Portable Solar Panels

[DrPrepper]

I was reading another thread that mentioned portable solar panels. I have been looking at them on Amazon. I see a lot of choices. I see most of the suppliers want to use recharging your laptop or cell phone as a selling point for getting one of these. I got a solar cell phone charger. It works great. I am wondering what these larger ones would be useful for if you found yourself in a prolonged power outage?

https://www.amazon.com/SUAOKI-Charg...10&keywords=portable+solar+panels+for+camping

I did read that they have a solar generator that can store power so that you have more options, but what options are we talking about?

 

[Robinjopo1]

I was reading another thread that mentioned portable solar panels. I have been looking at them on Amazon. I see a lot of choices. I see most of the suppliers want to use recharging your laptop or cell phone as a selling point for getting one of these. I got a solar cell phone charger. It works great. I am wondering what these larger ones would be useful for if you found yourself in a prolonged power outage?

https://www.amazon.com/SUAOKI-Charg...10&keywords=portable+solar+panels+for+camping

I did read that they have a solar generator that can store power so that you have more options, but what options are we talking about?

I was hoping for posts, because I've been thinking of solar panels too. Someone mentioned the difficulty in disposal of them

 

[Brent S]

I got a 100w panel for the camper recently. I made a simple set of adjustable feet to make it portable and flexible to change the angle to catch the most sun. The panels are a lot more economical than even two years ago, and generate however much power you need, by adding multiple panels together. That’s the easy part. Next you need a charge controller. Again still reasonable and easy. Now, for the fun part. You need a way to store all that free electricity you have harvested from the sun. Batteries are the heart of any solar system, and the most expensive part. I have two 100amp hr batteries wired together. Good enough to use for minimal camping needs for three days or so. With conservation and good days of sun I can prolong that a lot, but am being conservative here. Of course that isn’t even thinking about a heater or AC unit though. After the battery you need an inverter to change the DC voltage to AC, which most appliances use. These can be a little pricey depending on the size but again is not too bad. Back to the batteries, something to consider is the longevity of the ones you buy. I got AGM batteries, kind of to experiment with, and due to them being on sale at the time. I should get three years out of them. There are several types of batteries but some are really pricey. So, I guess the first thing you should consider when thinking solar is what do you want to run? Then you design a system that can handle the load you need to run that. Then you look at your budget and decide what you really need to run.... I met a guy that had a professional company put in his system to run his whole house. He spent over 35k to not have a power bill. If you do the math, you can bank that money and buy electricity much cheaper. Now if you’re like Arcticdude and don’t have lines near your property then you look at it differently due to necessity. I really like the independence of having your own system, but it isn’t without maintenance or risks of failures too. I will install a system on the house sometime this year and will do a detailed post as I go, so yes I think it is worthwhile but just wanted to share the little I have learned so far.

 

[Arcticdude]

I use an 85 watt portable solar panel at my pump house for keeping the deep cycle generator battery charged. It's a very simple system. There's just the panel and charge controller. It also came with a 100 watt inverter, but I haven't connected it yet. I also keep a 110 v battery charger connected to the battery during winter.
A simple system like this is very scalable. You can add additional panels, batteries and a larger inverter if more power is needed.

 

[DrPrepper]

I use an 85 watt portable solar panel at my pump house for keeping the deep cycle generator battery charged. It's a very simple system. There's just the panel and charge controller. It also came with a 100 watt inverter, but I haven't connected it yet. I also keep a 110 v battery charger connected to the battery during winter.
A simple system like this is very scalable. You can add additional panels, batteries and a larger inverter if more power is needed.

How do you (or can you) use the power for a normal plug in device like a space heater, microwave, or fan?

 

[tmttactical]

First and foremost, Solar is not viable from a pure dollar value. I ran the number for my son in San Diego and even with the rebates and incentive, plus the high cost of electricity in San Diego, it was a no-go from a pure cost analysis. yes solar panel do require special disposal techniques and I am sure the government will find a way to tax folks in the future. So figure a whole house system installed, costs $40,000,when all said and done and will most likely have to be completely replaced in 30 years, plus the batteries will not last 30 years, so your are most likely looking at a $50,00 to $60,000 system over of the life span. So what has your electricity cost you in the last 30 years?

For the comfort of being self sufficient point of view, it was the most viable alternative. Now for an off grid situation it is the only way to fly.

 

[Kevin L]

I have a small solar powered battery charger that costs less that $50.00.

I've got things like flashlights, radios, andhave been hunting for a small DVD player that runs on batteries ('D' hopefully) so I can use my rechargable lithium batteries to keep things going.

I won't have my AC powered off of D batteries, but my scientific calculator, multiple flashlights, radios, and pistol-mounted weapon light/laser combo can be kept up and running.

