MPPT vs PWM: Fast comparison for off-grid solar

[@WillProwse]

~~~~~~~~~~~~~~~~~~~~~~~~~~~ Does off-grid solar confuse you? Check out my DIY friendly website for solar system packages and product recommendations, and so much more! www.mobile-solarpower.com Join our DIY solar community! #1 largest solar forum on the internet for beginners and professionals alike: www.diysolarforum.com Check out my best-selling, beginner-friendly 12V off-grid solar book (affiliate link): amzn.to/2Aj4dX4 If DIY is not for you, but you love solar and need an offgrid system, check out Tesla Solar. Low prices and great warranty, and they can take your entire house offgrid with their new Powerwalls: ts.la/william57509 ~~~~~~~~~~~~~~~~~~~~~~~~~ My solar equipment recommendations (Constantly updated! Check here first): 12V/48V Lithium Batteries: www.mobile-solarpower.com/solar-batteries.html Solar System Component Directory: www.mobile-solarpower.com/solarcomponents.html Plug-N-Play Systems: www.mobile-solarpower.com/full-size-systems.html Complete 48V System Kits: www.mobile-solarpower.com/complete-48v-solar-kits.html DIY Friendly Air Conditioner/ Heat Pumps: www.mobile-solarpower.com/solar-friendly-air-conditioners.html Complete 48V System Blueprint: www.mobile-solarpower.com/48v-complete-system-blueprint.html ~~~~~~~~~~~~~~~~~~~~~~~~~~ My Favorite Online Stores for DIY Solar and Coupon Codes: -Current Connected: SOK, Victron and High Quality Components. Best prices and warranty around: currentconnected.com/?ref=wp -Signature Solar: Cheap Server Rack Batteries and Large Solar Panels: www.signaturesolar.com/?ref=h-cvbzfahsek -Ecoflow Delta Official Site: My favorite plug-n-play solar generator: us.ecoflow.com/?aff=7 -AmpereTime: Cheapest 12V batteries around: amperetime.com/products/ampere-time-12v-100ah-lithium-lifepo4-battery?ref=h-cvbzfahsek -Rich Solar: Mega site and cheaper prices than renogy! Check them out: richsolar.com/?ref=h-cvbzfahsek -Shop Solar Kits: Huge site with every solar kit you can imagine! Check it out: shopsolarkits.com/?ref=will-p -Battery Hookup: Cheap cell deals bit.ly/2mIxSqt 10% off code: diysolar -Watts 24/7: Best deals on all-in-one solar power systems, with customer support and distribution here in the USA: watts247.com/?wpam_id=3 ~~~~~~~~~~~~~~~~~~~~~~~~~~~ Contact Information: I am NOT available for personal solar system consult! If you wish to contact me, this is my direct email: [e-mail] Join the forum at diysolarforum.com/ if you wish to hang out with myself and others and talk about solar FTC Disclosure Statement and Disclaimers: Every video includes some form of paid promotion or sponsorship. Some links on this youtube channel may be affiliate links. We may get paid if you buy something or take an action after clicking one of these. My videos are for educational purposes only. Information is subject to change/update at any time. Electricity is DANGEROUS and can kill. Be smart and use common sense :) DIY Solar Power with Will Prowse is a participant in the Amazon Services LLC Associates Program, An affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com

[@our12silly]

Dude. This video rocks and it's 4 years old. Thank you.

[@davelinaker1531]

You’re sharing knowledge from a user with experience. Sizing the items in the setup is not easy to do without experience.

[@doloresmccartney3186]

WOW, you are so great and have taught me so much... I knew nothing...I’m just an old 68 year old woman👵🏼 trying to learn. Still trying... love you.

[@nohphd]

Will, thanks for this succinct but valuable video. I’m living in the ever so cloudy, ever so northern PNW. I’m part of a group building an amateur radio emergency network on remote, isolated small towers. The solar/battery system is about 50% of the kit cost and increasing the efficiency is paramount. There are a lot of KZbin videos on solar but I keep coming back to your channel for clear answers and actionable suggestions. Thanks again!

