Solar panels charging 3 while camping?

[RayK]

There are solar panels available which have a built-in microinverter (converts the panel's DC power into 240VAC). If enough panels are strung together, they might provide enough power (current) for the mobile connector (UMC) to charge the car, albeit at a very slow rate. 3 of the SunPower panels I've referenced below should generate about 4A in optimal conditions.

As to the refrigerator/freezer, I'm assuming that you're not talking about a regular kitchen unit but instead something like a portable / mini-fridge running off of 12VDC. The only problem I see with that is how you intend on connecting it to the car. If you use the cigarette lighter, there may not be enough power available through that outlet. An alternative would be to clamp directly onto the 12V battery but I'm not sure if the car will allow that; or more precisely, the car's power management system.

ref: https://us.sunpower.com/sites/default/files/spr-a-series-425-415-400-g-ac-datasheet-532618-revb.pdf

 

[mattack4000]

Buy a battery bank and run it separately, that way it wont go on and off while you get off for a pit stop. You can charge the battery bank with your car's cigarette lighter

 

[dhrivnak]

There are solar panels available which have a built-in microinverter (converts the panel's DC power into 240VAC). If enough panels are strung together, they might provide enough power (current) for the mobile connector (UMC) to charge the car, albeit at a very slow rate. 3 of the SunPower panels I've referenced below should generate about 4A in optimal conditions.

As to the refrigerator/freezer, I'm assuming that you're not talking about a regular kitchen unit but instead something like a portable / mini-fridge running off of 12VDC. The only problem I see with that is how you intend on connecting it to the car. If you use the cigarette lighter, there may not be enough power available through that outlet. An alternative would be to clamp directly onto the 12V battery but I'm not sure if the car will allow that; or more precisely, the car's power management system.

ref: https://us.sunpower.com/sites/default/files/spr-a-series-425-415-400-g-ac-datasheet-532618-revb.pdf

Not really as if the microinverter does not see grid power and stability they shut down.

 

[KenC]

Okay, so the general trend of the comments so far, is as expected, solar panels are not yet practical for your purpose.

Why not reconsider some of your goals? How about a nice Yeti cooler. Those can keep stuff cold for days. And do you really need to run Sentry mode, which can cost you 30 miles of range a day, or about 7kWh, or 10% of your battery a day. Seems like an expensive use of a precious commodity. Instead just get one of those motion locks for your rack.

Now, back to the fridge, if you have to have one, maybe bring a 1000w inverter generator. Those are easy-to-use, fairly quiet, and use very little gas. Fire it up, cool off the fridge, then shut it down, until 6hrs later, or so, and do it again.

 

[SammichLover]

On a nice sunny day with a good vantage point (AKA nothing to throw shade on you), for $1200 you could collect equivalent to 1%-2% of your SOC....and your trunk full of gear taking up space you could use for other essentials like a change of cloths, a couple 66ers of bourbon, etc.

Renogy 400-Watt 12-Volt Monocrystalline Solar RV Kit for Off-Grid Solar System-KIT-R400MBADV30 - The Home Depot

OR Just get a 50A plug camp site. Or use a 12V DC->AC inverter in your car to run what you want and every couple days to a trip to the nearest charger on plugshare.com.

 

[RayK]

Not really as if the microinverter does not see grid power and stability they shut down.

Ah, you're right. Poked a hole in my theory. Although I think there are panels you can use off-grid but maybe not with individual microinverters.

 

[SammichLover]

Ah, you're right. Poked a hole in my theory. Although I think there are panels you can use off-grid but maybe not with individual microinverters.

You just need something to sink the produced power in a steady manner and simulate a stable grid. That's what a battery pack like Tesla Power Wall install does. It detaches from the non-functional grid line coming into your house and then simulates the grid internal to your house's electrical panel.

 

[Tim]

Sure. This is possible. 10 flexible 160w solar panels are probably the lightest option. You'll need probably 200-400ah(2-4 car battery sized) lifepo4 batteries, beefy solar charger and a 2kw inverter. All of that will set you back a few grand and will kind of be a pain to setup, but it should do the trick. If you don't want to run sentry mode continuously your power requirements become enormously less. Refrigerator is a rounding rounding error.

You could also get something like rec370aa panels for about a dollar/watt from a supplier like realgoods.com. Those panels are much much much better than flexible panels, as well as cheaper, but they'd stack a bit higher. You'd only need 4 of those panels(they're an inch thick and 3x5 feet). Maybe add some tigo optimizers to them. In the sun 4 of those panels will get you about 5kwh /day usable after losses.

If you don't want to build the charger/inverter/battery system there are portable power stations available online that might work. Most don't have chargers big enough for what you need, but maybe try a maxoak ac200 or a Titan.

If you want to go real cheap, get 300w perc panels for 60-70¢/watt and a used ev battery module for $500. That cheap system would cost about $2k.

Good luck.

 

[mattack4000]

There is no going back to a regular cooler when you are used to a real fridge

 

[StealthP3D]

You will only get maybe 1kw per day charging if you are lucky. Goalzero cant really charge above 6 or 7a without tripping.

