Solar performance #s

[Itinerant1]

I posted some of this on another board and thought it might interest some seeing there are a lot of solar system installs on rv using folks here. Here are some numbers from the past year. Habit from the past of record keeping info for performances and cost. A quick run down of dispersed camping, solar system and performance of system. If you keep records of your system and performance please post. It might help others on what they want with possible expectations.

Dispersed camping
2016 (4/16 - 12/31) 200 days
2017 (1/1 - 12/31) 365 days
Consecutive days dispersed camping as of January 8, 2017 starting 12/23/16 - 381 days, still going.

Using previous 2 years of rving (fulltiming) prior to solar install (4/13/16), RV park cost averaged to $25.00 a day.
443 days of dispersed camping needed for return on solar. System has paid for itself.

States AZ, UT, WY, ID, MT, ND, SD, NV
6,105 miles traveled with 5th wheel

Solar info...
Installed at Starlight Solar in Yuma, AZ last year in the spring.

*12v 500ah (400ah usable) lithium batteries (GBS LFP battery system) http://www.starlightsolar.com/elite-power-solutions-lfmp-battery/index.html
*8 CTI-160 watt monocrystalline solar panels (1,280 watts), 2 in series, 4 sets parallel (37 vmp). Panels lay flat on the roof.
*Combiner box to Magnum PT100 controller
*Magnum 3012 hybrid inverter (3000w).
There is a 7" display monitor and the ME-ARC 50 to read the performance of the system, individual cell voltages/ cell temps. A sub panel was added so everything in the 5th wheel except the water heater is running through the inverter.
Total weight for entire system 500#

This is what the system has harvested since the beginning of the year (2017) by month. Every morning I'll record previous day data from the Me-Arc.

Month ____ KWH_____ Ah to batteries
January___87.3______6,360
February__101.4_____7,410
March_____136.5_____9,950
April_____166.8_____12,210
May_______167.6_____12,260
June______164.2_____12,030
July______174.6_____12,770
August____152.1_____11,150
September_108.0_____7,920
October___90.0_____6,540
November _84.3______6,200
December _94.5______6,710
Total __1,527.3kwh___111,510ah
On/Work hours 4,214.4

*Harvest Total – Displays the total amount of energy in kilowatt hours (shown as KWH) delivered to the batteries.
*AH to Batt – Displays the total amp-hours (AH) delivered from the PT array to the DC system.
*On/Work Time – Displays the number of hours of active production by the PV array.

* Highest daily kwh haversted was on July 21st of 7.4 (740ah) in Idaho outside of Yellowstone National Park.

* Lowest daily kwh harvested was on September 15th of 0.2 (20ah) in North Dakota outside of Theodore Roosevelt National Park. Heavy overcast skies with rain.

In the past year the Honda EU2000i genterator has been used 7 times for 2 hours each time which charges at 100ah rate from the Magnum 3012 inverter/ charger into the battery bank and 3 times for 3 hours each when we ran the air conditioner before heading to higher elevation. Some of these run times where just to exercise the generator.

[Itinerant1]

For those interested. For not using voltage with LFP as a SoC here are examples from my system with 500ah GBS batteries/ EMS and a Magnum 3000 hybrid inverter. The system is 2 years of continual fulltime use and the past 460 days of boondocking with no hookups only the solar and a honda 2000 generator used for a hold over boost if needed on the third or fourth day of poor weather. The inverter is always on with a 2ah parasitic draw.
These are early morning readings before turning the coffee pot on (0630-0700) SoC and voltage from the Me-Arc display which only shows the voltage as xx.x vdc with 2a draw (inverter). 1%=5ah
32% 12.9
37% 13.0
41% 13.0
42% 13.0
54% 13.0
56% 13.0
58% 13.0
59% 13.0
63% 13.1
69% 13.1
74% 13.1
As can be seen there would be alot guessing used for SoC using voltage.

**13.33vdc is roughly resting voltage at 100%***

Now a couple using the actual display with readings from the EMS display which shows xx.xx vdc.
32% Inverter 12.9 2a, ems display 13.03vdc
74% Inverter 13.1 2a, ems display 13.26vdc

32% microwave/ inverting 12.5 150a after use the EMS display 13.03vdc
74% microwave/ inverting 12.9 150a after use the EMS display 13.17vdc

Example of the displays with 41a being drawn from the norcold fridge, tv charging laptop.

[Itinerant1]

pnichols wrote:

MEXICOWANDERER wrote:
I suggest looking up the word "adjunct"

99% of the places I used to camp had at least partial shading for a considerable percentage of the day.