[@philc.9280]

Many of us are totally satisfied with using PWM controllers. I am not a power hog in my RV and my 400 watts of solar panels, PNW controller and two deep cycle batteries are more than enough to handle the refrigerator, TV, laptops and lights. I think I only paid $14 for that controller on eBay.

[@vidaliasoleil2714]

Your presentation gave me confidence that a $13 PWM on our small sailboat, running as back up for essential systems like nav lights, depth sounder and to back up GPS and chartplotter was fine. No need to spend over $120 on a solar system! Sail primarily in summer on warm sunny days, stays cool in bottom of lazarette where charge controller, batteries located, less than three feet of wire to connect. 12 volt 35 amp AGM battery x 2, plus starter battery. 100 watt solar panel. Worked great past two years.

[@procrastinator1842]

I moved from the cheap blue PWM to a $30 Powmr/Bateria Power miniature mppt and the power harvesting difference is astounding. I'm talking twice as much at earlier and later sun hours.

[@mosaabkhalifa6248]

The best video that explains what MPPT and PWM is designed for. Thanks Will! Sending best wishes from Libya!

[@heathbarnett3451]

Thanks for clarifying Will! I found myself comparing the two while watching your last video.

[@brianstewart3027]

I came here seeking knowledge and you do an amazing job at transferring knowledge.. Man, I really appreciate your videos.

[@anarex0929]

The man has integrity too. Owns his mistakes and doesn't drag it out. Hard to come by.

[@GensetExpert]

@@anarex0929 1

[@dtvking]

Couldn't agree with you more Will. I just changed from PWM to MPPT and over the last week, I am getting 2 to 3hrs more life from the batteries in part cloudy/part sunny days here in North London and I'm seeing a 4 to 5amp output from my panels in just normal daylight (no sun) when I was getting nothing on PWM without sun. Well worth the upgrade.

[@collegesynewave]

thanks for that :)

[@Ziplock9000]

What CC are you using mate?

[@dtvking]

@@Ziplock9000 Renogy Rover 40 amp

[@Ziplock9000]

@@dtvking Thanks mate

[@askaraskar155]

Sir, how do you monitor your system, with what specific devices?

[@AJOTECH21]

You know about that. For me I learned from you about the solar system. I made my own solar powered. And I made my own battery power box. Thank you for your advice, support and suggestions.

[@craigwallace4202]

Thank you for every single one of your videos, Will. Your efforts are appreciated more than you know.

[@francespueo5367]

Thank you. I'm learning safety, and how to choose what is important and what is not.

[@CorpsMedia]

Hey man, I don't know your background but you make some incredible videos. I'm an electrical engineer of 10 years and I'm just starting to get into KZbin showing people about electrical installs in vehicles. Any time I have to cover a topic on solar I will be refering my viewers to your videos 👍💪

[@wayneleary4204]

Cheers for the vid,,, made my mind up MPPT..CLEAR AND UNCONFUSING, Living in the UK i need an MPPT.. WELL DONE LAD

[@woodlanditguy2951]

This was super informative! I just started out with Solar and building a small, 2 panel 400w (peak) system with two 12v 100Ah LiPo batteries. I got the batteries and panels first but have no idea what controllers to get. I got about 30 feet of wire from my panels to where I'm installing the controller. I think I will go with the MPPT due to the fact that I won't always have direct sunlight and may have cloudy weather from time to time. I will likely get a 2000W inverter. The inverter and battery will be right next to each other and indoors out of the elements. The MPPT will be outdoors but protected from rain.

[@MertTheDragonReborn]

This video helped me a lot. I had an assignment about the differences between MPPT and PWM charge controllers for a Lab-Course. This Video saved me so much time and clarified the most important parts in a short span of time. Greetings from germany!

[@Engineerboy100]

Plan to build an off-grid solar system soon. In the mean time I'm going to be watching a lot of your videos, Great content! Thank you!