That's not accurate info. "Goal Zero" is not a particular product, it's a brand name. They make battery banks in a wide variety of sizes in both lead-acid and lithium-ion. I have a Goal Zero Yeti 1400 (lithium-ion) that I purchased almost two years ago. For the first half of the discharge cycle, my Goal Zero will charge my Model 3 at the full 12 amps/120V. It's only as the lithium-ion battery voltage starts to sag in the latter half of the discharge that it's necessary to reduce the charge amperage to prevent the Yeti from kicking off. When I set the car to charge at 5 amps it will bring the Yeti 1400 down to 3% remaining energy before it's too low to continue charging the car.

Goal Zero also offers the Yeti 3000 with more than twice the useable energy (3 kWh). While I haven't tested that particular unit, it should go much deeper into the discharge cycle at a higher charge amperage since it will be discharging each cell at half the rate. That unit would pair nicely with 400W of solar panels.

I use my setup as a backup emergency power for electronic devices since I can't afford to be without connectivity. I wouldn't mess with it for EV's unless the EV had a built-in solar charge controller (eliminating the secondary battery bank), especially if it would handle 1 kW of solar panels. That would make it easy to top-up the battery during extended camping in sunny weather or to maintain the battery indefinitely, even with short days and plenty of clouds.

I'm looking forward to finding out what the solar capabilities of the Cybertruck I have on order are!

 

[mattack4000]

That’s what I meant, you can’t do anything more than a Slow trickle charge. What is the point? By the time you factor in all the losses and time, you get 3 extra miles?

 

[StealthP3D]

There is no going back to a regular cooler when you are used to a real fridge

Electric fridges make sense for usage over 2 or 3 days (but only if you have a handy energy source obviously). For anything under 3 days, I much prefer the large flat ice packs such as these:

https://www.amazon.com/Lg-Zero-F-Co...1162|n182305bc707b48f3b3e0d9a8f0f17e9c03&th=1

These big bad boys are great! They are so cold you have to protect your vegetables from freezing (they work best when your freezer is a true "deep freeze" of less than 0 degrees F.). Two of them stay frozen three days in my inexpensive chest cooler as long as all the food and drink is cold at the start. And there is no mess from ice melt obviously.

 

[StealthP3D]

That’s what I meant, you can’t do anything more than a Slow trickle charge. What is the point? By the time you factor in all the losses and time, you get 3 extra miles?

As I said, I tested it and added 4 miles at a car temperature of 60 degrees. And it will charge at more than the 6-7 amps maximum you claimed. And, yes, I agree with you, for my usage I'm not going to need to mess with it. I'm just trying to keep the info accurate.

One other thing, I've never tried it below freezing but I'm pretty sure you wouldn't get much of anything in the way of charging a cold-soaked Model 3. I base this off charging off a 120V 15A outlet in freezing weather because first, it warms the battery before any real charging starts. But I can confirm, it does add miles in warmer weather.

 

[Jedi2155]

GOAL ZERO Yeti 6000X Portable Power Station and 2x Boulder 200BC Solar Panel Kit

Here you go.

6 kWh, 2 kW inverter (3 kW momentary peak), 400 watt panels.

Goal Zero’s newest battery is the "most powerful Yeti to date"

Depending on your location, use the map to multiple your solar panel by number in the legend. I.e. 400 watts of panel times a 5.75 insolation value should net you about 400w x 5.75 = 2.3 kWh of extra energy/day

6 kWh + 2.3 = 8.3 kWh usable..

 

[mattack4000]

The 1400 has nearly 1.4kw in usable power, of course you can squeeze 1+ kw into your car. My point is that if you have to charge at such a slow speed, is it really much of a solution. At 6a, it will take you 3 hours to move 1kw into the tesla. If you are lucky, you might be able to get a 200w solar to charge that much in a day!

As I said, I tested it and added 4 miles at a car temperature of 60 degrees. And it will charge at more than the 6-7 amps maximum you claimed. And, yes, I agree with you, for my usage I'm not going to need to mess with it. I'm just trying to keep the info accurate.

One other thing, I've never tried it below freezing but I'm pretty sure you wouldn't get much of anything in the way of charging a cold-soaked Model 3. I base this off charging off a 120V 15A outlet in freezing weather because first, it warms the battery before any real charging starts. But I can confirm, it does add miles in warmer weather.

 

[StealthP3D]

The 1400 has nearly 1.4kw in usable power, of course you can squeeze 1+ kw into your car. My point is that if you have to charge at such a slow speed, is it really much of a solution. At 6a, it will take you 3 hours to move 1kw into the tesla. If you are lucky, you might be able to get a 200w solar to charge that much in a day!

Like I said, I wouldn't bother other than for testing purposes. But if you're camping, the leisurely charge speed would be of no concern whatsoever.

