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DIY Off-Grid Solar Power

mobile-solarpower.com

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Re: DIY Off-Grid Solar Power

#171

Post by hasbot »

sandworm101 wrote: post #132

Marketing. I would take everything on this website with a grain of salt. Take it from someone who has actually built an off-grid system, one that is relied upon for 24/7/365 living rather than mere vacation cottage. For example: OP re lead-acid battery options: "Heavy, cheap, easy to use and they work! Typically will last about 3-5 years. Slower charge rates than lithium, much heavier, and they cost way more in the l…

"And, at a given price point, they can charge faster than lithium too."

Please elaborate; I have no idea what you're talking about here.

My deep-cycle RV batteries are nearly dead and I'm going to spend the $$$ to replace them w/ a lithium battery partially because of lithium's faster charging. At peak solar season, I only get about 3 to 4 hours of good sunlight on my forested property so I need batteries that charge relatively quickly.

Re: DIY Off-Grid Solar Power

#172

Post by hasbot »

neurobashing wrote: post #135

Just a (hopefully amusing) piece of anecdata: we have a squaredrop trailer, with a set of solar panels to power/charge the 12v marine battery and a pair of Jackery power banks. Most of our camping is done in the eastern woodlands: WV, PA, VA, etc. There is so much tree cover all the time. Some days, even though it's mostly or fully sunny, we're almost always at the end of some disused fire road on the wrong side of a…

Do eastern fire roads often feature fast moving creeks? I kid.

Are you able to tilt your solar panels? If they are lying flat on your roof, you won't get much power from them.

Speaking as someone that has spent the last three summers off-grid in a forest, in your situation, I'd add the ability to tilt the solar panels, reduce power consumption, and get a multi-fuel (propane and gas) inverter generator along with a propane tank. The inverter generator is a lot quieter, smaller, and lighter than generators. I don't need much power and mostly use the generator for the microwave and occasional topping off the batteries.

Re: DIY Off-Grid Solar Power

#173

Post by Solar2 »

jacquesm wrote: post #166
willprowseiv wrote: post #156

Earlier quoted context omitted.

Just because I am young doesn't mean anything. I know what I'm talking about. I started coding and building robots when I was 13, and circuit design at 15. Solar power is dead simple. Yeah I can work with raw terminals because I don't make silly mistakes. I've been working with low voltage DC for decades. Most of the systems I throw together are for educational use. Those balance wires were probably a rapid prototype…

> Yeah I can work with raw terminals because I don't make silly mistakes. This attitude will cost you dearly and is exactly the difference between being a responsible educator and someone who probably should pause to ask themselves if they are on the right track. You are setting a bad example and many thousands of people will follow in your tracks adopting your very unsafe practices as though that's the way to do it.…

Wait, you do realize I am still wearing safety glasses and following basic safety precautions, which I state over and over again. I sound like a broken record repeating this stuff. I can work with raw terminals, because I know what I am doing, and I follow basic safety protocols every single time. That is why I am not dead. If I was wrong, I would be dead. I cover safety in every video.

And yes, I hope people follow my advice more than the other channels. People on this website are suggesting people use cobalt based chemistries that have dangerous thermal runaway reactions, from recycled products, which is dangerous. And then my channel complains constantly on the importance of low temp charging disconnect, OCPD, high voltage and so much more. What am I doing wrong here? How you read my comment, makes me realize that you never did watch my videos. You really have no clue what you are talking about. Using recycled NMC cells will burn your house down, plain and simple. And people in this group who think they know what they are talking about are recommending to do that instead? What???

Yes, with authority comes responsibility, and the only reason people follow me is because I cover every single detail, and I substantiate my claims with relevant literature in the lithium ion space.

What unsafe practices!?

Re: DIY Off-Grid Solar Power

#174

Post by Solar2 »

LinuxBender wrote: post #159
willprowseiv wrote: post #157

Earlier quoted context omitted.

I usually always wear eye protection. YouTube deletes comments constantly. And leaves the spam comments. Have you not used YouTube in the last ten years? I can't stand it

I can't tell how Youtube decides what to keep and what to remove or if my comment was removed by a bot or by the channel owner. On a traditional forum a moderator would tell me if something was out of line. For what it's worth if you are the Will Prowse from Youtube I do appreciate the videos you make. Your channel has exposed me to companies I didn't know existed. The Hysolis tear-down was interesting and saves me f…

I spent an hour yesterday deleting spam, and then I get emails from long time viewers stating that their comments have been removed. I cannot tell you how frustrating it is. I try to fix this every single day, and I get my long time viewers to report the spam. Youtubes system is awful.

Thank you!! Hysolis is awesome, and with the LF inverter, you can easily work on it yourself. I am glad my videos help :) There are tons of scams online these days, and I love exposing them.

Re: DIY Off-Grid Solar Power

#175

Post by sandworm101 »

varelse wrote: post #143
bkjelden wrote: post #141

Earlier quoted context omitted.

> Look at nearly every 12v car or boat battery. You don't see those being replaced every 3-5 years. It is old reliable tech that just works. I actually do see this all of the time. In decades of owning multiple cars I've found the batteries tend to fail so regularly at about the 5 year mark that you could set a watch to it. They are easy to find and inexpensive to replace, but they absolutely do have a limited lifesp…

I would love to have found that magical car battery that doesn't die after 5 years or so. But the real comedy is that my EV is required to have one of them independent of all the lithium batteries, and if it discharges/fails, it's a whole fan dance to get into the car.

>> it's a whole fan dance to get into the car.

I've never jumped a full EV, but I have had to jump a couple hybrids after their 12v batteries ran flat. Can you not get to the 12v battery using a mechanical key? Any 12v jumpstart kit should provide enough voltage to activate the solenoid and get everything online.