[@peterhutchings6356]

Awesome video will. Happy to go down MPPT route now. Big shout out to Oregon or London people :) UK resident here 🤟🏻

[@MrWackozacko]

I honestly would never waste my time with anything other than the best Victron MPPT anymore, have gone through a bunch of PWM chinese ebay specials over the last decade. But my victron 48v20A has had 300kwh put through it over the last couple years and is still going strong

[@simon-k7m]

Living in the UK I got my answer straight away, cheers 👍

[@Yaman-D-Chhaya]

Very crisp Will no nonsence straight to the point men great Video, love and warm regards from India

[@Yaman-D-Chhaya]

Will I am a media post-production artist, worked at radio station as a sound and broadcast engineer, with little knowhow of Electronics, I started now in renewable energy and battery packs just now I have ordered 32650 LFP'S 3.2V 6Ah cells Would be making EV batteries first then shifting to 18650 LCO for any application Battery. I wish to make my own Inverter Will to make a consolidated unit with battery pack N DC ports, one can carry it anywhere please guide weather I should go in for the pure sine wave PWM or the routine Square wave design? My plan is to have all in one box battery Inverter DC ports 👍👍🌹🌹

[@mylifein75sqft87]

I suggest that you use a Bogart engineering SC2030 with it's tri metric meter TM2030 if you are going to do a PWM comparison. This system along with the use of a shunt would be a much better comparison. I have (3) 150 Watt panels connected in series on the roof of my van. I run these wires into a combined box inside my van. Each panel I on a 15 Amp breaker. Way safe. There many ways to skin a cat safely. I've been all over the US and my system works very well. When my Vmax Tanks batteries die, I'll go to a completely different system, probably L-ion batteries, 24V and maybe an MPPT charger. Thanks for your videos.

[@rvfeel-n-free6562]

I wish Will would do this comparison also. The Bogart Engineering Sc2030 pwm charge controllers mated with the tm2030 is a very good setup.

[@JohninTucson]

Excellent comparo you did on the different controllers ! I am on a YT LIVE at the moment (I'm Moderator and a poor man's Ed McMahon LOL). I need to talk to you at some point if you have the time Will - Things inside and outside of Solar/Lithium. Thank you either way buddy, your video content and quality is becoming top notch - WELL DONE.

[@heatherrenton2086]

Hmmm... I am think I might need to upgrade to an MPPT Solar Charge Controller. Thank you so much for the info.

[@westmountainadventures3606]

Thanks for bringing it back for beginners like me. I watch your videos because you talk beyond my knowledge base, but it’s nice to hear the basics from time to time so I can integrate it with the stuff I didn’t fully understand. D.

[@WillProwse]

Sure thing :)

[@martinc9867]

Highly recommendable information shared here,i am electrician,not working on the job for some years,and the solar industry has improved a LOT in the past few years,which makes it overwhelming even for people like me to get the big picture whats best right now.Thanks for sharing. Field experience is crucial,and its great to have a channel like this with the pros and cons of all products involved to make it run optimal.

[@vhfgamer]

I will add one thing that you haven't mentioned which is very important to many people. PWM is easier to make RF quiet than MPPT. So if you're running a radio operation off of your solar system, you will probably be using PWM.

[@mosesndege779]

That's a clear and precise comparison.Keep it up.

[@mokattravels4824]

I have no electronic background and want to do RV solar. You explain it so well. Great job. Thank you

[@sbollmeyer]

Thanks for the clarification, Will. Also, on selected models with the Triron EPever CC, they allow up to 150 volts. Crank up the volts on those string arrays if needed.

[@gwynneclark6372]

Success ,I have followed your book and videos and I have built my own solar generator ,thank for your help

[@kvjqxzz5905]

it is so nice to hear an expert, and with such infectious enthusiasm

[@davebagley6499]

Excellent primer! I use a 100 watt poly panel with 30 amp PWM (same price as 10 amp, so why not?) for the 2-12 volt batteries on my RV. And as you describe, it meets my needs in the southwest USA. Thanks.

[@sony5244]

I recently bought an 40 amps MPPT charge controller which is Made in India and its working great for the past 14 months

[@geraldwatkins3543]

I'm still trying to figure all of this out. I'm glad you mentioned the size wire for length of the Run. That had me very confused I'm trying to make a solar system that will run a live bands outside. I'm a sound man who refuses to do gigs inside clubs right now. Your videos are definitely helping me to brainstorm a system.