Yesterday I was using my Boulder 200W panel to charge the Yeti with the all-important MPPT (maximum power point tracking) charge accessory and was getting up to 216 watts as the sun would clear the small white clouds. I was also getting a steady 185-192 watts with the sun in clear blue sky. The MPPT increases the charge efficiency when using solar panels by a very significant amount! The standard charge controller that comes built-in to the Yeti 1400 is cheap crap. Getting 1400 Wh's in one day with the MPPT charger is not a problem if you have good solar conditions.

 

[StealthP3D]

GOAL ZERO Yeti 6000X Portable Power Station and 2x Boulder 200BC Solar Panel Kit

Here you go.

6 kWh, 2 kW inverter (3 kW momentary peak), 400 watt panels.

Goal Zero’s newest battery is the "most powerful Yeti to date"

Depending on your location, use the map to multiple your solar panel by number in the legend. I.e. 400 watts of panel times a 5.75 insolation value should net you about 400w x 5.75 = 2.3 kWh of extra energy/day

6 kWh + 2.3 = 8.3 kWh usable..

Keep in mind, that is the average daily value over the course of a year. So, for example, here in Washington, we will get a lot less than the average on the average winter day but the average summer day will be much higher. Also, a good day that is clear will produce a lot more than the average figure from that table, summer or winter. That's why the values are so much higher down in the desert southwest (a lot more clear skies). But a good day up here can actually produce more electricity than a good day in the desert southwest.

 

[Jedi2155]

That's a good point. I"ve been researching this for the past hour since its gotten me interested to see how the consumer side of the market has gotten. Goal Zero has a pretty flexible product. The Yeti integrated MPPT while nice is relatively limited to 15-22v at 10A (which means most nice residential panels wont work).

My biggest problem with the goal zero "boulder panels" is that they're not the most efficient design.The boulder 200 panel is not particularly efficient at 2160 in^2 for 200 watts of power.I saw that they offered this option which got me curious:

• Can I use a Yeti with a residential commercial panel (which are relatively cheap)?
• Answer is Yes! But not easily.

I saw this product 30 Amp External MPPT Kit 30 Amp External MPPT Kit but you can't use it directly.....you need a power tank and this $400 piece of kit.

• Same SolarChargeController from WholesaleSolar without the cables: for $220
• Questioning on whether or not you'd need this $400 expansion module or if you can connect it straight to the anderson input
• 
• You'd just need an Anderson cable + whatever you connect to your panel.
• The other thing is residential panels are pretty damn big at about 6-7 ft long usually lol, more efficient and cheaper but yeah.

ORRRR I just wait for the damn CyberTruck and have an integrated solar panel + 240v outlet option.

 

[Watts_Up]

From my own experience, if you left any food in a car, even in a cooler or a refrigerator, the containers needs to be bear safe.

 

[StealthP3D]

That's a good point. I"ve been researching this for the past hour since its gotten me interested to see how the consumer side of the market has gotten. Goal Zero has a pretty flexible product. The Yeti integrated MPPT while nice is relatively limited to 15-22v at 10A (which means most nice residential panels wont work).

My biggest problem with the goal zero "boulder panels" is that they're not the most efficient design.The boulder 200 panel is not particularly efficient at 2160 in^2 for 200 watts of power.I saw that they offered this option which got me curious:

• Can I use a Yeti with a residential commercial panel (which are relatively cheap)?
• Answer is Yes! But not easily.

I saw this product 30 Amp External MPPT Kit 30 Amp External MPPT Kit but you can't use it directly.....you need a power tank and this $400 piece of kit.

• Same SolarChargeController from WholesaleSolar without the cables: for $220
• Questioning on whether or not you'd need this $400 expansion module or if you can connect it straight to the anderson input
• View attachment 547114
• You'd just need an Anderson cable + whatever you connect to your panel.
• The other thing is residential panels are pretty damn big at about 6-7 ft long usually lol, more efficient and cheaper but yeah.

That looks like a charge controller for a lead-acid battery bank. I don't think it would work (at least not properly). The Yeti 1400 (and I assume the Yeti 1500 which looks to follow) come with a cheap charge controller built-in or you can buy their MPPT controller which bypasses the cheap built-in controller. This is the recommended route if you will be charging with solar. These charge controllers are proprietary and they are responsible for keeping the li-ion pack safe. You can't just wire in any old brand/type of charge controller to the inputs because the charge controller must communicate with the sensors in the battery bank. The Anderson inputs input into one of these controllers and you don't want your current going through two controllers (assuming it would work at all).

I mean, you could hack it using the two proprietary high current inputs under where the MPPT controller is supposed to mount (but you would have to hack into the proprietary connectors themselves. And then you would be risking battery fires, etc. - not recommended. You also might need to hack the Yeti software because I suspect there might be a solid state relay between the power inputs and the batteries. If you are going this route, scratch build a power bank from individual cells (it will be cheaper).

ORRRR I just wait for the damn CyberTruck and have an integrated solar panel + 240v outlet option.

YES!! I hope it has inputs that can handle some serious wattage and is not limited to the rather small optional Tesla panel designed for the Cybertruck. I suspect the solar option might not be available for the first year or so.