Solar Generator Advice..Need feedback PLEASE!!

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bcc87's picture
bcc87
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Solar Generator Advice..Need feedback PLEASE!!

I've began to prepare and take action steps in preparation.

Can anybody offer their advice/own experience when it comes to the solar generator aspect. ?

While I have a gas generator (4000w), I want to have a solar generator..and my dilema is whether to go smaller for electonics $350 ) OR save the money and wait to go big and spend $1,500 or so to get a generator that can power appliances. 

OR it seems if there was a crisis, that maybe a few different generators may be needed like 1) the above smaller generator and then an isolated generator for the refrigerator is what Im thinking.

I'd love to hear some feedback on what has been successful on this topic with your preparation..thanks!!

Please send any links to products recommended.

 

 

robbie's picture
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You'll be hearing a lot more

You'll be hearing a lot more about these very soon. Not appropriate for every need, but take a look. They can't be beat for hassle-free installation, plug and play functionality, and comprehensive remote wireless monitoring:

http://www.indiegogo.com/projects/solar-liberator

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bcc87
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Very interesting..I'll read

Very interesting..I'll read more on these. Did you invest in the solar-liberator yourself?

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Yes, I picked up four of the

Yes, I picked up four of the 500Kw panels for a paltry $2800.00. I plan to place and monitor them on my parent's house in another state. If they perform to spec I'll buy 4 more, load up the other three slots in each panel with Li batteries and install a transfer switch so they're covered in power failures. ~4Kw should make a nice dent in their electric bill too while I monitor panel status from three states away with my iPhone. 

 

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Correction: Each panel is

Correction: Each panel is 500w, not Kw.

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sand_puppy
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Robbie, How do you plug solar panels into your house?

http://www.indiegogo.com/projects/solar-liberator

Solar Liberator with Li Batteries

1.  Are you plugging the panel directly into an outlet like they diagram?  The complexity in solar seems to be all of the devices that must be attached to the panel (each expensive, not scalable and causing loss of power) and the wiring.....  Does this system get away from some of this?

2.  How are you mounting this on you home?

3.  Where do you run the wiring from the roof mounting (I presume) into your house?

Thanks for your advice as I'm interested in this too.

Sand_puppy

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bcc87
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follow up-robbie

Hi Robbie, I echo Sandy's questions. On the surface, this product looks great as far as briding the gap between expensive solar systems vs. smaller systems that help w/ savings, no  power, etc etc.  BUT far superior to a solar generator that range $300 to $2000.

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Some questions I ask myself about this system

It looks like an interesting product indeed, on the other hand it also raises some questions:

Plugging in directly in an outlet? This seems potentially dangerous (imagine someone pulling out the plug when it is still connected to the inverter, the male pins that normally would go into the mains would be 'live'). I cannot imagine that this system would be approved using European or US standards (sometimes regulations can be useful devil). Wouldn't this set-up blow out the electronic system in the solar panel if too much load is directly connected. Maybe it just shuts the system off to prevent this. I'm no electrician, but unless you know what what you're doing, it doesn't seem like a very good idea to me...

The second is concerning pricing, how are they able to offer this system at the price they are putting it at? Maybe it's explained somewhere on their site, but how is Solar Liberator able to produce these units (which from the description and pictures look like good quality and well finished) at a price (according to their table) well below a DIY system...

I certainly don't want to discredit the system, if it works as described, these are the type of products we need more of. However, I would personally prefer to read the positive reviews of some persons who have bought and used the system before ordering...

robbie's picture
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Yes, the panels include

Yes, the panels include connectors for daisy chaining. Up to 4 panels ( maybe 6?) can be plugged into an ordinary outlet anywhere on the house. The next four ( or six ) panels can be plugged into another outlet. Obviously a transfer switch must  be added if the panels are to be used in a power failure. There is a mode switch on the device. 15 amps can't be exceeded per each ordinary outlet. The system is completely scalable. Mounting brackets are included and are easy to install if you're handy. The 30 foot power cord can be passed into the attic, or more conveniently, down the side of the house to a more convenient receptacle. These panels can operate on the ground too, or indoors wherever there is direct sunlight. I will mount mine on the roof. They also have a port for lead acid battery backup to be connected for extended use when the grid and sun are down, if one desires.

I suggest you read the comments and the FAQ section on their kickstarter page which answers all of these questions and more. They were grilled by engineers and techies for quite a while, and seemed to satisfy most with their answers.