[@aaronjohnson2958]

Always a huge help when trying to plan a solar system, thanks Will!

[@ericsvalland4417]

PWMs have matured a bit since this video came out. The PWM installed in our 2024 RV has a max 600 watts. I'm sure MPPT's have matured also, so always best to check ratings/specifications of newer (and older) hardware.

[@lindabarnes1585]

Thank you for making the comparison so easy to understand and for providing links for purchasing.

[@Anthracite31]

Another excellent video Will. Thank you. Also, great job on your book. I’m in the process of putting together your 24v system on my cube truck.

[@upnorthcabinconstructs5441]

Great job-crystal clear and appreciate the note on wire size, which can be a HUGE expense!

[@carlthor91]

Those of us on sailboats also should go with MPPT controllers because at some point there WILL be shading of part of the array, by the mast/boom or radar antennae or wind generator, mounted close to the array (lack of real estate on the boat). This will be partly mitigated by the MPPT controller, bonus power, that would normally be lost by a PWM controller. Cheers all

[@Beansswtf]

5:54 Literally only reason why I came here. If you want to actually know the real differences then just skip this video.

[@PeterLawton]

I agree, Will. My design for the main home power includes MPPT. But on my remote land (entirely off-grid), there are a couple places far from the house where I want a little electricity for a sensor, and don't want to change out batteries periodically. I have in mind one panel, but even that is overkill, so PWM will suffice. That's my exception to the rule.

[@Samlol23_drrich]

Im doing a tiny setup to trickle charge a couple of car batteries for my generators. I could easily run it from electric. I've got to tell you that you've got Incredible knowledge in the field and I appreciate all these videos they're very interesting.

[@terrygilligan790]

Your making me smarter watching your channel 😄 off to buy an MPPT today. Really great video Thanks for that.

[@drymoonproperties]

I have asked myself this very question for a few days now. Thanks you helped me understand a little better.

[@leehudson1384]

Another thing worth mentioning (and something that's preventing me from getting an MPPT) is the difference in voltage between the solar array and the battery, for MPPT you need the solar array to be a much higher voltage than the battery to get the most out of it from what I understand. Wiring panels in series to accomplish this (which is what I could do) would mean shade has more of an effect.

[@AlexSwan]

I’ve been testing a cheap PWM vs a Redarc MPPT on a 120W solar blanket and the PWM is giving me almost 25% more power output. I’m guessing this is why?

[@reinhard8053]

@@AlexSwan That must be a quite strange combination of parameters. Generally the panel works best at about 18-20V for a "12V" Panel. A MPPT could use this voltage and convert it to the battery voltage with a higher current (same power). The PWM can only deliver the current from the panel which will be more or less the same as with a MPPT input but only with the battery voltage of about 14V. So you loose 4-6V on the panel side. The MPPT would need to be very bad at efficiency not to get a better result with the otherwise same setup.

[@richardthompson6802]

Actually, MPPT works even if solar panels are producing less than battery voltage. PWM requires solar voltage to be higher than batteries, and can't charge with more current than is available from the panels. MPPT can convert solar panel output to a higher or lower voltage and higher or lower current to get the best charging results from whatever its input is. It is probably true that the MPPT is more efficient at higher input voltages than it is from lower voltages, but it should still be at least as good as PWM in all circumstances, and often better.

[@reinhard8053]

@@richardthompson6802 Most MPPT chargers stop working, if the panel voltage is below the battery voltage. Not mainly because of the battery but because of the panels. And it also wouldn't accomplish anything with the usual panels. A "12V" panel will bring 18V if at least a little light is available. But it can't source any useable current, as the voltage breaks down if the panel is loaded and no power for charging is available. So you would need to have panels with a much lower nominal voltage at good light which on the other hand wouldn't work with most chargers and don't make any sense.

[@marchalthomas6591]

Concerning the tropics there are also great advantages to use mppt. In the rainy season it's cloudy half of the time. And we have a maximum of 12h/day of light.

[@BobgalaEugene]

Great knowledge comparing the two categories of charge controllers, thanks much. Please share the website

[@austinbobmanuel4065]

Agree completely. My offgrid PWM Installation is on fire here in Nigeria and it costs virtually peanuts

[@bryanbeast8662]

Thanks for this info. I'm watching the whole play list.

