Power Required, Truck/Car camping

[Dave in AZ]

To determine what size powerstation or 2nd battery system you need for your camping or overlanding, the first thing required is to do an "energy audit" to figure out daily use, for both peak dc watts, 120Vac watts, and total Watt-hrs used for battery sizing.

How you will recharge will determine final battery size, how much extra battery Watt-hrs you will need:
--No recharge, battery must cover
all days of trip.
--Alternator recharge, ~500W times hours of driving, so 1500Wh in 3hrs
--Solar, you need 2-3days power to account for poor solar days, more if in cloudy areas. Expect 5hrs max per day, 10-60% rated Watts if flat, 40-90% rated if angled. Depending on season and lattitude and tilt.

Energy Audit
Tier 1 Minimal power:
small battery powered headlights
1. LED lights , sparse and dim
20W, 6 hr, 120Wh
2.Fan, none or Maxxair setting 2 low
10W, 10 hr, 100Wh
3. Phones, small recharge stuff
25W, 4 hr, 100Wh
No dc refrigerator, heater, dc blanket, camp lights, water pump, or 120Vac
Totals:
12Vdc: 55W = 5A
120Vac: 0W
Battery 320 Watt-hrs or 25Ah@ 12.8V

Tier 2 Basic, dc only
small battery powered headlights
1. LED lights , well lit camper
75W, 5 hr, 375Wh
2.Fan, Maxxair setting 6 med
20W, 10 hr, 200Wh
3. Phones, small recharge stuff
25W, 4 hr, 100Wh
4. dc refrigerator 30L-75L
35W to 55W, 24hr, 400-800Wh
5. heater, diesel
120W startup, 20-40W run, 10hr, 210-410Wh
6. 12 dc blanket
30-65W, 9hr, 270-585Wh
7. Extra camp lights, led string etc
20W, 13hr, 260Wh
8. water pump?
Totals:
12.8Vdc 380W max = 29.7A
120Vac: 0W
Battery 1815 to 2715 Watt-hrs or 142 to 212 Ah@ 12.8V

Tier 3 dc and 120Vac cooking
All tier 2 totals PLUS this 120Vac:
1. Electric kettle, coffee/tea
1500W, 50Wh per 500ml i.e. travel mug, 4x mugs a day is 200Wh
2. Induction burner, reheat 500ml stew or meal
1800W max, 66Wh, 3x meals is 200Wh
Totals:
12.8Vdc 380W max = 29.7A
120Vac: 1800W max
Battery dc 1815 to 2715 Watt-hrs or 142 to 212 Ah@ 12.8V
Battery ac 400-600 Wh plus 100 for inverter, is 500-700Wh
Grand total battery 2300-3400 Wh
Or 180-265 Ah @ 12.8V
-------------
Analysis:
These are ONE DAY POWER! Multiply by days needed for total battery depending on your charging method!
Tier 1, any small 500Wh powerstation
Tier 2, 30A 12V dc outlet, 2000-3000Wh battery (can be station plus expansion battery or LFP)
Tier 3, 30A 12V dc outlet, 1800W min inverter,
2300-3400Wh battery (can be station plus expansion battery or LFP. For example, I use 1536Wh powerstation plus either a 3072Wh expansion battery or a 1280Wh LFP)


Power testing videos:
These all work, just disabled embedded here, click "watch on youtube" and also lots of written info on video descriptions!
Electric kettle vs induction, coffee

Reheat 1 meal stew, induction:

Cook Elec breakfast for 2 (coffee, oatmeal, bacon, eggs, 350Wh

Winter vs. Summer Solar, camping

 

[NOPEC]

To determine what size powerstation or 2nd battery system you need for your camping or overlanding, the first thing required is to do an "energy audit" to figure out daily use, for both peak dc watts, 120Vac watts, and total Watt-hrs used for battery sizing.

How you will recharge will determine final battery size, how much extra battery Watt-hrs you will need:
--No recharge, battery must cover
all days of trip.
--Alternator recharge, ~500W times hours of driving, so 1500Wh in 3hrs
--Solar, you need 2-3days power to account for poor solar days, more if in cloudy areas. Expect 5hrs max per day, 10-30% rated Watts if flat, 40-80% rated if angled. Depending on season.

Energy Audit
Tier 1 Minimal power:
small battery powered headlights
1. LED lights , sparse and dim
20W, 6 hr, 120Wh
2.Fan, none or Maxxair setting 2 low
10W, 10 hr, 100Wh
3. Phones, small recharge stuff
25W, 4 hr, 100Wh
No dc refrigerator, heater, dc blanket, camp lights, water pump, or 120Vac
Totals:
12Vdc: 55W = 5A
120Vac: 0W
Battery 320 Watt-hrs or 25Ah@ 12.8V