I've even found a battery pack that can plug into my phone, so I got that covered too.

Best of all, my stuff is all man-portable, so I can keep things running while I'm on the move . . . and small enough to stash in a hurry if the government jackboots come knocking at my door to take my stuff in accordance with emergency decree.

And by the way . . . a scientific calculator can help you with time keeping (if you know astronomy), calculating calories and resources, costs vs. benefit problems, projectile problems in long-distance sniping, drug dosage calculations, estimating mileage vs. available fuel, calories consumed vs. activity requirements, navigation with magnetic north deviation, and so on.

 

[Arcticdude]

How do you (or can you) use the power for a normal plug in device like a space heater, microwave, or fan?

I wired my pump house for 220 for the pump and 110 v for lights and outlets. And all is connected to an 8500 watt generator. So the only time I have AC power at the pump house is when the generator is running. For heat I installed a ventless propane heater to keep the pressure tank from freezing.
The house, cabin and shop are on 100% solar, but the well is over 1/4 mile away so it needs it's own electric system.

 

[Brent S]

How do you (or can you) use the power for a normal plug in device like a space heater, microwave, or fan?

To run normal AC devices an inverter changes the DC battery power to AC. So the panels charge the batteries, then the inverter makes usable power from them for your devices. The problem is two devices you mentioned are energy guzzlers. The microwave and heater. Not only do you need a system big enough to produce enough power, but you don’t want to drain your batteries more than 50% on average, or it shortens their lifespan. So you need to double your battery capacity. The microwave is doable, but the heater, I would find another backup heat source like wood, kerosene or propane.

 

[Robinjopo1]

How do you (or can you) use the power for a normal plug in device like a space heater, microwave, or fan?

Things like microwaves suck power like crazy. Really not worth using them. My propane generator booklet says microwaves are a great waste of energy. Warm stuff the old fashioned way.

 

[OldCoot]

I was reading another thread that mentioned portable solar panels. I have been looking at them on Amazon. I see a lot of choices. I see most of the suppliers want to use recharging your laptop or cell phone as a selling point for getting one of these. I got a solar cell phone charger. It works great. I am wondering what these larger ones would be useful for if you found yourself in a prolonged power outage?

https://www.amazon.com/SUAOKI-Charg...10&keywords=portable+solar+panels+for+camping

I did read that they have a solar generator that can store power so that you have more options, but what options are we talking about?

I mentioned in that thread, if it is the discussion you referenced, that the portable solar panels are a good start. They come prewired to charge most small devices. For me, that would mainly be my iPhone & USB lights. That 60 w folding panel, IMO, is not much of a step up and would not power too much.

An intermediate option between such a portable charger and a whole house solar system would be using solar generators, as you mention, such as my two Humless. One of my 280 w solar panels can charge it in a few hours. If cloudy, I attach 2 panels to it. Not cheap but oh so simple. The charge controller, inverter & lithium battery is in one light, sleek unit. These units and a flex well pump that can run directly off of solar panels are my way to survive a crisis and still power some devices/appliances. https://humless.com/emergency-power/

Unless you are planning on being on the move after a crisis, IMO one should start buying full sized solar panels & associated gear. You get more bang for the buck & can grow your system with time. Some product can be run straight from a panel, with no controllers, inverters or batteries... such as my well pump or my dc elements that can be inserted in hot water tanks. Otherwise you can build your own methods of converting & storing the solar power, as many do. Me? I'm too stupid for that so I went the solar generator route.

One appliance my solar generators will keep powered is my 50 Quart ARB refrigerator Freezer. That freezer pulls very little amps and can run for a couple of days off a solar generator without a recharge. It uses .87 amps/hour which is a bit over 10 watts per hour. That ain't much. During a crisis, I plan on keeping it running nonstop. Here is some info on my .64 kwh unit. My second unit is just a bit bigger but has double the output... 1.3 kwh.

• The 0.64kWh 1500W generator has a 640 watt hour capacity. So if you are using something that requires a full 640 watts constantly, this generator will last one hour on a full charge. Here are the results we have found testing various electrical devices using this generator:
  • Fridge: 3 hours with door closed
  • Freezer: 6 hours with door closed
  • Laptop: 12 hours
  • Tv: 6 hours
  • Washer: 2 hours
  • Lights: 6 hours

How to charge it / How long does it take to charge?

• Solar - about 3-4 hours with three 100W panels
• Plug into the wall - about 2.5 hours to charge

 

[Duncan]

Back in the 80's when photovoltaics (PV) were going hot and heavy because of the tax breaks, I was working as a systems engineer for a company called Solavolt International in Arizona. The number of vendors has risen and fallen, PV module efficiencies have gone up and down, but most of what I learned and did on some of my remote projects, (both domestic and overseas) remain the same.

