Renogy 12 Volt Solar Kit efficeint and convenient? ?

[John61CT]

But beginners need a simple starting point, and rules of thumb can be useful for that.

The most important points for battery longevity sound simple

1. Get back to true 100% Full most cycles

2. Don't draw down below 50% except occasionally if necessary

Which can be adapted to

Don't draw down more than you can recharge every day or two.

The problem is, obeying these laws takes more knowledge and gear than most people have or are willing to acquire.

So we ballpark it for most and hope for sunny weather.

 

[GeorgiePorgie]

Thanks. Hopefully the knowledge will come with time. However, I have spent over 60 years trying to not deal with anything mechanical. I can't follow some of the posts at all. I need to have electricity from the beginning because of the CPAP machine, so ballparking it is the best for now.

 

[frater secessus]

Here is a gentle introduction to solar that may help get your head wrapped around some of it.

 

[GeorgiePorgie]

Here is a gentle introduction to solar that may help get your head wrapped around some of it.

Thanks much. That does help and is about my speed.

 

[GeorgiePorgie]

One article I read on this website said:

Q. How Much Solar do I need?

A. My simple answer is to buy all you can afford.

That makes sense to me. However, I also keep reading that it is better to figure out what you are going to need by using a formula for the things you plan on using. I have not bought any of the appliances that I will need yet, so not sure how realistic that would be.
I do have a CPAP machine, but have to find out about converting it to 12 watt power. It is a Resmed Airsense 10 and I get the idea that it will no be difficult finding a power cord to convert the voltage. I also want a refrigerator, so I am guessing about 400 watts would be sufficient. Is there any downside to having "too much" power?

 

[John61CT]

Since in a mobile context space for solar is so limited, it's good advice if you can afford it to mount as many watts as possible from the get go.

Batteries are very heavy so going overboard there has a cost beyond the money, but a bit too much is a lot bettrr than way too little.

Depending on bank chemistry there is a declining return to the size of your mains charger, so hold off on that for now, but it should be purchased shortly after the batts.



Everything else is easy

 

[John61CT]

Everything else is easy

Sorry got cut off

Everything else is easy to add to later if needed.

Don't skimp on quality of wiring, connectors, switches, circuit protection etc.

But without a good idea of the total loads, you'll always be rounding up, and the cost difference between "plenty for contingencies" vs "just enough for that" can really add up.

So, to save money, really best to define a detailed energy budget from the start.

 

[breeze]

Hang in there. It's a learning curve for everybody. If someone is constantly confusing, then you need to IGNORE them in your site's control panel, because they are wasting your precious time! Ultimately, your first system will be vendor dependent, and then you will start learning: me too.

Just don't walk into something blind because you are confused. Follow good and clear posters like Frater, until you can get a good game plan.

 

[saracatherine]

Here is a gentle introduction to solar that may help get your head wrapped around some of it.

that whole wiki is a TREASURE, a million thank yous for posting it!!!

GeorgiePorgie I really sympathize! I find this all very confusing and daunting. When it comes to certain things like this in life, I find myself telling people, “Explain it to me like I’m 5 years old.” 

(I recently watched a dozen youtube videos when doing research on how to charge a deep cycle battery. All of the videos showed how you hook it up, what you set the charger to, etc., none of them showed where the charger is getting ITS power so I’m still missing a foundational piece of the puzzle. I did eventually figure it out—sort of—but my point is it’s amazing how many how-to sites and videos assume starting knowledge that not all viewers have. I have won awards in the fields of writing and art, and I know I’m an intelligent person, but electronics, mechanics, using tools, thinking spacially...I really struggle. I don’t want those struggles to keep me in fear, so I hang around here and watch videos and read stuff and hope that the pieces will start to make more sense eventually! Hang in there!)

 

[GeorgiePorgie]

GeorgiePorgie I really sympathize! I find this all very confusing and daunting. When it comes to certain things like this in life, I find myself telling people, “Explain it to me like I’m 5 years old.” 

Agreed on the simple instructions. There are some posts that I know are good info, but I don't understand the initial concepts that I need to know or the jargon. Anyway, hopefully using a kit will make it all simpler and I do have a friend who is very handy with tools who says it would be fun to help. I'm not relying on that, but if he helps me buy a mechanically viable vehicle, that would be a major step.

 

[saracatherine]

Friends who find this stuff enjoyable are gold. I have one, too, and when I’m ready to get serious I’m going to be calling on him a lot! I just have to be careful that I still do my best to understand it myself, because I really want to be self-reliant on this front and others. It’s like learning a new language.

 

[GotSmart]

Since in a mobile context space for solar is so limited, it's good advice if you can afford it to mount as many watts as possible from the get go.

Batteries are very heavy so going overboard there has a cost beyond the money, but a bit too much is a lot bettrr than way too little.

Depending on bank chemistry there is a declining return to the size of your mains charger, so hold off on that for now, but it should be purchased shortly after the batts.



Everything else is easy

Wrong 

John61ct.  Do you have any real knowledge about this subject beyond what you read online?

A system should be balanced. If you buy too much battery and are unable to keep them charged. You just threw away money. 

PLEASE STOP GIVING ADVICE ON THINGS YOU DO NOT KNOW ABOUT.