Tier 2 Basic, dc only
small battery powered headlights
1. LED lights , well lit camper
75W, 5 hr, 375Wh
2.Fan, Maxxair setting 6 med
20W, 10 hr, 200Wh
3. Phones, small recharge stuff
25W, 4 hr, 100Wh
4. dc refrigerator 30L-75L
35W to 55W, 24hr, 400-800Wh
5. heater, diesel
120W startup, 20-40W run, 10hr, 210-410Wh
6. 12 dc blanket
30-65W, 9hr, 270-585Wh
7. Extra camp lights, led string etc
20W, 13hr, 260Wh
8. water pump?
Totals:
12.8Vdc 380W max = 29.7A
120Vac: 0W
Battery 1815 to 2715 Watt-hrs or 142 to 212 Ah@ 12.8V

Tier 3 dc and 120Vac cooking
All tier 2 totals PLUS this 120Vac:
1. Electric kettle, coffee/tea
1500W, 50Wh per 500ml i.e. travel mug, 4x mugs a day is 200Wh
2. Induction burner, reheat 500ml stew or meal
1800W max, 66Wh, 3x meals is 200Wh
Totals:
12.8Vdc 380W max = 29.7A
120Vac: 1800W max
Battery dc 1815 to 2715 Watt-hrs or 142 to 212 Ah@ 12.8V
Battery ac 400-600 Wh plus 100 for inverter, is 500-700Wh
Grand total battery 2300-3400 Wh
Or 180-265 Ah @ 12.8V
-------------
Analysis:
These are ONE DAY POWER! Multiply by days needed for total battery depending on your charging method!
Tier 1, any small 500Wh powerstation
Tier 2, 30A 12V dc outlet, 2000-3000Wh battery (can be station plus expansion battery or LFP)
Tier 3, 30A 12V dc outlet, 1800W min inverter,
2300-3400Wh battery (can be station plus expansion battery or LFP. For example, I use 1536Wh powerstation plus either a 3072Wh expansion battery or a 1280Wh LFP)


Power testing videos:
These all work, just disabled embedded here, click "watch on youtube" and also lots of written info on video descriptions!
Electric kettle vs induction, coffee

Reheat 1 meal stew, induction:

Cook Elec breakfast for 2 (coffee, oatmeal, bacon, eggs, 350Wh

Dave thanks for taking the time to post this which is very helpful for electrical luddites like me. This kind of stuff here on EP is really gold...

 

[MR E30]

Dave,

Thanks for starting a thread like this.

I will share my experiences with my battery setups over the past 16 months. Not as many detailed numbers as you, but it should still be valuable.

For background: (2) full-time workers living in a DCLB Tacoma. Solar is our primary energy source, and has supplied ~97% of all of our energy since we set out. Our desire was/is as much solar power as possible. We are stationary folk, we do not drive long distances or long hours day after day, or even week after week.

Our use involves (items added over time): Charging (2) laptops (1 requires being plugged in all day) (3ah each), a 12v 47l ARB fridge set to 37 degrees F (1ah), diesel heater (2ah), 1800w induction cooktop (varies), Starlink powered via SL 120v AC Router (3.5ah), 3.5 gpm water pump (inconsequential), various USB charge ports, and LED lights.

Additional info:
- LED Interior Lights - We run these in the wintertime for an average of 4 hours per day it seems. We are early to bed and late to rise when it is dark and cold out. in the summer we use the interior LED lights for maybe a single hour each day. We stay up a bit later, but it is much easier to keep the windows open to let the fading sunlight into the camper as evening sets. We awake shortly after sunrise.
- Water pump - We have a 3.5gpm Shurflo in the truck, and we only use about 3 gallons of water per day. The pump doesn't actually dispense at 3.5gpm once the plumbing and filter are affixed, it flows around 1.75 gpm now, so the pump only runs for ~2 minutes per day. Its energy use is inconsequential really.
- Diesel heater - As Dave said, it needs a lot of amps (10a) during startup, but that process only lasts ~10 minutes or so. After that it drops down to 2-3ah. In the winter we run this for anywhere from 4-8 hours per day, depending on the temperature (obviously haha) and the cloud cover. We rarely run it throughout the entire night, and the average seems to be firing it up around 3 am to remove the chill from the air primarily, our bodies are still warm enough under our covers, but the exposed face and head gets annoyed by the cold air.
- Starlink - For us it is a 100% constant drain (at 3.5ah on 120VAC), though it certainly does not have to be. The bootup process for it (I can only speak to Gen 2, Gen 3 is a lot more 'mobile' friendly it appears) only takes 7 minutes or so, with a more stable and faster connection begin attained after 15-20 minutes most times. So you could certainly use it once or twice a day to check in with the world at the cost of just a smidge of electricity. I ran our setup on 12VDC initially (until the dish itself fried, internet is massive priority for wife's work, so went back to AC power for reliability reasons only) and it only pulled ~2.5ah, effectively saving ~24ah per day. The 12VDC products to power the dish have grown in availability over the last year, so I may look back into powering the Gen 2 dish via DC power once again, as after we stop working having a glitch in the internet won't be as big of a deal.
- ARB 47l Fridge - Set at 37F the fridge runs roughly 15 minutes every hour. At 4ah while running, that gives us an average of 1ah all day long. However, when we meal prep and load the fridge with recently cooked/heated food (we always try to let nature cool it down before putting it into the fridge, but in the summer this doesn't work out too well), the fridge can consume a lot more energy, along the lines of 3ah for 5-8 hours straight. Most people won't do this, I assume, but it is good to know.
- 1800w Induction Cooktop - I don't have enough use with this device yet to fully speak to its impact on the system, but I would guesstimate that on non-meal prep days (which happen to be stationary days) we use ~600wh each day. This mainly includes boiling water for morning tea, and warming (1) meal, our other meal is usually eaten cold. I need more time to determine what meal prep day energy usage is, though this occurs over the weekend, when we normally drive a bit.