Re: DIY Off-Grid Solar Power

#176

Post by quesera »

passerby1 wrote: post #150
sandworm101 wrote: post #132

Marketing. I would take everything on this website with a grain of salt. Take it from someone who has actually built an off-grid system, one that is relied upon for 24/7/365 living rather than mere vacation cottage. For example: OP re lead-acid battery options: "Heavy, cheap, easy to use and they work! Typically will last about 3-5 years. Slower charge rates than lithium, much heavier, and they cost way more in the l…

That's interesting. Winters are cold where I'm originally from, and car batteries get replaced more frequently than once in 10 years. Where are you from? Your experience is very different.

GP did not specify, but it's likely that they are referring to deep-cycle lead acid batteries, not standard car batteries.

Deep-cycle batteries are commonly used as the house power for RVs, boats, solar storage, etc.

Re: DIY Off-Grid Solar Power

#177

Post by Solar2 »

AYBABTME wrote: post #163
willprowseiv wrote: post #158

Earlier quoted context omitted.

Like what?! Can't any of you people backup your claims. It's just empty complaining on this site without evidence. It's driving me nuts. Show me what I said or have done that was wrong.

Mate, I've been following you for a while and have a generally positive opinion of you. I think you're not going to have a good experience coming here with your guns out. I watch all your videos, but wouldn't I be a fool if I just absorbed what you say as gospel? You don't do this yourself, don't you? I'm happy for you and your success and I'm very happy there are people out there like you changing their life outcome…

No of course not, I just see people on this site stating to use recycled NMC cells that are capable of burning down their house with one wrong move, then saying my videos are dangerous. I cover safety all the time, more so than any other channel I know. I do not understand why people are saying these things. I work very hard to make my videos, and people here on this site who do not understand batteries are trying to criticize me. It really makes me mad.

And thank you. Just figured out the automated banning process and am using a VPN now. I just want to respond to people, and I hope they can provide evidence of when I did something dangerous. Or said something wrong. And yes, I see what you mean about the downvotes. I am very upset right now because I could argue every point made against me here. I also allow people to criticize whatever they wish on my forum, so it makes it hard on this site where I am instantly censored if I get downvotes. It is very frustrating.

Re: DIY Off-Grid Solar Power

#179

Post by Solar2 »

sandworm101 wrote: post #154
willprowseiv wrote: post #153

Earlier quoted context omitted.

Will Prowse here. Are you kidding me? Those lead acids are kept at a high state of charge and not deeply discharged. Sure some expensive FLA can last much longer, but they are garbage. The coulombic efficiency is horrible. The internal resistance is awful. If I sold lead acid batteries, I would make way more money. You have no clue what you are talking about. And yes, when used for solar and deeply discharged, your l…

Tell that to my 12 year-old battery bank powering my family house (solar with diesel backup charge). It is a pack of deep cycle lead-acids that have served me very well. Of course they are watched and maintained regularly, and rarely ever dip below 75%. The only use case I've ever seen for lithium off-grid is for people who want to squeeze their entire rig into a closet or basement corner. And nobody ever talks about…

See, exactly proves my point. DOD is only 25%. If you do not cycle them much, you can make a lead acid last for years no problem. If you are doing 100% DOD, and do not with to deal with maintenance, and wish to have high coulombic efficiency, lithium is far better.

Volumetric density is a side benefit of lithium. We use it for coulombic efficiency, low voltage sag, high cycle life (much higher than lead acid, regardless of cycling bandwidth), usable capacity at low temperatures (much higher than lead acid! People always get this wrong), and higher specific energy. And lead acid sulfation and shorted cells require recycling. You can safely use a lifepo4 pack for years after degradation occurs. Lead acid is easier to recycle, but lithium ion recycling companies are dominating the space now. It is not like it was 3 years ago. Times are changing and there is no way anyone wants to throw out cobalt from a pack. LFP is much easier to recycle than cobalt based chemistries as well.

Re: DIY Off-Grid Solar Power

#180

Post by Solar2 »

sandworm101 wrote: post #132

Marketing. I would take everything on this website with a grain of salt. Take it from someone who has actually built an off-grid system, one that is relied upon for 24/7/365 living rather than mere vacation cottage. For example: OP re lead-acid battery options: "Heavy, cheap, easy to use and they work! Typically will last about 3-5 years. Slower charge rates than lithium, much heavier, and they cost way more in the l…

I lived 10 years off grid in vans and rvs, and now I mine bitcoin and charge my teslas with offgrid solar. I have built systems with every chemistry, even lithium polymer and LTO. And FLA and AGM. I have a lot of experience in this realm. It does not sound like youv'e seen my videos before.

Lithium packs are not a nightmare to recycle anymore. There are huge corporations fighting to recycle them now, and the tech has improved a lot. I could not say this two years ago. Lead acid is easier to recycle, but the cycle life of those packs, and sulfation you have to deal with, make them horrible for the environment. Cycling them deeply kills them fast, even the expensive ones. If you do not cycle them deeply, FLA will last for decades, but will cost a lot of money , space etc. And you need to maintain them. Lithium ion chemistries such as LiFePO4 are far superior.

I think you need to get your hands on some cells and actually build a pack. Test the coulombic efficiency and usable capacity at various temperatures and you will be blown away. And you will save a ton of money over lead acid. Lead acid is very expensive, and I would make a lot more money if I sold them. I also do not sell anything on that website, it only has affiliate links. I am not on any sponsorship contracts or have loyalty to any company. Most of my review videos are me bashing design errors and various solar companies. I do not think you have seen my videos, going by your comment. It is a little bit cringy, unfortunately.

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