 

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Many answers not present in

Many answers not present in the FAQ in my original link are here:

http://www.indiegogo.com/projects/solar-liberator?c=comments

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bcc87
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Picture of set up?

Thanks for message...this product appears legitimate ad sensible in pricing bridging expense solar systems to small generator products. Visually I'm wondering if mounted on roof how you rig an extension chord from roof to an outlet? Or am I missing something here?  I did read the entire website and wish they had some photos showing a typical set up. I do like have this an option in the event of an outage and ability to add to system 

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For the best cosmetic result

For the best cosmetic result you'd need to drill a hole into the attic and plug in to an attic receptacle, or run it through a small attic window. Running it down the side of the house would admittedly be less pretty, but would likely be the easiest installation. 

Another plus is the fact that you can take the panels with you to another location fairly easily if necessary.

For the reader concerned about the dangers associated with backfeeding, I agree, attention needs to be paid to what you're doing, but the device will be NEC compliant and will meet all US safety regulations. The self-diagnostics and owner alerts are quite sophisticated. I know there was some discussion of a snow melt function also which would be quite interesting.

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Photos of the panels should

Photos of the panels should be up on the site within a week or two.

bcc87's picture
bcc87
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Thanks...photos would be

Thanks...photos would be great. 

I can envision running a line on side of house to an exterior outlet..or fishing a chord through attic and fish through a interior wall. 

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And yes attic outlet would be

And yes attic outlet would be best..run through attic window. 

bcc87's picture
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When you installed for your

When you installed for your parents ...did you need to get a permit or notify pg&e?

robbie's picture
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I haven't received the panels

I haven't received the panels yet. They're still in pre-production. My comment on installation was from the creator in response to a question on the difficulty of installation, which was stated to be DIY for those with basic skills.

I'm in the northeast. The utility has blessed  the installation in concept and will be installing a new meter so we can push to the grid with additional panels when the time comes, if the shakedown run with four proves successful.

TechGuy's picture
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My two cents: I don't think

My two cents:

I don't think its a good idea to integrate the batteries and inverter electronics into the panel. The panels will get very hot during the summer mothers and very cold during the winter months. The extreme temperature swings will shorten the life of the batteries and switch electronics. The electronics will use electrolytic caps which have a fluild that will evaporate and leave the cap can, reducing its life and reduce its operating efficency.

Generally the batteries and electronics are stored in a cool basement so they maintain an optimal operating temperture. Cold or Hot batteries will also operate with reduce efficient, either by not providing the same amount of output power or not fully charge.

The power plugs are not really recommended for outdoor enviroments as moisure and water will get inside causing corrosion. This design seems appropriate for temporary outdoor use, such as camping or at outdoor events. For long term exposure, they would need a sealed connector. 

Note that the manufacure only offers a 1 year warranty on the batteries:

"The included Li-ion batteries are designed to last 5 years by the use of advanced software optimized charging cycles and thermal dissipation control. They are warranted for a minimum of one year."

 

They are also using Poly-crystaline cells instead of mono-crystaline cells:

"The high grade poly-crystalline PV cells come with 25 year warranty from the original manufacturers."

I doubt they gaurentee the power output over the 25 year warrenty period. My guess is that they just gaurentee the panels will produce some power after 25 years. Polycrystalline cells lose about 5% per year. After 10 years a 500W panel will provide only 300W. Ideally you want to buy monocrystalline panels which degrade less than 1% per year.

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I'll submit your questions

I'll submit your questions and comments to the creators. I'm interested in their answers too.

TechGuy's picture
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"OR save the money and wait

"OR save the money and wait to go big and spend $1,500 or so to get a generator that can power appliances. "

My recommendation is to save up for a more robust system instead of a tiny system. if your looking for a relable long term system, then I think your better off saving and waiting. I think better switching electronics will becoming to the market over the next two years, now that Silicon carbide and Gallium Nitride transistors are now becoming commerically available. These new transistor materials have much lower switching losses than the older Silicon designs. Its also possible that the battery technology will improve. 

If you want to you can start buying panels now as I doubt any significant breakthroughs will happen in the next 5 year or more, and its quite possible that costs for panels will increase in the future. I would recommend Mono-crystalline panels since they degrade the slowest. You could start purchasing one panel every few months or as your budget permits, and just store them until your ready to install a complete system. They will not degrade when storage in a cool dark location (basement or closet). Don't purchase the batteries until your about to install the system, since batteries do degrade, and need to be maintained with at least a trickle charger since they do self-discharge. If you let them self-discharge too deeply they will become degraded (even if you never use them).