On a beach just north of Puerto Vallarta around seven years ago I was invited to a campfire evening party where the air temperature at 8:00PM was around 55F

It was a big group. Some folks from British Columbia, others from Alberta and even one from Saskatoon. Friends were from Washington, Oregon, and Idaho. Around 20 people or so were sitting around the fire.

There was discord. All of them had solar panel charging. One fellow even clad his toy yanker trailer with panels.

The issue was too high of daytime temperatures inside the rig. Full sun was needed. And some folks had had enough. They were pulling out and heading for an RV park.

What is seldom discussed in discussions is the heat tolerance or vulnerability of people. Some it seemed get overheated when air temperature climbs to 75F. Many of these folks lived in British Columbia or the wet side of the Cascades in Washington and Oregon.

I can tolerate heat myself to a point. Humidity is a big factor. But I have seen days with no shade where inside rig temperatures climbed to 105F+ with 70% humidity. I'd like to meet the folks who are convinced those numbers are comfortable.

Aside from solar panels high in the mountains, I bailed out of my house when temperatures reached 98F at 6,780 feet. The whole tiny town was complaining. I traveled up up up to the top of Tioga Pass, 9945 feet, parked at 10,000 and climbed straight up. My NIST lab mercurty thermometer was registering 91F beside me in my shadow. I moved into the shade of a stunted sugarpine and it was a shock.

Down here, way way down here, temperatures seldom drop to the sixties. People tend to live around their rig, not in it during the day even parked in the shade. I know of no one who parks in the sun down here.

So with all due respect, claiming solar voltaics is "The Answer" without qualifying and without caveats can be misleading -- even deceptive.

The whole picture should be painted. To me the first priority of RV'ing is safety, followed by comfort.

Heat Prostration For Amp Hours may not be someone's idea of a good trip.

But kudos on your report.

David ... thanks for a great commentary! X2 here.

My take on what you are basically/partially saying is: You need lots of sun for RV solar harvesting ... but lots of sun is often incompatible with living in and around an RV in that sun without having to also have a generator along for air conditioning of that RV. Dealing with those two incompatibles is a paradox wrapped in an enigma wrapped in a conundrum wrapped in a quandary.

That's why we consider it essential to always have an RV generator along to power it's air conditioning - regardless of how many solar watts one might have on board. We refuse to have to move our RV drycamp (or go home) just because the sun is cause for it being too hot inside the RV - assuming that we're in a particular spot for some reason other than for chasing non-hot temperatures. One reason we have a self-contained RV is so us and the dog can be comfortable in places where we can't be comfortable in a tent, so a generator must be part of the complete RV equation.

Maybe our generator can be left at home when affordalbe solar panels are >75% efficient. :h

Well said.

[pnichols]

MEXICOWANDERER wrote:
I suggest looking up the word "adjunct"

99% of the places I used to camp had at least partial shading for a considerable percentage of the day.

On a beach just north of Puerto Vallarta around seven years ago I was invited to a campfire evening party where the air temperature at 8:00PM was around 55F

It was a big group. Some folks from British Columbia, others from Alberta and even one from Saskatoon. Friends were from Washington, Oregon, and Idaho. Around 20 people or so were sitting around the fire.

There was discord. All of them had solar panel charging. One fellow even clad his toy yanker trailer with panels.

The issue was too high of daytime temperatures inside the rig. Full sun was needed. And some folks had had enough. They were pulling out and heading for an RV park.

What is seldom discussed in discussions is the heat tolerance or vulnerability of people. Some it seemed get overheated when air temperature climbs to 75F. Many of these folks lived in British Columbia or the wet side of the Cascades in Washington and Oregon.

I can tolerate heat myself to a point. Humidity is a big factor. But I have seen days with no shade where inside rig temperatures climbed to 105F+ with 70% humidity. I'd like to meet the folks who are convinced those numbers are comfortable.

Aside from solar panels high in the mountains, I bailed out of my house when temperatures reached 98F at 6,780 feet. The whole tiny town was complaining. I traveled up up up to the top of Tioga Pass, 9945 feet, parked at 10,000 and climbed straight up. My NIST lab mercurty thermometer was registering 91F beside me in my shadow. I moved into the shade of a stunted sugarpine and it was a shock.

Down here, way way down here, temperatures seldom drop to the sixties. People tend to live around their rig, not in it during the day even parked in the shade. I know of no one who parks in the sun down here.