 

[GeorgiePorgie]

A system should be balanced. If you buy too much battery and are unable to keep them charged. You just threw away money. 

 Any recommendations on the best batteries for a Renogy 400 watt kit? I rather spend extra money for convenience and simplicity, than less for a lot of hassles. Is two batteries enough?

 

[DLTooley]

CPAP's, without humidifiers as most do, are a low power draw. A 50 watt panel is plenty if that is your primary usage. My machine draws an average of 10 watts and another user here reports 4 watts at a lower pressure. There is a considerable amount of discussion on this board on that topic, just search for CPAP.

One tip for maximizing your charging ability is to turn off your 12v freezer while your batteries are in the absorption phase of charging, this will get your batteries back to close to full faster. That last bit of charging requires more time and you have extra power to run the freezer for the remainder the day while still charging the battery bank.

 

[John61CT]

No "balance" is required other than putting in more than you're taking out.

For 400W panels, between 200-400AH is fine, the more consistent your sunny days the less carryover you need.

You can find large enough batteries so only one is enough, but using pairs of Deka/Duracell 6V GCs, that translates @200+AH each to either one or two pairs.

 

[GotSmart]

No "balance" is required other than putting in more than you're taking out.

For 400W panels, between 200-400AH is fine, the more consistent your sunny days the less carryover you need.

You can find large enough batteries so only one is enough, but using pairs of Deka/Duracell 6V GCs, that translates @200+AH each to either one or two pairs.

So now you say the opposite. 

Please stop giving advice about things you do not know.  

If you are wanting a 400 watt solar input start with an inverter that can handle it. 

Get 200 ah in batteries. And 200watt in panels. You can always add solar panels to charge the batteries quicker. The 40 amp inverter can handle up to 500 w in panels. 

Almost without exception the solar problems seen here are because of too much battery and not enough panels. 


I am currently working with these systems. What do you do?

 

[Primal1]

Do the Renogy kits contain everything I need to install the system? I know I'll need mounting points and hardware but this threw me: "$1800 for 200 watts of solar and 105 AH of battery" I'm working out my budget because my wife and I will be full timing within the next few months and that's WAY more than I was expecting.   :huh:

 

[sephson]

As far as that figure goes, if you looked at my breakdown of expenses, the actual solar power system was about $440, not including the battery, which I got for free.

The foundation portion of the installation could have been skipped entirely had not wanted to at least partially conceal my panels. Had I used the mounting brackets that came with the Renogy kit, I could have saved $442 on my installation. I also would not have needed to construct an aluminum frame at a cost of $210.

Also, I purchased stainless steel security hardware, plus the tools needed to use the hardware at a cost of about $165. Use of more conventional, stainless steel hardware would probably have dropped this expense to somewhere below $50. Most of this hardware would have been unnecessary with the roof rails, crossbars and aluminum frame removed from the project.

As far as the electrical supplies go, that's an area where you don't want to skimp. You need what you need, and it's better to oversize your wiring than undersize it. That said, there are plenty of electrical suppliers with lower prices than the on I used. I used mcmaster.com because it was convenient, not because it had the best prices.

My point here is that my installation is not typical. There are plenty of areas where I could have trimmed my budget. The items I've gone over here would have shaved roughly $800 from the overall cost of my installation, bringing it down to a more manageable $1000. I also did not spend it all at once. It took me an entire year to do this, spreading the cost over an entire year. In the end, it was the nickle and dime items that got me though, as I did not properly plan for the small stuff.

 

[Weight]

I respectfully disagree with our in-house solar professional salesman, retired. I speak from my experience, yours will be different. It is a long story, but I went for two sets of EGC2 batteries for 12V-460AH. I ended with three sets,at 12V-690AH. On the roof, I have 400 watts solar panels with a 45 amp PWM controller. So you say my system can't work. This system feeds my Indel-B cooler, few lights, and 3 small fans. My 2000 watt inverter, 4cup MrCoffee, and a popup toaster. The past week I have been at 40* north. I use the microwave at most 10 minutes per day. Make one pot of coffee, and two slices of toast. I do not park in the shade, but use shade cloth to cover the hot side of my van in summer. My bank is full by end of day, unless rain, snow or heavy cloud cover. Then I reduce my energy use until recovery. I do have a 40 amp charger and generator. I like to use these once a month or 6 weeks when I maintain my bank and reset my monitor, but I often skip my schedule. I have been successful with this system from january 2017. Big battery banks have advantages when drawing high amps such as my inverter. I could easily fit 400 watts on my roof, but not more. The whole idea is to return the energy used. Not return the total battery bank capacity. That simple rule of 1:1 is not a good rule. It suggests draining the bank far too low. For van living; Mount as much solar as you can fit or afford. Have as much battery bank needed to match your use, even if over your solar size. Have more ah than you think you need is a good start.

 

[GotSmart]

I stand behind my knowledge and working experience. 

The question was about SOLAR. Not including generator. Stop confusing the questions.   

A Renogy kit will provide most of the items needed for a basic installation.  200 ah of battery to 400 w of solar is best to keep the batteries from dying in cloudy weeks.

Always hook up the panels last, and disconnect them first.