RV Energy Audit Results...Seriously?!?!?!

[LivingTheDream]

Hello everyone,

First time posting, first time RVer, first time solar, so be gentle.

• So we live in Arizona (great sun), but we will be traveling a lot, mainly CO, WY, MT, MN, CA, and everything in between.
• I have a 44' Toy Hauler Fifth Wheel pulled behind an F350 dually.
• We have three A/C units, which I hope to not have to run, and if I do, then I'm doing something wrong.
• There is a generator that I'm perfectly fine running to help my systems short falls. Obviously, less is better.
• Residential fridge on 110v with an inverter that kicks off at 12v, which sucks and is causing food to spoil.
• Water Heater is electric and/or gas.
• Try to cook with the BBQ or Pellet Grill as much as possible.
• Both have laptops that only need charging once a day. Wife uses a large monitor on 110v.

I just did an energy audit and the results were quite shocking.

Inverter

I realize that the inverter needed will only need to be big enough to handle those items that I would run at the same time, so a 3k should be sufficient. Let me know if I'm wrong.​

Battery Sizing

I have 8 cells of the Lishen 272ah on order with Michael Caro. I'm looking at wiring these for a 24v system. The audit is saying 430ah and 10,300wh. Yikes! Maybe I should've ordered 16 cells. Can I mix and match Lithium Batteries, or should I just put in another order and pray China has their act together and it won't take another 3-4 months? Or am I off in my expectations?​

Solar Array

I have a big rig, but I cannot get 2472w of solar on my roof. Again, what am I missing? I thought I was going to be good at 800w of solar, wow was I off.​

​

Alright, if I missed something, just ask. I look forward to hearing what you pros have to say!

Sincerely,
Brian

 

[carbon60]

I think heating water is a huge one in there, as well as 15 minutes of blow drying at full blast?

 

[LivingTheDream]

I think heating water is a huge one in there, as well as 15 minutes of blow drying at full blast?

The water takes about 30 minutes to heat for a shower, I could supplement this with either gas, or the generator I suppose. Also, wife has long Latina hair, so yes, it takes a bit too dry. This isn't every day though and it wouldn't be at full blast. So that saves us a bit. I'm still over 400ah of battery and 2330w of solar.

 

[carbon60]

I'm struggling a little understanding those spreadsheets, sorry. Do you have them as a Google Sheet or similar?

 

[12VoltInstalls]

Run hot water on propane.

Fridge shouldn’t be terrible to run on solar. Maybe you need to buy a new smaller one? If it’s an emulsion fridge they use 4 or 5 times the electric power a standard small compressor fridge does

1500W hair dryer is 400Wh by itself...

I didn’t study your paperwork but it does seem like a lot of consumption.

 

[LivingTheDream]

I'm struggling a little understanding those spreadsheets, sorry. Do you have them as a Google Sheet or similar?

I have it as a Numbers file for Mac. However, I can export it to Excel, CSV, or TSV if you'd like.

 

[LivingTheDream]

Run hot water on propane.

Fridge shouldn’t be terrible to run on solar. Maybe you need to buy a new smaller one? If it’s an emulsion fridge they use 4 or 5 times the electric power a standard small compressor fridge does

1500W hair dryer is 400Wh by itself...

I didn’t study your paperwork but it does seem like a lot of consumption.

Thank you 12volt. Yes, it is a big fridge at 18cuft. The brand is Hisense and I'm not sure how they compare to other's of similar size. I'd have a hard time convincing the wife to get a smaller one considering we're full time. That might just be one of those sacrifices I have to make and bight the bullet. I'll see if I can find something more efficient of similar size though.

 

[grizzzman]

Unless you want to deploy a ground array or perhaps a large headache rack on the dually with panels, you are limited by your roof space. I suggest that you fill the roof with panels and and related equipment to support it. Then adjust your use as needed. (and you do have a generator)

 

[LivingTheDream]

Unless you want to deploy a ground array or perhaps a large headache rack on the dually with panels, you are limited by your roof space. I suggest that you fill the roof with panels and and related equipment to support it. Then adjust your use as needed. (and you do have a generator)

Thank you grizzzman, that's kinda what I was thinking. Put as much solar on the roof as I'm willing to do so, then get a larger battery bank so when I do have to run the generator, I have more storage for the energy. Then maybe I'll only have to run it for 30-60 minutes once a day.

 

[Will Prowse]

Energy audits for PV array sizing considerations are usually of little importance in my experience. Fill the roof with as many panels as you can. Then size the battery to the size of your wallet.

Update: page refreshed and @grizzzman said the same thing. Oops

 

[12VoltInstalls]

EDIT- I’m late to the party. But I’ll leave this anyways.

See if you can put two or three rows of those squarish-sized 250W panels on the roof. 24V. Then see how many will fit. Depending on obstructions my head says you can do at least 3kW on there. That’s A LOT. Being flat you’ll lose say 15 or 20% of capacity but they’ll work.

 

[LivingTheDream]

Energy audits for PV array sizing considerations are usually of little importance in my experience. Fill the roof with as many panels as you can. Then size the battery to the size of your wallet.

Update: page refreshed and @grizzzman said the same thing. Oops

Thanks Will. I'm really enjoying your videos as I try to learn this stuff!

 

[LivingTheDream]

EDIT- I’m late to the party. But I’ll leave this anyways.

See if you can put two or three rows of those squarish-sized 250W panels on the roof. 24V. Then see how many will fit. Depending on obstructions my head says you can do at least 3kW on there. That’s A LOT. Being flat you’ll lose say 15 or 20% of capacity but they’ll work.