So with all due respect, claiming solar voltaics is "The Answer" without qualifying and without caveats can be misleading -- even deceptive.

The whole picture should be painted. To me the first priority of RV'ing is safety, followed by comfort.

Heat Prostration For Amp Hours may not be someone's idea of a good trip.

But kudos on your report.

David ... thanks for a great commentary! X2 here.

My take on what you are basically/partially saying is: You need lots of sun for RV solar harvesting ... but lots of sun is often incompatible with living in and around an RV in that sun without having to also have a generator along for air conditioning of that RV. Dealing with those two incompatibles is a paradox wrapped in an enigma wrapped in a conundrum wrapped in a quandary.

That's why we consider it essential to always have an RV generator along to power it's air conditioning - regardless of how many solar watts one might have on board. We refuse to have to move our RV drycamp (or go home) just because the sun is cause for it being too hot inside the RV - assuming that we're in a particular spot for some reason other than for chasing non-hot temperatures. One reason we have a self-contained RV is so us and the dog can be comfortable in places where we can't be comfortable in a tent, so a generator must be part of the complete RV equation.

Maybe our generator can be left at home when affordable solar panels are >75% efficient. :h

[Smitty77]

OP - Thanks for sharing our numbers... Enjoy!!!

Best to all,
Smitty

[Almot]

Chum lee wrote:

ALDI is a +-12,000 sq. ft. retail store with solar panels covering about a 30% of the roof area. On a good day in the summer I've seen the output as high as 25 Kw so winter sun and slight cloud cover takes a big hit on the solar output.

15-20 KW is what 30KW system in LA should be getting on an average day in December below 500ft. 3,000 KWH or more total monthly. The difference btw winter sun and summer sun in this area on flat install is 1.4-1.5 times - this includes clouds effect. Not 8 times.

Hard to tell why it was only 3KW under thin clouds on that particular day. Bad install, bad wiring, bad grid-tie interaction, bad LA smog, bad cleaning lady. I don't camp at high elevations, don't like it, "maybe" there are weather abnormalities in this location affecting the output that I don't know of.

[Almot]

Mex, Puerto Vallarta is not only hot but humid. I would probably want either shade or A/C under these circumstances.

Depends on your habits, too. Staying all day inside the trailer at 90 isn't smart. It's more comfortable in a hammock under palapa or near water. Huge mass of water and adjacent layer of air kept at constant 75 with some breeze, nice. Two hundred feet inshore it's an oven. Take a shower - yes, goosebumps instantly. Beautiful.

Up to 85 is fine in my books, and I am from BC. People who get overheated at 75 to the point that they need a fan or A/C - you gotta be kidding. But, if so, - they are not suited well for these adventures, and I don't think that Northern roots are the main reason. Probably have dietary issues and other restrictions too. Comfortable temperature zone shrinks when you get old - not old-er, but old, that's the sad truth. Remember South Park episode where Stan threatens the residents of Seniors Home to lower the thermostat down from 76 to 75.5? 🙂

[MEXICOWANDERER]

Hot Hot Hot

Ice
Milk
Banana
Sugar
Canned peaches
Blender

Liquify until sludgy. Pour into pre-frozen huge mug.

Slurp or spoon feed until teeth hurt and forehead feels like there is an arrow sticking out of it. Notice goose bumps. You'll feel so glad to warm um again.

Then go for a swim in the ocean. Relax under a palm frond roof beach restaurant. Have a shrimp or lobster cocktail. Dark almost frozen beer in a tall thick mug.

Wobble over to a shaded hammock. Fall into it. Let the afternoon trade winds tweak the twin coconut palms swaying in the afternoon trade winds.

[BFL13]

Good info! Not easy to relate to solar requirements for a "long-weekend warrior", but very interesting. Scenario is everything as usual. 🙂

On heat etc, I always note if it is too cold you can put on more clothes to keep warm; when it is too hot, after you are naked you can't take any more clothes off.

[Chum_lee]

Almot wrote:

Chum lee wrote:
about 2pm. They have +-30Kw of fixed solar panels on the roof. With a thin cloud layer at about 10,000 feet (sun visible through clouds) the LCD monitor screen showed the total instantaneous output to be 3kw. Not impressive at all!

3KW could be what their loads demanded?

Like I said, my system gets topped up before noon, if there is any sun. At that point batteries are very close to full (more in AGM, less in flooded), and controller output drops to a trickle, except for what loads demand.

Here is estimated AC output for flat 1.1 KW (for example) in El Centro CA. In line with what I and others observed. You can get estimates for most US cities, based on long-term statistics: http://pvwatts.nrel.gov/.

