How to Live on 100 watts of Solar

[duckwonder]

Yes, but where are you on the continent!

Winter in Yuma at sea level is a whole different ball game than say, winter in Flagstaff at 7,000. ft.

Also, it's important to know what those needs actually are!

Do you need a Cpap machine, are you trying to run a 12V compressor fridge or are you using a cooler?

How one lives on a 100 watts of solar can only be determined with a little bit more information or else it's all useless speculation!

I agree with you for the most part, was just trying to keep it as simple as possible.  Let's assume it's Quartzsite.  I said people have what they have and need what they need so that folks don't need to totally go off of a hypothetical scenario.  If someone can run a CPAP and other things, awesome.  For someone else, they may use it differently.  That's sort of the point I guess is to see what people can run with this level of power on sunny winter days when the days are shorter.  Thanks for mentioning.

 

[duckwonder]

I'm a newb at this stuff but let me give it a go...

Each of these devices provides the power expectations a little differently, so the path to Amp-hours varies:

Indel-B TB-51 fridge... spec sheet says avg 240W/day (=240Wh?) -> on 12v = 20Ah per day
LED lights... rated at 3W, assume 4hr/day = 12Wh = 1Ah per day
ShurFlo 3gpm pump... 7.5 amps, assume .5hr/day = 3.75Ah per day
Cell phone x 2 = 10Wh (based on Google search) = 1Ah per day

So my total would be roughly 310Wh or 26Ah per day. A single 100Ah battery should be sufficient. Without doing the calculations, a 100W panel should be able to replace 300Wh per day. (I live in southern CA for now so I've got that on my side.) The fridge is the biggest consumer and that is a total approximation, but since it's winter I'll just assume the generic spec is on the safe side.

It should be noted at this point that I'm in the middle of building this stuff right now, I've yet to order my solar system, and I have no real world experience (yet!) to inform the information listed above! I assume I've overlooked some things. 

Be kind.

For new, you're way ahead of me buddy.  Hats off to you.  Thanks for participating.

 

[highdesertranger]

as far as a RV water pump goes it only draws power when it's running. with a good system(no Leaks and a accumulator tank) you can leave the switch on and it will only draw power when a faucet is opened. however it is best practice to turn the switch off when not in use. highdesertranger

 

[Boyntonstu]

I'm a newb at this stuff but let me give it a go...

Each of these devices provides the power expectations a little differently, so the path to Amp-hours varies:

Indel-B TB-51 fridge... spec sheet says avg 240W/day (=240Wh?) -> on 12v = 20Ah per day
LED lights... rated at 3W, assume 4hr/day = 12Wh = 1Ah per day
ShurFlo 3gpm pump... 7.5 amps, assume .5hr/day = 3.75Ah per day
Cell phone x 2 = 10Wh (based on Google search) = 1Ah per day

So my total would be roughly 310Wh or 26Ah per day. A single 100Ah battery should be sufficient. Without doing the calculations, a 100W panel should be able to replace 300Wh per day. (I live in southern CA for now so I've got that on my side.) The fridge is the biggest consumer and that is a total approximation, but since it's winter I'll just assume the generic spec is on the safe side.

It should be noted at this point that I'm in the middle of building this stuff right now, I've yet to order my solar system, and I have no real world experience (yet!) to inform the information listed above! I assume I've overlooked some things. 

Be kind.

How does your [font=Verdana, Arial, sans-serif]Indel-B TB-51 fridge perform as a cooler if there is no power?[/font]

[font=Verdana, Arial, sans-serif]Just curious because 5 day coolers are also pretty expensive.[/font]

 

[DLTooley]

I am attempting to run a cpap and a 40 liter compressor fridge off of 100 watts. First attempt was a fail, but I am tweaking my system incrementally and increasing my education.

The Walmart 5 day bear resistant coolers have the best price point.

 

[frater secessus]

This is my favorite kind of puzzle.

I have a list of folks running various sized solar setups, including 100w.  If it were me (and I had a 60w panel before on my truck shell):

• small, hyperefficient 10A mppt controller like a Genasun 
• non-crtical loads moved to times when there is surplus power
• minimized losses with quality connections/wiring
• only LED lighting
  off the top of my head

 

[HumbleBeginnings]

How does your [font=Verdana, Arial, sans-serif]Indel-B TB-51 fridge perform as a cooler if there is no power?[/font]

[font=Verdana, Arial, sans-serif]Just curious because 5 day coolers are also pretty expensive.[/font]

I don't know yet. I just got it last week and I'm building my cabinets and electrical system now. I'll have to get back to you on that in the future!