For batteries I think the old fashion Lead-Acid batteries still offer the best bang for the buck at this time. Li-IOn and other newer designs have an improvement in wieght to power ratio, but that does matter in a stationary installation when weight isn't important. Yes Li-Ion may last longer, but they are also double or more the cost. For the same costs you can stock a spare set of dry Lead-Acid batteries that will have an even longer life (if you include 2X the life of the Lead-Acid batteries). Lead Acid batteries are less likely to develop an internal short that causes a fire. The only other batteries that I will mention is the Iron-Nickel batteries since they have very long lifecycles (30+ years). They are expensive, charge less efficienctly (~30% charging lose. ie for every 100J of energy to charge only 70Joules will be stored), Every 7 to ten years the electrolyte will need to replace (used Sodium or Potassium hydroxide which absorbs CO2 to become Sodium Bicarbonate or Potassium Bicarbonate). The advantage is that they don't degrade or failure because of anode errosion.

That said if you are planning on this for a long term reliant system because of an economic or energy crisis. Consider what happens if your inverter fails or other components of your PV system fail. You need to factor in how your going to maintain it for the long term, either by knowing how to repair the electronics or have spares available. It would really suck to pour in $5K to $10K into a system they fails six to ten months after a crisis and you have no options to repair it.

"OR it seems if there was a crisis, that maybe a few different generators may be needed like 1) the above smaller generator and then an isolated generator for the refrigerator is what Im thinking."

The problem is how you control the generator so that its not running 7/24 to maintain the refrigerator. You need to consider how to implement a system that can automatically start the generator when the temperature increases to a set threshold. and when to power it off when its the refrigurator has finished its cooling cycle. With this setup you could use a very small generator and avoid wasting fuel. Such a system could be controlled using a microcontroller (ie arduino, RasberryPi, etc) that only needs a few milliwatts of DC power. But to implement this, you'll need a generator with a remote or electric start.

If you set up an inverter with batteries system, look for controllers that can interface with a generator so that it can autostart the generator to avoid excessive wear on the batteries.

Another issue to consider is that refridgerations have AC motors which need pure sine inverters to operate correctly, Squarewave or Modified Sinewave (really modified squarewave) will cause excessive heating and poor efficiency with AC motors.

For freezers or refridgerators with freezers you want a unit that either does not have a auto-defrost or a method to disable auto-defrost since the defrosting cycle will waste energy and also reduces the storage life of some frozen food by accelerating freezer burn.

In a long term grid down, or crisis, a working generator may attract people with bad intentions. You'll need to replace the Generator muffler with one that does not produce noise that can be detected in the street in front (or back) of your property. Also set up the generator so its easy to change the oil, replace the air filter, etc. I've seen installation where the generator was installed right next to a wall that it was almost impossible to check or change the oil.

Be aware that most gasolines contain additives that accelerate degration. Gasoline fuels contain oxygenators and Butane. The Oxygenators are added to reduce emissions but speed up chemical degration that form gummy substances that can fowl carborators and fuel injectors. Butane is added to assist in spark ignition. After about 6 months all of the desolved butane will evaporate and may prevent the generator from starting in cold weather. Ideally a diesel generator would be preferred. The only issue with long term diesel storage is attack by microbes and oxygenation from the atmosphere which turned the some of the fuel into a varnish like substance. Diesel can be preserved long term with fuel additives and storing in an airtight container. Diesel is also a lot less dangerous to store since it does contain volatile compounds that can ignite with a spark.

 

bcc87's picture
bcc87
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Thanks for feedback

thanks for the feedback tech...it appears you are suggesting possibly waiting for a few years to see how the technology develops for less expensive solar? Do you think the solar generators have good value for the price of $400 for short term emergencies?www.goalzero.com/solar-generators but realize that any REAL crisis, this won't get you far, so trying to prepare/research for both scenarios. Do you have any suggestions that maybe aren't discussed above surrounding this topic?

kelvinator's picture
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My 2 Cents on Solar Liberator: Wait Till It's Real & Reviewed

Or buy something else that is. I don’t know many people with enough risk cash jingling around that they are willing to send out thousands of dollars to wait weeks/months for a product that isn’t fully tested, and not even ready to be manufactured. I’ve been involved in too many software and hardware development projects myself that, even in the hands of the most honest, talented, well-intentioned people, have gone over-budget, been delayed, had major design flaws, etc. Given that experience, I absolutely wouldn’t pre-order an unmanufactured product with a new functionality set from people I don’t know simply because the features and price points sound attractive.