[@bennybaubles]

Other people say it’s not worth getting an mppt for a basic camping setup. I’m running a 100ah lipo with a 200w itechworld solar panel and it works a treat with the supplied pwm. By afternoon my battery was back at 100%. I think this scenario was left out of the video.

[@davidmartin3255]

Thank you Will. Very nicely done and appreciated. I wish you had put a link in the description for that mppt controller that you were holding at the very end.

[@Rob-cm9jr]

I have a 30amp pwm and (4) 100 watt panels and (2) 120ah deep cycle 12v batteries and a 400/800 watt inverter. I am going to hook it up on Friday. I think it'll work on my RV.

[@BubbaWarbucks]

I'm glad you pointed out the solar wattage ratings on those MPPT controllers. I have 640 watts of solar I'm going to put on the roof of my RV, and was going to install a 40A MPPT, but I hadn't looked at the solar wattage ratings at 12V. Most of them will not handle that much solar. So it's going to be a 45 or 50 amp charge controller for me. Thank you for all you're doing here.

[@stevevelobahn1814]

You could run any non-mppt hooked up panels to a dc-dc device and run fans and lights and maybe a daylight only fridge? I'm planning to have panels run a thermo-peltier fridge and a USB fan and light system.

[@BubbaWarbucks]

@@stevevelobahn1814 Sure but most people are going to run an inverter with their 120VAC appliances. Only tech nerds would think of doing what you're doing, and then when the sun goes down, you don't have power. The name of the game is storage.

[@epfd217]

Do some shopping. Often, two smaller solar controllers are better than one large one. You could probably get two 30 or 40a controllers for less than a 60a controller.

[@BubbaWarbucks]

@@epfd217 I only have one pair of wires from the roof to my solar compartment. Can I split that to go to two charge controllers?

[@stevevelobahn1814]

@@BubbaWarbucks wow! That's a great question! I sure hope there's a good.answer.

[@marcusaetius9309]

A good subject matter but you left out some key factors. With MPPT conversion efficiency drops the higher the array voltage relative to the battery bank voltage so I’m not convinced that on cloudy days an MPPT controller would deliver more amp hours than a PWM (it would be interesting to do a side by side test for this).

[@dienekes4364]

I'm finally dipping my toe into solar. I have a 12v battery with a cheap PWM controller, 400w inverter, and plan on buying a 100w solar panel from Harbor Freight to round out the system. This is for my garden shed, where the only things I need are lights (planning on using 12v so I'm not pulling power through the inverter) and power to charge my tool batteries. I _may_ run some 120v hand tools off of it as well, but only during the day and only when it's sunny out. I've had solar put on 2 different houses and really kick myself for the second one because the cost is so outrageous. With the house I'm in, I plan on putting the whole system together myself, so the garden shed is kind of a test run for the real thing. It's just a matter of getting the money together to build the system.

[@dragan3290]

In all honesty! I think a PWM doesn't compare to a MPPT charge controller! I did add 2 extra panels but it shared the load on PWM. I have 4 @240 watt panels. Australia has a fair bit of sun. MPPT is the only way! Top job. Cheers from Australia 🙂👍👍👍. Excellent vids.

[@jefersonnl]

Hey! Props for the video! Here is my setup, I live in a subtropical zone of Brazil(not tropical but still pretty sunny), I have three 150w (18.7v by 8.20A, all in parallel) solar panels, three 60A/12v car batteries(parallel) and a 12v to 120v inverter. I am currently using one of those cheap chinese 30A charge controllers (PWM), witch is black all around but has a blue front with a small display and a couple of buttons. It came as a "gift" when I bought the panels. The only things connected to the inverter are a 35'' LED TV, 150w, and all the light bulbs of the house(all LED), witch, if turned on all at the same time(witch almost never happens...) puts a load of 160w at most. The thing is, we only turn on the lights at night, shutting them down when we go to sleep. The same goes for the TV set. My mum only watches TV at night. With no load on this system during daytime, do you believe I have something to gain in changing to a MPPT charge controller? Thanks in advance.