 

[Boyntonstu]

Idea of using a single panel with an extension cord:

We are in hot Florida and as everyone know parking in the shade and especially under a tree is much cooler than parking in direct sunlight.

"Leaves help turn down the thermostat. They cool the air through a process called evapotranspiration. Evapotranspiration is the combination of two simultaneous processes: evaporation and transpiration, both of which release moisture into the air."

The transpiration of a tree results in about a 15*F temperature drop,

What I suggest is to park under a tree or in shade and place your single panel away from your vehicle in the sun.

A simple stand will allow you to direct the panel in both direction and at the best angle to absorb the most energy.

 

[jonsun]

Agreed except its already mounted. Which is good for being out and about and still charging. I think she needs the $180 suitcase. Then she has the best of both worlds for a minor investment. They both will stay plugged into controller so all that is needed is to drag out the suitcase. Then in the dead of winter both can be set out at once when its really needed.

If space is an issue theres a 100w suitcase at solarblvd for $130

 

[Boyntonstu]

Agreed except its already mounted. Which is good for being out and about and still charging. I think she needs the $180 suitcase. Then she has the best of both worlds for a minor investment. They both will stay plugged into controller so all that is needed is to drag out the suitcase. Then in the dead of winter both can be set out at once when its really needed.

If space is an issue theres a 100w suitcase at solarblvd for $130

Mounted can mean many things.  

I can visualize a 4 wing nut mount and several other types of easily irremovable latch mounts.

We carry bicycles, kayaks, etc. and manage to put them on and them take off.

Not a Mission Impossible task.

This is a cheaper more powerful alternative to a $180 suitcase:


[video=youtube]

 

[Blanch]

Mounted can mean many things.  

I can visualize a 4 wing nut mount and several other types of easily irremovable latch mounts.

We carry bicycles, kayaks, etc. and manage to put them on and them take off.

Not a Mission Impossible task.

This is a cheaper more powerful alternative to a $180 suitcase:


[video=youtube]

I have a cheap $125 two stroke generator very similar to the one you show. After my expensive generator was stolen I went with a more affordable option. 1000 watts, it can run my microwave and charge my batteries when the sun just isn't enough. This past two months it was a life saver as the smoke from all the PNW fires made my solar set up unable to keep the batteries charged. I wouldn't consider traveling with out it.


Sent from my iPhone using Tapatalk

 

[66788]

I am attempting to run a cpap and a 40 liter compressor fridge off of 100 watts.  First attempt was a fail, but I am tweaking my system incrementally and increasing my education.

The Walmart 5 day bear resistant coolers have the best price point.

I ran a CPAP (Remstar Pro), powered roof vent (MaxxAir), LED interior lights, charge phone and tablet, and an ARB 47 liter compressor fridge on a single 120 watt Kyocera panel for two years.  I added an additional panel later, but found it wasn't necessary, as the Kyocera was doing a great job. I use a MorningStar Pro 30 charge controller and an AGM house battery.

The trick with using a  CPAP in a van is to not use the humidifier, as the heating element in that unit draws a lot of amps.  Just use the CPAP alone and the draw is negligible.  I find I don't like the warm moist air and can't sleep using it, so I run the bare machine.   I've done that for 10 years now.

For rainy weather, I carry a Honda 1000 watt generator, but seldom use it.

 

[duckwonder]

Is it possible to run a generator for 30 minutes in the morning and use a small coffee pot, figuring a use of power here but also charging the battery and helping out the solar? Is it a good idea to charge a power bank instead of individual electronics and then charge electronics from the power bank instead? How much I wonder could I use the fantastic fan (I love that thing)? If I bring a few CDs and DVDs and use an old school battery-op walkman for music (instead of my phone) and DVDs instead of streaming, might that help?

 

[frater secessus]

From the lead-acid battery bank's point of view, the best time to run the generator is in the morning when their state of charge is lowest. From the generator's point of view, the best way to use it efficiently is to use its full capacity. So coffee pot plus battery charging in the morning is a great idea.

