals. Vegans don’t get clogged arteries, 4% cancer if you’re vegan. Meat based diet 51% death rate. That is extremely high for a frigging burger etc. Gorillas in the wild, have 1 percent cancer. And they never ever eat animals !!! Peer review science !!!!
UA-cam delicious vegan food. Time to change ✅❤️😉
Do you have diodes in the paralleling adapter? In the case of one panel shaded, the unshaded one can backfeed power into the shaded one. Without diodes you'll see less power output.
I believe that the junction in the panel wiring has a diode, but it turns out that the Sunpower solar cells have such a low reverse-bias voltage drop (~2.5V / cell) that the partially shaded array still always maintained a positive voltage and contribution to output power. So a diode at the panel level wouldn't have come into play in this example. But if the entire panel was shaded then it would be a bit different. May test that in a follow-up Vid.
Tradisjonelle most panel has a blocking diode, but in later years panels intended for large scale solar do not have blocking diode.
I would assume the sizes you use on a bike would have blocking diodes.
Anyway you can buy blocking diode with MC4 connector.
You did not have enough shading to show a difference. The panels themselves may have some parallel wiring which limits the effect of shading in certain cases.
It's mostly that the Sunpower solar cells have a very low breakdown voltage drop, so a few shaded cells do not cause nearly the same degree of plummeting voltage as you have with other brands of solar cell.
Someone please make a kit to buy for us solar energy challenged.
which MPPT solar charge controller did you use?
Ah, that was with this model here:
ebikes.ca/shop/electric-bicycle-parts/solar/adjustable-400w-boost-mppt.html
Would you put Diode between 2 mppt boost pluged in parallel ?
I'm quite afraid that if a pannel gets shaded, the voltage output shall drop for a quick moment, therfore the energy would go from the pannel to the other mppt more than the battery ? isnt that dangerous ?
Thanks anyone for an answer. ;-)
I guess i've got my answer, from a bit of logic ?...
I suppose even cheap Mppt already have a diod before the output, because in the contrary when plug to the battery with no sun, the mppt would instantly burn ....
There is no need to put a diode the parallel connected outputs of the MPPT's. Each one will boost whatever panel is hooked up to it up to the battery voltage at the maximum power point for that panel. If one of the panels is shaded, it's MPPT will simply be contributing less amperage to the battery than the other MPPT's with unshaded panels.
Having panels parallel connected on the input side of the MPPT is a totally different story, but there are no parallel connected panels in this setup.
@GrinTechnologies as always, your response is so valuable, clear and simple. Thank you so much for your time !!!! About to send to the team pictures of my solar trike soon !
Good day to you all
varshana?! please reply...
If you've got a 72 volt battery pack then why don't you hook up for panels in series and then use only one mppt
I believe he said the panel voltage was around 30V. That would be 120v for 4 in series which is far more than the input voltage of the controller. He's using controllers that boost the voltage of the panels, for that you would need a controller that steps down the voltage. Which is more standard, and usually more efficient so might be a good way to go. Although shading on just one panel would knock out most of the whole set.
@@BenBrand i saw 19v on the example sorry. Why don't you put all of the panels in series and bring it up to 240 volts for 8 panels then step down. Wouldn't that be the most efficient way
@@quevicular stepping down is more efficient yes, but since he normally uses controllers for e-bikes, they are usually boost only because of the low panel count and high vintage of the battery. He would probably be better with higher voltage and step down controllers which are more common for these larger systems. But only for groups that would not be shaded, as if you had all the panels in series and one was shaded by the mast say, it would knock out the whole string.
@@BenBrand true enough
It's a good question, but 4 main reasons:
1) We already have a good stock of these boost mode MPPT's
2) All series is OK when all the panels are at the same angle to the sun, but when some are at different angles than others, then the output of a series connection will be quite a bit worse. Groups of panels will just end up being bypassed from the pass diode rather than contributing to the output if they can't supply as much current as the better angled panels.
3) I'm comfortable going to up 72V on the boat, but having a 200+ volts routed above deck would make me a little uneasy.
4) I also like the redundancy of having multiple charge controllers running instead of banking on just one. It's for similar reasons that we've got a dozen independent 72V batteries hooked up in parallel, rather than one very large high capacity battery with one large BMS circuit. There's some comfort in knowing that one electronic parts failure won't take the system out.