Here are a few things to think about:

1. Balance of Systems (BOS) is equal to about half of your costs. BOS is everything that isn't the modules themselves, charge controllers, support structures, wiring, and batteries.
2. Even today, lead-acid batteries are the most cost-effective approach, factoring in that you shouldn't discharge them more than 35% and have to replace them every 5-7 years.
3. It's usually cheaper to buy DC appliances. Inverters cost a lot and their efficiency isn't quite what they advertise at. Plus, DC radios, televisions, water pumps, even refrigerator/freezers are built more efficiently than household-quality AC ones.
4. Mister Resistive Heating is not your friend. Use small LEDs for lights and don't even think about cooking with electricity. You can prepare 90 percent of your meals with dutch oven cooking, including baking bread, cakes, pies, etc. propane's cheaper than electricity, and charcoal briquettes are cheaper than propane. AM/FM/SW radio? Yes. TV? huh-uh.
5. The one thing you must have, if you don't want to die, is reliable potable water, I have developed submersible DC water pumps whose flow capabilities are linear: the more sunlight, the more it pumps. Forget about batteries for your waster-pump; use a direct connection from your modules (via the diode, of course) to your pump. Let it pump constantly at 2-4 gal/min into an elevated tank and let our old friend Mister Gravity deliver the water when you need it. A DC motor running a jack-pump will work, as long as you keep the output to below 4-6 gal/min.
6. If you're looking for a way to determine how much PV you'd need for enough water delivery for your homestead, let me know; I've developed spreadsheets to help you figure it.
7. Finally, think carefully about a refrigerator/freezer if you're planning on a complete PV setup; an R/F eats a lot of electricity for what you get. The only time anyone really NEEDS an R/F is if his life depends on keeping a lifesaving drug like insulin frozen.

 

[Brent S]

Back in the 80's when photovoltaics (PV) were going hot and heavy because of the tax breaks, I was working as a systems engineer for a company called Solavolt International in Arizona. The number of vendors has risen and fallen, PV module efficiencies have gone up and down, but most of what I learned and did on some of my remote projects, (both domestic and overseas) remain the same.

Here are a few things to think about:

1. Balance of Systems (BOS) is equal to about half of your costs. BOS is everything that isn't the modules themselves, charge controllers, support structures, wiring, and batteries.
2. Even today, lead-acid batteries are the most cost-effective approach, factoring in that you shouldn't discharge them more than 35% and have to replace them every 5-7 years.
3. It's usually cheaper to buy DC appliances. Inverters cost a lot and their efficiency isn't quite what they advertise at. Plus, DC radios, televisions, water pumps, even refrigerator/freezers are built more efficiently than household-quality AC ones.
4. Mister Resistive Heating is not your friend. Use small LEDs for lights and don't even think about cooking with electricity. You can prepare 90 percent of your meals with dutch oven cooking, including baking bread, cakes, pies, etc. propane's cheaper than electricity, and charcoal briquettes are cheaper than propane. AM/FM/SW radio? Yes. TV? huh-uh.
5. The one thing you must have, if you don't want to die, is reliable potable water, I have developed submersible DC water pumps whose flow capabilities are linear: the more sunlight, the more it pumps. Forget about batteries for your waster-pump; use a direct connection from your modules (via the diode, of course) to your pump. Let it pump constantly at 2-4 gal/min into an elevated tank and let our old friend Mister Gravity deliver the water when you need it. A DC motor running a jack-pump will work, as long as you keep the output to below 4-6 gal/min.
6. If you're looking for a way to determine how much PV you'd need for enough water delivery for your homestead, let me know; I've developed spreadsheets to help you figure it.
7. Finally, think carefully about a refrigerator/freezer if you're planning on a complete PV setup; an R/F eats a lot of electricity for what you get. The only time anyone really NEEDS an R/F is if his life depends on keeping a lifesaving drug like insulin frozen.

I like your point about DC appliances.. I have looked at the costs of then and kind of dismissed them due to their high costs. When you factor in the cost and short lifespan of batteries it looks a lot better. I also know that in the real world the 5 to 7 year lifespan of lead acid batteries isn’t realistic. With age they loose capacity, which just makes your point even more valad. I will look more into the appliance end with a lot more openness now. I wonder if any other countries have developed DC appliances more than we have. Sometime over this coming year I am going to make a change over to solar. I would have done it earlier if not for the battery expense. Really good post!