As for charging devices vs. the bank: the bank always comes first. When the controller is out of Bulk mode you are, generally speaking, safe to start charging other devices.

I don't know about the three-speed models, but the multi-speed units from Fantastic and Maxxair both use very little power at the lowest settings. You could also use the thermostat (if present) to good effect; it would autorun the fan when needed.

 

[John61CT]

Is it possible to run a generator for 30 minutes in the morning and use a small coffee pot, figuring a use of power here but also charging the battery and helping out the solar? Is it a good idea to charge a power bank instead of individual electronics and then charge electronics from the power bank instead?

In the end, each day you have to restore 100% of what you used, plus 10-30%.

If you run down a lot of little batteries every day then pull power from the bank to recharge, the second number is higher, plus wearing out more batteries with finite lifetimes.

Plug as much as possible direct into the main House bank and keep their little batts full.

Run the genny with a big charger in the early morning into a high-CAR bank until its 75-85% full, then use the solar to get to 100% which should take at least 3-4 hours if the SC is holding Absorb properly.

Any smaller batts that need charging should start after you see Amps dropping in the later stages.

If you see you're getting to true 100% full early, then start reducing morning genny runtime, according to weather conditions. With a good SoC meter you'll soon get a feel for it.

 

[DLTooley]

I ran a CPAP (Remstar Pro), powered roof vent (MaxxAir), LED interior lights, charge phone and tablet, and an ARB 47 liter compressor fridge on a single 120 watt Kyocera panel for two years.  I added an additional panel later, but found it wasn't necessary, as the Kyocera was doing a great job.   I use a MorningStar Pro 30 charge controller and an AGM house battery.

The trick with using a  CPAP in a van is to not use the humidifier, as the heating element in that unit draws a lot of amps.  Just use the CPAP alone and the draw is negligible.  I find I don't like the warm moist air and can't sleep using it, so I run the bare machine.   I've done that for 10 years now.

For rainy weather, I carry a Honda 1000 watt generator, but seldom use it.

I've been using a non-humidified CPAP off of a Walmart Marine for several years.  I think the 'flex' option significantly reduces power from the maximum watts.

This is the controller I have: 

https://www.amazon.com/gp/product/B00AE3UEUE/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

 

[66788]

I've been using a non-humidified CPAP off of a Walmart Marine for several years.  I think the 'flex' option significantly reduces power from the maximum watts.

This is the controller I have: 

https://www.amazon.com/gp/product/B00AE3UEUE/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

That was my first charge controller many many years ago.   
Get rid of it.  
It is a shunt "on, off" device that should be replaced by a good quality PWM or MPPT controller.

MorningStar makes a good quality PWM charge controller series called the SunSaver.   A new SS10-12v will run about $40.00 to $50.00

https://www.amazon.com/SunSaver-Charge-Controller-12V-10A/dp/B002MQW3H8
https://www.solar-electric.com/ss-6.html

Outback makes a good MPPT charge controller for your 100 watt panel here:

https://www.amazon.com/Outback-Smar...r=8-5&keywords=outback+mppt+charge+controller

When I was using the controller you have, my solar system did not perform at all.   Quality components make all the difference in the world, and your Renogy 100 watt panel is good quality.   Change the charge controller.

 

[DLTooley]

Thanks!  The new Renogy PWM has 30 amps, an LCD display, and battery/temperature monitoring - found from your Amazon link.

https://www.amazon.com/Renogy-Adven...=1506441325&sr=1-1&keywords=renogy+advanturer

 

[jonsun]

you cant go wrong with the victron for small amps or the chinese MPPT for around $80-150. temp sense, bluetooth, rj-11 or whatever for your laptop, or the MT-50 remote.

HQST, solar epic, epever, etc
https://www.amazon.com/HQST-MPPT-So...ons&keywords=mppt+charge+controller+20a&psc=1
+
https://www.amazon.com/dp/B016RU8JUY/ref=psdc_2236627011_t2_B074GWFQC3

 

[duckwonder]

Thank you everyone. I can't find the solar controller for the solar panel I currently have, hopefully will locate by tomorrow and know more. Is there a chance it could be mounted on the chassis?