Setup 1: Initial setup (was not expecting full-time energy use when originally designing system), used for late summer and fall of 2023

- 100ah LifePO4 and 200w solar on wedge roof
- Was running a 1000w Renogy inverter (went through two of them, both broke, would not recommend) for AC devices
- SL could only be run when it was needed
- No concerns running LED lights
- No concerns running water pump
- No concerns charging phones/tablet
- Fridge was always on, and draws ~1ah on average
- 12v electric blanket used sparingly at night
- No diesel heater or induction cooktop at this time
- Would require idling the truck every two days for 1 hr. during the 4 day work week. Truck uses .33 gph of fuel at idle, and delivered 50a each hour via Renogy 50a DCDCMPPT Charge Controller
- Battery down to as low as ~25% first thing in the morning, all devices, except for fridge, powered off at night. Depended on how long SL had to stay on after dark to finish work.
- Setup could not handle any cloudy days.
- A lot of 'range anxiety' with this setup.

My takeaways from Setup 1: This setup can be very useful for most, and supply you with all that you need, especially if your travel involves a lot of driving (i.e. daily), or if you have a very low energy demand. During our three day weekends (no laptops and short term SL use) we had no issues, battery up to 100% early in the day, etc. This setup simply did not work during the work week, and I did not want to have to worry about how much charge the battery had throughout the day.

Setup 2: Upgraded setup, used for most all of 2024

- 200ah LifePO4 and 400w solar on wedge roof.
- Upgraded to 2000w Sunthysis inverter.
- SL powered on 24/7 - it uses ~3.5 amps per hour
- Small devices caused no concern
- Fridge still at 37F
- No more electric blanket
- 12v diesel heater used in the early morning hours, sometimes ~8 hours per day
- Still no induction cooktop at this time
- Batteries down to ~80% overall charge each morning. Marked improvement over Setup 1 due to the additional 200w of solar on the wedge roof. In spring batteries hit full at ~1 pm. in summer batteries completely full as early as 11 am.
- Setup could handle 2-2.5 fully cloudy days
- Sparing use of truck engine at idle to charge batteries (once per month I'd say). If I knew we had driving to do I would allow the batteries to drain down to ~30% or so at night, but I would not do this if I knew we had another day or two of work before driving somewhere.
- Very little 'range anxiety' with this setup. Not having to power down SL at night was a huge bonus.

My takeaway from Setup 2: This setup can handle quite a lot of pickup truck campers lifestyles. I can easily charge any number of USB devices, very rarely did I worry about overall system charge level, it was really nice. This certainly is not enough for a larger vehicle, as AC for example would toast this system very quickly, but the way we used it it was great.

Setup 3: More Upgraded setup, Fall 2024, though still in process of understanding system

- 300ah of house batteries and 135ah of backup battery, still 400w solar on wedge roof (max that will fit).
- All the same as before with inclusion of 1800w induction cooktop.
- Absolutely no energy concerns whatsoever.
- System at ~90% charge each morning.
- Setup could likely go 5 days without any solar input, but even on fully cloudy days I will still grab ~40ah over the course of the day.
- Truck engine is no longer used as generator to recharge system, even after a full workweek of cloudy days (~55ah each day)

My takeaway from Setup 3: This is likely overkill, but I love not having to worry about my electrical system at all. I will go all week without checking charge levels once. I have had issues with old LifePO4 batteries, and with my intended adventuring style, I want some redundancy, hence the 300ah (if a Renogy battery BMS goes bad, the CC will not charge it or pull energy from it, basically deleting it from the system) and backup 135ah. At this point in time the induction cooktop has not been a problem, though the wife and I aren't massive cooktop users.

 

[Dave in AZ]

@MR E30
Michael, Fantastic post, super valuable info, thanks so much!

To any folks reading, you can see that Michael is technical and detail oriented, his posts are always chock full of useful info! He has a great thread, that I have really enjoyed reading, detailing some of his and Stacy's life full-timing it in a Tacoma with an Alu-Cab. I highly recommend, great pictures too! Here is the link:

Another Around the World Tacoma

We now live in our Tacoma Departed: September 1st, 2023 @ 4:15 PM at 22,734 miles ig: stacyandmike_plus2 The Tacoma, as of September 2024: [img]HSWOR...

www.tacomaworld.com