[@silenttraveler2710]

I now crown thee William Prowse King of Solar. Love you Will, xoxo

[@Cooldipo]

All hail the king..... Long may you reign!

[@steve-o6413]

I'm recommending him to anyone who asks about Solar I'm sure his book is a great read too...

[@TatManToo57]

Very smart man! Mine is working but could always be improved on. I'll look up your site.

[@kelllylipp1041]

I've just started looking at your videos. Very nicely done! I've done 8 or so installs on various RVs since 2010. Amazing how much has changed and how much less expensive it is now and how much easier! One question regarding your comment about Chinese manufactured MPPT vs. others: are you confident that these less expensive units will actually hold up in real world conditions? I suppose if they are cheap enough you could stock an extra. But if you are relying on solar for your world and you have a failure in the dead of winter and no spare available you could have a real problem...

[@averyalexander2303]

I've wondered about that too. I've also wondered what their typical failure mode is. If they normally fail open circuit, that's obviously much less of a problem than if they frequently fail spectacularly and overcharge the batteries, possibly start a fire, etc.

[@jasonbrown467]

i finally got an mppt controller. last night i setup a test to be run today. i placed a pwm controller and a mppt controller next to each other on the bench and each controller got its own dedicated 100 watt panel and a partially discharged 12vol agm battery. when i got home from work i was able to read the watt meters on both systems and found the pwm outperformed the mppt. it was sunny but only for about an hour this morning, then became overcast but not the super thick cloud layers i normally see when its over cast, and even snowed off and on some of the day. the pwm pulled in about 206wh and the mppt pulled in 198wh. in the very first light of the morning the pwm started charging the battery for about 20 minutes before the mppt did, and i thought maybe something was wrong in my test, so i swapped cables at the controller going to the two solar panels and the pwm started back up charging and the mppt just sat there chilling. both panels are the exact same and sitting in the same position and angle in my yard. i believe as soon as i get to 200 watts the mppt will shine, as i will wire it in series which will deal with the amps much better than the required parrel connection that the pwm will require at the 60 foot run. basically series will be 36v x max 5 amps = 180 watts, and pwm will be 14.4v x max 10 amps =144 watts, minus the loss due to "high-ish amps over 60 foot run, who knows maybe i am wrong, more testing to come

[@jeremyball169]

Great video just one thing you don't mention is if you go 24v your inverter will be a lot more expensive.

[@patricknguyenbrewer2618]

You are awesome young man, I appreciated you very much, you make it easier to understand,

[@AleemAhmed]

Best Informational video for solar power! 👍👍 Totally loved it!! 💖 The way you used text and tell more information about it, that really helped alot 😊😊

[@pyronmasters]

I have two 325w panels and two 6v 225ah batteries with a cheap 1,000w $100 inverter, with a 30a pwm (both panels in parallel, it couldn’t keep my chest freezer running (overcast days my inverter shuts down), I replaced the pwm with a powmr 60a mppt (panels in series) and the batteries fully charge even in overcast days, Now I use the pwm for a portable solar generator (with an old car battery) soooooooo MPPT for daily use, PWM for emergencies (just to keep batteries full but not in use)

[@standbyme6395]

Ip68 rating. Pwm is what I bought because that is one of the only one I found for a decent price. It came with an aluminum case at 20a and a remote. No lcd though. Can use on li and la. Will be nice for outdoor conditions.

[@free2binnh]

Living in Maine, I think an mppt is pretty mandatory. I just picked up a Rockpal 300W power station from Amazon for $240, was a lightning deal for like 6 hours. There is a Chinese company selling a very similar looking box for $226, I think the name Floureon and another company, Allwei, I saw KZbin videos, possible copyright infringement.

[@enki2gold]

I will have 6 12v 100w 5.5 amp panels in series for 1 72v 390w 5.5a panel. I dont know much and im still learning. But I think with mppt ill still get a little more from the voltage conversion to bring the volts down to 24v for batteries. So ill be guaranteed 390w at 24v plus some more after the conversion. Correct me if im wrong. Might seem dumb considering I could get higher voltage panels and have less panels all together but i looked and for my layout this works.