 

[bigpaul]

I have 2 questions:
1. just how portable is a portable solar panel?
2. a solar panel glinting in the sun will give away your location which you may not want known, I know of someone this happened to, how do you stop this happening and still get your solar power??

 

[Arcticdude]

I like your point about DC appliances.. I have looked at the costs of then and kind of dismissed them due to their high costs. When you factor in the cost and short lifespan of batteries it looks a lot better. I also know that in the real world the 5 to 7 year lifespan of lead acid batteries isn’t realistic. With age they loose capacity, which just makes your point even more valad. I will look more into the appliance end with a lot more openness now. I wonder if any other countries have developed DC appliances more than we have. Sometime over this coming year I am going to make a change over to solar. I would have done it earlier if not for the battery expense. Really good post!

I also looked in to DC appliances and dimissed them as being too expensive and not enough options available. I figured that it was better to go with regular appliances and just add more panels and batteries. Most new appliances are pretty energy efficient now days too. On our system we'll have 2 chest freezers plus the refrigerator/freezer in the kitchen. The cook stove, clothes dryer, tankless water heater and backup furnace are all propane.
Our well is 1/4 mile away so it's on it's own generator system. Next summer I'll drill a new well close to the house and connect the pump to the solar system.
Currently our solar electric system is powering the cabin, shop and chicken coop. I have been very pleased with this system. Zero problems so far. This time of year the generator automatically kicks on about twice a day to keep the batteries charged. We're going through about $60 a month in diesel.

 

[OldCoot]

I have 2 questions:
1. just how portable is a portable solar panel?
2. a solar panel glinting in the sun will give away your location which you may not want known, I know of someone this happened to, how do you stop this happening and still get your solar power??

Size would depend on which you order. My Goal Zero Nomad 20 unfolded is 30.5" x 13" x 1". Folded it is 8.5" x 13" x 1".

Regarding the glint off a solar panel, how would that glint be any different than any glint off of anything shiny in the environment... be it a car, window, water, ice, etc.? Reflective surfaces are everywhere. I think it also important to realize not every single second, during every possible crisis, will we have to be concerned about giving our location away. But if you are concerned, you can block the view by the placement of the panel. In an urban environment, you could put the panel behind a car, so that it can't be seen from the street. In a rural environment, have a screen of trees or bushes.

 

[bigpaul]

Size would depend on which you order. My Goal Zero Nomad 20 unfolded is 30.5" x 13" x 1". Folded it is 8.5" x 13" x 1".

Regarding the glint off a solar panel, how would that glint be any different than any glint off of anything shiny in the environment... be it a car, window, water, ice, etc.? Reflective surfaces are everywhere. I think it also important to realize not every single second, during every possible crisis, will we have to be concerned about giving our location away. But if you are concerned, you can block the view by the placement of the panel. In an urban environment, you could put the panel behind a car, so that it can't be seen from the street. In a rural environment, have a screen of trees or bushes.

i'm more concerned about a SHTF societal collapse type situation , in which case I wouldn't want people who don't have power to know that I do.
wouldn't a screen of trees block the sun getting to the solar panel?
if the crisis is minor or short lived then I possibly cannot justify the expense, a bit like radio's.

 

[OldCoot]

wouldn't a screen of trees block the sun getting to the solar panel?

Doesn't have to. The point of stealth is to block the view from a given point of view. I have a pasture that is totally surrounded by trees and you wouldn't know it was there unless you walked thru the trees. That doesn't mean the pasture is completely shaded... just hidden from view. A panel could be inside your fenced in backyard & be completely hidden from view from the outside. Just because your yard is fenced in, doesn't mean it gets no sun. Make sense?

i'm more concerned about a SHTF societal collapse type situation , in which case I wouldn't want people who don't have power to know that I do.

That is the beauty of solar. It has no moving parts to break and is silent. Modern panels look just like regular roof shingles. You can make solar as stealthy as you wish, by choice of location or product.

Tesla solar roof:

 

[bigpaul]

i'm not totally convinced this is something I either want or need, have a friend in another county who has a small solar panel, a small residential wind turbine and a small water wheel on a stream, only powers her lights, and her computer, for a few hours every day, no freezer, no fridge-she's a vegetarian so no meat is consumed or stored.
i'm just exploring the theory of this, don't have the storage area for batteries or large items.
i'm not one of these people that must have power at all costs come what may.

 

[OldCoot]

i'm just exploring the theory of this, don't have the storage area for batteries or large items.

The point of my comments is to show a prepper can use solar and not go full bore. That little Nomad 20 is perfect to keep a phone charged or maybe a light. Just that can help a lot during a crisis. Then you can step up to a portable solar generator and a larger solar panel and power even more. Neither requires heavy storage batteries or anything really large. The pic shows the size of my solar generator.