From the Solar Liberator website:

"Although we have come to the end of the [money raising] campaign - a lot more work is just beginning. We have shifted our focus completely on to the development and manufacturing of the product [!?!?]. In the next week or so we will be completing the pre-production test units. We have scheduled visits to our suppliers and manufacturing plants in China in anticipation for the tooling process to begin."

As it is, I don’t want to risk my savings on most stuff that is already out from well known manufacturers unless it has great reviews from people who’ve already used it. Based on my tech experience, I’d rather buy the best stuff after it’s been successfully tested by real people in the real world and it’s just being dropped in price or sold used to make way for the latest bleeding edge technology just coming out that someone else wants to pay top dollar for. We put a 5 KW PV solar system with battery back-up on our house, and got Sharp panels partly because they had great reviews/performance, partly cause they were low priced, and partly because we figured Sharp had at least a crack at staying in business long enough to honor their 25 year warrantee. I’ve been really happy with the system, which reduced our total electrical costs to $8 for its first year in service, and probably will make us a little money this year.

I’d be interested to find out what people’s experience with the Solar Liberator systems are once they’ve been out awhile, though, assuming the project completes successfully.

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Plus my 2 cents

I agree with Kelvinator. 

I have 2 solar systems. I went with Outback and Enphase because they are known and tested, also used sharp panels. Unless you are smart enough to develop the new technology yourself, I'd recommend going with something mainstream. I installed 2 systems myself and the learning curve was huge. But both systems have been trouble free for over 2 years. 

Also....in construction I have a policy not to give "up front" money to anyone. If they can't fund the startup and get materials, then perhaps they don't have a solid business model.

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2 Cents More

Here is a great article showing some technical reasons why this system probably will not work.

http://wp.josh.com/2014/01/07/not-another-fake-plug-in-grid-tie-solar-sy...

TechGuy's picture
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"Do you think the solar

"Do you think the solar generators have good value for the price of $400 for short term emergencies"

No. For Short term emergencies a gas, natgas, or diesel generator will offer the best bang for the buck or Euro. With a PV/Battery system you need to invest considerably more money and time to match the performance of a generator. 

For long term crisis, Solar has advantages. If fuel become difficult to obtain then your not going to be able to run the generator after your fuel stocks become depleted, unless you set up a wood-gas system that will let you burn solid fuel (biomass/coal). Solar also has the advantage of silent running and is less likely to attract attention to yourself, assuming your panels are installed so they can't be seen by the road.

FWIW: I do own a portable goal-zero 25W monocrystaline panel for camping for use in a get-home bag if a disaster unfolds while I am away from my home. The 25W panel is enough to charge small portable devices like a cell phone, ham radio, gps, etc.

".it appears you are suggesting possibly waiting for a few years to see how the technology develops for less expensive solar?"

Yes and no. I think better inverters will be available on the market as better switching transistors become available on the market (ie SiCarbide, GaN). I doubt these will reduce the costs of the inverters, but make them more reliable and efficient. I don't think we will see any significant improvements in solar panels in the next few years, and its quite possible that cost of panels increases as non-profitable panel manfacturers go out of business as gov't cut back on solar subsidies. If your planning on installing solar for a long term crisis then it might be a good idea to start buying panels. Just buy and store until you're ready to commit to a complete system and installation. Battery technology may improve slightly, but I don't see any major improvements happening anytime soon. I don't recommend buying batteries until your ready to install. I would recommend buying the batteries after you have all of the other components purchased.

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These look way too flimsy

I agree with all the comments above with regards to adopting a wait and see approach with this system.  Another consideration is that the design of these panels is very suspect.  The website claims they weigh about 45 lbs each.  They are roughly 4 ft x 8 ft in size- or close to a typical solar thermal glass panel.  However, a typical solar PV panel weighs 35-40 lbs and is about 3.5 ft x 5.5 ft in size.  So the back up panel has about 50% more surface area, includes an inverter and a battery but only weighs 15% more than a standard PV panel.  The reason a PV panel weighs to much is that they have a lot of glass and a fairly rigid aluminum frame to keep them from flexing.  Monocrystalline and Polycrystalline cells do not like to flex, if they do they are subject to micro fracturing which will result in early failure.  Note that most solar PV modules have 25 year warranties.  How many products do you know of that make this claim?   So, I don't see how the back up modules have anywhere near the structural integrity to last.