[@russellk.bonney8534]

You are right to parallel up existing 12v system panels for PWM or wiring them in series for MPPT. You also agree that parallel~panel PWM systems can still be utilized depending on the economics. For those starting from scratch allow me to put my 2 bobs worth in... The MPPT is the way to go because it makes best use of the available sun under a wider range of conditions including solar angle. In a PWM system the 18v of your typical 12v system panel gets pulled down to the battery voltage by the PWM (basically power averaging), and ditto for an MPPT if provided in its place. So direct replacement gives no real benefit and getting the most out of an MPPT (or any benefit at all) requires you to go to typically double the 18v volts for the panels. If your MPPT can handle even higher voltage, then go up to that. For the first 18 volts or so, an MPPT acts like a PWM. If extra voltage exists (like with a 36v house panel being ideal) or WITH 18V PANELS IN SERIES, the MPPT controller has an inverter section built in (transformer and all) which converts the extra 18 volts or so (2 x 18) into current which also goes into your battery. So in a two panel 12v battery system, instead of getting say 6 Amps with a PWM, on the same same panels wired in series to 36 volts you might see 10 Amps with an MPPT. (real world figures) So if you only have 18v panels then stick with the PWM, it's cheaper. To get the best use out of an MPPT controller the system needs to be designed using 36v or even 72V inputs (within specs). *Technically the MPPT tracks and keeps to the voltage of the panels that provides the maximum power output at any given time. That's called tracking and to be precise, Maximum Power Point Tracking or MPPT. Panels in series need to be the same. (note: People can get a benefit from a direct switch over to a MPPT controller if say their panels are nominally 22v open circuit. This voltage is becoming more common than the old 18v. The state of your batteries can also cause controller power outputs to change so be aware.

[@canwelook]

My solar feed is only a concern when it's cloudy or when trees block sunlight. And that's when MPPT shines.

[@philliplapkovitch311]

Thanks thinking about building my first one and will probably opt out to spend more money on higher quality equipment and go a little larger the first time will save me money in the long run

[@Tryin2FlyII]

I am totally new to Solar and trying to find as much info as I can your videos seem very complete and have a lot of information. I know a lot about PWM and you say PWM and other times you say Pulse Width Modulation however as a noob I have never heard the term MPPT and you never say what it is? I will look it up but you might want to add that for beginners such as myself Thanks for the videos I have only watched two so far but I am SURE that will change lol Thanks

[@WillProwse]

Maximum power point tracking

[@wiredforstereo]

I would say PWM is only for very small systems for maintaining a battery or powering something small like a fence charger. I have 100W solar panel on a battery for a fence charger and a 30w panel for maintaining a trailer battery bank. But if you're actually using any amount of power, MPPT.

[@lindacreatore1628]

Excellent video Will! My friend and I are going to be setting up a solar system for our RVs and this is a great beginners vid! Thank you for your clear explanations!

[@okerehchidoziejohn3043]

I like your explanation, it's very understandable. Well done sir. Thanks

[@THEPAINOFITALL]

I’m glad this was a fast explanation

[@ReviewsandTech]

Great video in regards to MPPT and PWM, just awesome, thanks for sharing your knowledge my friend. Cheers

[@darrenbradz]

Thanks Will great advice. Mppt got it.

[@wa9kzy326]

Even raising the question of what is the threshold between PWM and MPPT chargers is most enlightening.

[@ludovicguerre9576]

In Victron documentation, they say that PWM and MMPT have similars performances with optimal sun. Seem, the difference is when the MP point is not at a "normal" position.

[@dannynova3412]

Great job! Down to the easy answers.

[@tompayne695]

Morningstars Charge Controllers last and last. I have installed them since they came out, went off the grid in 1983. Failure is an inconvenience.

[@georgemitchell4005]

I agree completely. I started with really cheap PWMs on a small scale 12V setup with LIFePo4 batteries and had nothing but trouble, I eventually moved up to Renogy controllers which were much better but still not well suited to LiFePo4s. Then I finally gave up on the economy Products and bought a Morningstar PWM. It was a world of difference. The compatibility with LiFePo4 was excellent since you can run a bulk charge beginning to end without any tapering of charge rate. They just work with no headaches and are super dependable. I now have three of them and planning to get at least one more. They are extremely flexible and easy to program. And if they ever have a problem which I doubt they ever will, you can send them back and get them repaired. Expensive yes, but in the long term they are a great bargain.