Which panels are you referencing? I haven't seen any square 250W panels. I just watched the shoot out that @Will Prowse did with Renogy, NewPowa, HQST, and another that I can't remember. Being in AZ, I was thinking of getting some SanTanSolar T-series panels. However, I'm open to suggestions.

 

[HRTKD]

To optimize the roof real estate, create a CAD drawing of the roof (to scale). Then create templates of solar panels and fit them on the drawing. That's how I arrived at my layout.

I started with the thought that I was going to put up four 200 watt panels. Reality smacked me upside the head and there was no way to arrange those four panels on my toy hauler's roof. I switched to two 320 watt panels instead. I had to remove the trailer roof rack to do it.

To supplement the roof panels, I also have 640 watts of ground deployed portable panels. You have a toy hauler, so you should have room to store panels for ground deployment.

This database of solar panels can be sorted/search based on size. It's a good way to find the panels you need once you know what will fit. A layout that uses panels of the same size is easier to deal with than a layout with panels of differing sizes.

PV Module List - Full Data

www.energy.ca.gov

 

[LivingTheDream]

To optimize the roof real estate, create a CAD drawing of the roof (to scale). Then create templates of solar panels and fit them on the drawing. That's how I arrived at my layout.

I started with the thought that I was going to put up four 200 watt panels. Reality smacked me upside the head and there was no way to arrange those four panels on my toy hauler's roof. I switched to two 320 watt panels instead. I had to remove the trailer roof rack to do it.

To supplement the roof panels, I also have 640 watts of ground deployed portable panels. You have a toy hauler, so you should have room to store panels for ground deployment.

This database of solar panels can be sorted/search based on size. It's a good way to find the panels you need once you know what will fit. A layout that uses panels of the same size is easier to deal with than a layout with panels of differing sizes.

PV Module List - Full Data

www.energy.ca.gov

Thank you for the suggestion. Yes, I should have room to do a ground array as well. I've thought about getting 3-4 of the larger 450w panels for the ground and avoid the roof entirely. I'm not concerned about charging while on the move. However, I'm just concerned with leaving the panels out while we run to town for supplies and such. It's a little less secure and may be tempting for someone.

 

[BlueFox]

Have you actually measured these power consumption figures or are you just reading labels?

I ask because you have a monitor at 114W which is crazy unless it's either very large, or the brightness is at 100% which is generally never the case. Is the 8 hours a day a typo since both laptops only have 2 hours a day?

A soundbar at 90W seems crazy too, as does a Mofi router at 96W. Both of those I would expect to be in the area of 10-20W while in use.

Going around with a watt meter and plugging things in would give you more accurate results, you may need a lot less energy than you've calculated here.

 

[HRTKD]

Thank you for the suggestion. Yes, I should have room to do a ground array as well. I've thought about getting 3-4 of the larger 450w panels for the ground and avoid the roof entirely. I'm not concerned about charging while on the move. However, I'm just concerned with leaving the panels out while we run to town for supplies and such. It's a little less secure and may be tempting for someone.

My 320 watt panels are no fun to store and move. I can't imagine a 450 watt panel. I did create a frame for my panels out of aluminum so I could tilt them and secure them to the ground. That added weight for sure.

In retrospect, I should have bought three or four 200 watt panels for the ground deployment. Easier to store and move.

 

[LivingTheDream]

Have you actually measured these power consumption figures or are you just reading labels?

I ask because you have a monitor at 114W which is crazy unless it's either very large, or the brightness is at 100% which is generally never the case. Is the 8 hours a day a typo since both laptops only have 2 hours a day?

A soundbar at 90W seems crazy too, as does a Mofi router at 96W. Both of those I would expect to be in the area of 10-20W while in use.

Hello @BlueFox, I am just reading labels.

• The monitor is a 34" Curved LG. So yeah, it's big. I have the laptops at 2hrs/day since they can run off their batteries. Being Apple, they last most of the day on a single charge. There could be some savings on the brightness levels though.
• The sounder kinda floored me as well. The wife likes to always have music playing in the background, so I may invest in a rechargeable JBL or Bose for her.
• The Mofi also seemed crazy high to me. I was thinking I could just leave that on 24/7, but not with what the label said.

Maybe I should invest in one of those devices that measures the usage. Do you know what they are called by chance? I'll look on Amazon.

 

[John Frum]

Here is an alternate way to get the size and scale of the system.

Assuming you have a 30 amp shore power plug on your trailer...
Create the equivalant of a 30 amp shore power pedestal off of your house panel
Plug your trailer into the the shore power pedestal
Monitor the entire trailer with one of these https://sense.com/product
Camp in your driveway to get a very good estimate of your real world requirements.
That will give you a really good idea of your peak usage in watts and your daily usage is watt hours.
Its what I would do.

 

[LivingTheDream]

Here is an alternate way to get the size and scale of the system.

Assuming you have a 30 amp shore power plug on your trailer...
Create the equivalant of a 30 amp shore power pedestal off of your house panel
Plug your trailer into the the shore power pedestal
Monitor the entire trailer with one of these https://sense.com/product
Camp in your driveway to get a very good estimate of your real world requirements.
That will give you a really good idea of your peak usage in watts and your daily usage is watt hours.
Its what I would do.

Only problem @smoothJoey, we sold our house and live off grid 100%. Not really a problem, but you get what I mean. I just ordered a meter for individual items. In the mean time, I'll research solar panels and layouts.