If you are really interested in these modules, then buy some of the smaller ones when available and play with those.  If you want a real battery back up solar system, then you are going to have to pay real money to get something that will last.  If all you want is inexpensive power back up, then buy a gas generator.

FYI, I have a 5 kW Solar PV System with Enphase micro-inverters.  I may add battery back up at some point, but don't see the urgency and will wait for battery technologies to improve as they are the one area with the most potential for near term change.

robbie's picture
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I spoke to one of their

I spoke to one of their engineers today. They should respond to some of the questions raised within 24 hours. I wouldn't beat the product up too badly just yet.

kelvinator's picture
kelvinator
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Robbie, the Product Doesn't Exist Yet

So, there's nothing to beat up.  The point is that these are questions that can't actually be answered until it's a real thing.   For example, they might have a plan/explanation why it can be 50% larger, include more components, weigh only 15% more and not be fragile in spite of being made of brittle crystals in a frame that can be hung on windy roofs.  Until people are using the various sized units successfully in a variety of conditions, we won't know whether the engineers' ideas will turn out to work in practice.  They don't call it the bleeding edge of technology for nothing - in my experience, you don't want to buy the first version any new tech product before they work the bugs out, even from a well-established company, which this is not.  But if you want to take a flyer for fun, that's fine.  I guess some people play the ponies and stocks, some people technology and panels ;-)

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Tech is this good value...

Great feedback...

Tech...is this a good value for emergencies for my electronics, etc.? I do have a 4000w gas generator already. 

http://www.goalzero.com/p/144/escape-150-solar-kit-with-light

FreeNL's picture
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I think the best bang for the

I think the best bang for the buck with solar is to install a water preheater tank into your existing water supply. Its simple tech and it works. If you get a charge controller it makes a great dump load and you can still use emergency power when necessary with a cheaper inverter and a small battery.

1) lithium batteries are worth it. They are safe and last a long time. 10 amp hours is cheap and reliable. These giant battery farms are crazy expensive and need frequent replacement. They can are also be very dangerous especially if the battery isn't sealed. Lithium is safer and more reliable.  Batteries are the weak point in solar systems. 

2) 12-24 volt heating elements are pretty cheap and last a long time. You can also the 120v if you tie in your inverter  but why tax the inverter if you don't have to. Without the inverter your 120v element wont be worth the effort unless your system has a higher voltage (48+ volts)

3) grid tie is expensive and will decimate the efficiency of your purchase. Your heating your water anyway and paying for it, its cheaper to do that instead.

4) solar system are terrible when used for ambient heat generation. It would require far to many batteries. Its better to passively warm water in an insulated tank and use a small battery to power emergency situations such as lights and small appliances. Get a woodstove to heat your house.

5) Dont get a residential electrician to help unless they are trained in solar systems. Most industrial electricians could do this work pretty easy. Dont do it yourself.

6) the new age of battery powered tools is very good. I have a good 20v dewalt set that wont quit (ive been using the drills to drill 1/2 inch holes through 1/4 inch steel on ships. ). and i have a battery powered chainsaw thats (in my opinion) better than my husquavarna i paid a fortune for. They are cheap now  and can can be recharged with your emergency setup from above very easily. You can cut wood for your woodstove without gas. These tools will last you years if taken care of.

7) Electricity is very dangerous and requires respect. Figure out what you want and get help. What i think may not necessarily be the best system for you.

8) Dont get any ideas of "Grid Tying" anything on your own. You do not want to start the apocolypse early.

These are just some ideas and my opinions.They may not be reasonable for your situation. Get the help of professionals. Ive said that a thousand times on purpose :)

 

 

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sand_puppy
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Cutting firewood post peak oil

I have been wondering how to heat my home with wood in an environment where gasoline is not available.  It is inconceivable to me to prepare firewood without a chain saw.

FreeNL wrote:

[T]he new age of battery powered tools is very good. I have a good 20v dewalt set that wont quit ... and... a battery powered chainsaw that's (in my opinion) better than my husquavarna [gas powered chain saw].

Do you mean something like this one?  (I couldn't find a Dewalt battery powered chainsaw.)

Ryobi - 12 In. 40-volt Lithium-ion Cordless Electric Chainsaw with Battery & Charger

So how would your recharge this off a solar system?  I need enough details to locate and price the components, buy the equipment and then hook it all up.

FreeNL, if you would, could you please link to specific Li batteries you like and have experience with and how you recharge them off a solar PV system.  A set of schematics and specific products would be greatly appreciated.  Thanks.

 

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