[@raycalandra1887]

As a beginner setting up a 200W solar system with a 100AH Lifepo4 battery for my RV, I appreciate your expertise and candor. I recently purchased a Renogy 20Amp Rover Elite MPPT charge controller. I am now seeing some negative reviews about its performance, but I lack the knowledge to judge the validity. Could you tell me in simple terms whether it is a good choice, or are there better chioces in the under $100 price range? Thanks for all you do.

[@mdouble100]

That's for clarifying the differences between MPT and MPPT charge controllers.

[@johnlatsch9720]

What is the out put voltage of the mppt I'm only getting 12.9. That's not enough to charge a battery

[@sponge850bobette7]

I think you do an excellent job with your videos. I appreciate it very because producing video content is time consuming.

[@reneemartinez7452]

When you're trying to get rid of ComEd electric bill nothing is boring please keep bringing on the info. Do you live out of town the Byron Illinois nuclear plant is closing because of ComEd

[@angelakelley3332]

Thank you so much for the information! I'm trying to figure out a solar system for myself and haven't gotten a lot of clear info yet but your one video cleared up so many questions for me. Thanks!

[@idsullymichaels]

great resource - thanks for all you do. VERY educational. I started researching solar just for trickle charging an RV battery for a 4 day boondock trip (water pump, LED lights, MAYBE the heater blower - but likely not)... we have a 12v lead Marine battery that does the job, but would likely be getting pretty drained. Don't feel like drilling in the roof (yet?) and we camp with hookups (usually). I thought about a small 20W trickle charge to clamp to the battery we have ($60) - to a lithium battery ($350) and a 200W Renogyn kit w/ 40 amp MPPT Rover charge controller ($340)... hmmm. $60 or $690... Even looked at the folding stuff, but those controllers seem cheap. Think I settled on the 100W Renogyn with 30Amp PWM WandererTM - I can make a stand for the panel. Maybe I upgrade the battery (says it handles all types) and maybe I eventually put the panel on the roof and add another. But I don't see us going over 2-3 100W panels or over 2 batteries.

[@unclewill]

Thank you I understand that a lot better then I have in the past

[@user-fs4fd3gv3r]

PMW more cost effective and produces more power for the cost. MPPT + 25watt panel cost the same as a PWM + 120watt panel.

[@GMCBURBAN]

PWM has the advantage of being able to use odd size panels as long as the voltage of them is pretty close. I've worked on a few setups where we could get a lot more panel area on the rv roof by selecting panels that fit the spaces available, the panels are cheaper and more than compensate for the controller style. Also seen that with PWM controllers people build in a 2nd redundant controller as a backup that can be switched in if there's a problem with the main one. One last thing, I've heard of more faulty mppt controllers than pwm, I don't mean the cheap crap ones but pretty good decent price stuff. Mppt is great for big arrays with exact match panels and pwm has no place on these setups.

[@randybobandy9828]

What? My mppt works with any Voltage panel as long as it's below 100v... I have 4 panels in series that equal 81v and it's fine.

[@DonDaly]

​@@randybobandy9828how many watts volts amps are your panels and are you series or parallel strings is your batterie bank 24 volts? And last but not least what controller do you have thanks

[@TJVergerII]

MPPT got it. Now the battery for a 2/100 watt panel in series to the MPPT. Thanks

[@opera5714]

NEVER buy battery voltage panels! You can get grid tie panels with more power at half the cost.

[@finophile]

nice summary ... I'm MPPT for all those reasons

[@johnswift1736]

I did compare both with a 18v 6.7amps. 120w panel. The cheap pwm that is all over the market at 4 dollars just wouldn't give anywhere near the 6 amps. 10amps from mppt. I am sure the pwm just doesn't give you the amps either.

[@danvantrisaitemple1647]

Thank you. I have learned a lot about solar power