Month kWH

January 150
February 136
March 172
April 178
May 174
June 161
July 158
August 165
September 159
October 151
November 142
December 146

According to the store manager and the store monitoring system, the system feeds any excess power generated back to Southern California Edison (which is credited against their current usage) as do most grid tied solar systems in California. ALDI is a +-12,000 sq. ft. retail store with solar panels covering about a 30% of the roof area. On a good day in the summer I've seen the output as high as 25 Kw so winter sun and slight cloud cover takes a big hit on the solar output.

Chum lee

[Itinerant1]

Other than AZ before heading north where it was mid 90s I can honestly say the inside of the rig was at 90 once. Most of the time 80-85 nothing that a fan can't handle. Inside battery compartment highest temp was 85, average temp 75-80 during the day. Good thing for a dry heat. 😉 There are wheels under these rv's for moving to elevation. Proper positioning helps with afternoon shade from trees. Having to sit in an open field isn't a must for gathering a good charge.Plus only using 150+/-ah isn't much to put back in the battery bank a few hours in the summer.

Should of added evening temps 50-65 nice sleeping.

[MEXICOWANDERER]

I suggest looking up the word "adjunct"

99% of the places I used to camp had at least partial shading for a considerable percentage of the day.

On a beach just north of Puerto Vallarta around seven years ago I was invited to a campfire evening party where the air temperature at 8:00PM was around 55F

It was a big group. Some folks from British Columbia, others from Alberta and even one from Saskatoon. Friends were from Washington, Oregon, and Idaho. Around 20 people or so were sitting around the fire.

There was discord. All of them had solar panel charging. One fellow even clad his toy yanker trailer with panels.

The issue was too high of daytime temperatures inside the rig. Full sun was needed. And some folks had had enough. They were pulling out and heading for an RV park.

What is seldom discussed in discussions is the heat tolerance or vulnerability of people. Some it seemed get overheated when air temperature climbs to 75F. Many of these folks lived in British Columbia or the wet side of the Cascades in Washington and Oregon.

I can tolerate heat myself to a point. Humidity is a big factor. But I have seen days with no shade where inside rig temperatures climbed to 105F+ with 70% humidity. I'd like to meet the folks who are convinced those numbers are comfortable.

Aside from solar panels high in the mountains, I bailed out of my house when temperatures reached 98F at 6,780 feet. The whole tiny town was complaining. I traveled up up up to the top of Tioga Pass, 9945 feet, parked at 10,000 and climbed straight up. My NIST lab mercurty thermometer was registering 91F beside me in my shadow. I moved into the shade of a stunted sugarpine and it was a shock.

Down here, way way down here, temperatures seldom drop to the sixties. People tend to live around their rig, not in it during the day even parked in the shade. I know of no one who parks in the sun down here.

So with all due respect, claiming solar voltaics is "The Answer" without qualifying and without caveats can be misleading -- even deceptive.

The whole picture should be painted. To me the first priority of RV'ing is safety, followed by comfort.

Heat Prostration For Amp Hours may not be someone's idea of a good trip.

But kudos on your report.

[Almot]

Chum lee wrote:
about 2pm. They have +-30Kw of fixed solar panels on the roof. With a thin cloud layer at about 10,000 feet (sun visible through clouds) the LCD monitor screen showed the total instantaneous output to be 3kw. Not impressive at all!

3KW could be what their loads demanded?

Like I said, my system gets topped up before noon, if there is any sun. At that point batteries are very close to full (more in AGM, less in flooded), and controller output drops to a trickle, except for what loads demand.

Here is estimated AC output for flat 1.1 KW (for example) in El Centro CA. In line with what I and others observed. You can get estimates for most US cities, based on long-term statistics: http://pvwatts.nrel.gov/.

Month kWH

January 150
February 136
March 172
April 178
May 174
June 161
July 158
August 165
September 159
October 151
November 142
December 146

[pianotuna]

Itinerant1,

Thanks for the great report!

[Chum_lee]

Last Saturday (1-6-2018) I was in the local ALDI store in Los Angeles at about 2pm. They have +-30Kw of fixed solar panels on the roof. With a thin cloud layer at about 10,000 feet (sun visible through clouds) the LCD monitor screen showed the total instantaneous output to be 3kw. Not impressive at all! I hope the state of California gave them a real good tax incentive to install the system because that day it surely wasn't paying for itself. (the CA residents were) That said, I am a big fan of solar power.

Chum lee