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Mike,
Seeing your comments on the truma furnace and induction cook top, how impractical would it be to have an all electric rig? (Without a generator) Granted you would need solar, inverter, 2-way frig, and wouldn’t be cheap, but I haven’t heard of anyone attempt it, although I’m aware some class B units go without propane.All electric rigs present an obvious problem in terms of power so even when possible they present considerable compromise in terms of practicality for how they can be used. Solar is nice, I have it on one of our rigs, but the sun doesn’t always shine.
I still remember the advice a close friend who was a solar manufacturer and avid RVer used to give when we did conferences together. First you buy the generator, then you buy the solar.
As with all things RV, there is never a prefect answer. My two cents.
Steve and Andra
2012 F350 6.2 gasser SRW LB
Fab Fours front and rear in case we run into a rhino
2019 Northstar Laredo SCElectric rigs are more common that many think. EarthRoamers and GXV rigs are all electric. Neither run on propane nor have a generator. For a standard slide-in truck camper to have the same capability, it would require at least four group-27 batteries and a minimum of 400 watts of solar. Most campers don’t have the room for that many batteries, which is one reason why flatbed campers are so popular (flatbed here can mean either a true flatbed camper or a standard slide-in truck camper mounted on a flatbed with storage boxes like those made by SherpTek). Flatbed campers have the room for more batteries, more water, and other goodies sought after by overlanders and those who full-time in their campers.
They are also available in other types of RVs, but having owned rigs with large inverters they do pose enough limitations so they have never really become popular. What’s the DC amp draw for an electric hot water heater in an all electric rig?
Steve and Andra
2012 F350 6.2 gasser SRW LB
Fab Fours front and rear in case we run into a rhino
2019 Northstar Laredo SCI am on my way to modifying my Lance 1130 to all electric. POWER SYSTEM: I am a couple days from building the battery which will be a tray to fit under the camper. It essentially is a riser platform, the footprint of the camper with a little extra ‘spread’ just inside the back of the bed. The tray will hold 36-64wh LiMgO2 battery packs from Nissan Leaf. The tray is exactly 2″ high. The area at the rear sides of the camper will be will have a ‘saddlebag’ on each side (attached to the riser) with 6 more battery packs on each side (48 packs total). This constitutes the whole Leaf battery. The batteries weigh 400lbs and the riser about 120. Loosing the Gp 31 AGM will gain back 110lbs. The battery will be configured in 4S12P, operate from 24V-32V and have 24kwh total capacity with just under 20kwh usable. The Electrodacus SB120 ‘Solar BMS’ which manages the battery and power in/out will have one input dedicated to solar on the roof that I expect to be around 600-800W. The other will be input from the 12V/250A vehicle alternator through DC-DC converters to bring it to 36V@75A (~2.7kw) to charge when we are moving. The DC battery will feed a Samlex 24V/120V/3000w inverter. I will remove the propane range/oven and repair the counter. I plan to use 2 portable induction units (not built in) so I can cook inside or out. I’m modifying the water heater with a 1250w/120V heating element controlled by an industrial PID control. The AC has heat strips but most space heating will be provided by a diesel-powered air heater (5kw) from the F350 diesel tank. Taking out the 2-7gal propane, furnace, and range should get me back ~200 lbs (dry). No specific plans yet on replacing the fridge freezer with a compressor unit but that is on the horizon.
Addendum: 1) Quite by accident, I purchased by 2015 leaf battery pack on CL for $300 with penetrating body damage to the steel outer container. This was a miracle I don’t expect to repeat. I expected to find damage to the batteries but only 2 packs and minor ‘injuries’. 2) The battery pack weighs (35 packs x 8.3lbs + 98 lbs for the frame + wiring and BMS) just under 400 lbs. 3) I have the system completed enough to test. It powers a (change) Samlex EVO-4024 (4kw @ 24v) inverter charger (110A charge at 28V). Our weather in SoCal is currently hovering around the 100 degree or more mark and the Dometic Penguin AC runs about 50% duty cycle. This alone can operate for over 16 hours on a charge.
I am on my way to modifying my Lance 1130 to all electric. POWER SYSTEM: I am a couple days from building the battery which will be a tray to fit under the camper. It essentially is a riser platform, the footprint of the camper with a little extra ‘spread’ just inside the back of the bed. The tray will hold 36-64wh LiMgO2 battery packs from Nissan Leaf. The tray is exactly 2″ high. The area at the rear sides of the camper will be will have a ‘saddlebag’ on each side (attached to the riser) with 6 more battery packs on each side (48 packs total). This constitutes the whole Leaf battery. The batteries weigh 400lbs and the riser about 120. Loosing the Gp 31 AGM will gain back 110lbs. The battery will be configured in 4S12P, operate from 24V-32V and have 24kwh total capacity with just under 20kwh usable. The Electrodacus SB120 ‘Solar BMS’ which manages the battery and power in/out will have one input dedicated to solar on the roof that I expect to be around 600-800W. The other will be input from the 12V/250A vehicle alternator through DC-DC converters to bring it to 36V@75A (~2.7kw) to charge when we are moving. The DC battery will feed a Samlex 24V/120V/3000w inverter. I will remove the propane range/oven and repair the counter. I plan to use 2 portable induction units (not built in) so I can cook inside or out. I’m modifying the water heater with a 1250w/120V heating element controlled by an industrial PID control. The AC has heat strips but most space heating will be provided by a diesel-powered air heater (5kw) from the F350 diesel tank. Taking out the 2-7gal propane, furnace, and range should get me back ~200 lbs (dry). No specific plans yet on replacing the fridge freezer with a compressor unit but that is on the horizon.
Thats a quite tidy endeavor Sir!…I’m running 440w solar, and a pass-thru ProSine 2.0 which can even muster up the 11.5kbtu air cond for short periods… But I just can’t help being a bit curious about your camping style, and objectives, and how you sourced your leaf batteries, which would seem somewhat costly…
AM Solar lists 400 mA lithium battery system as a total of 180 lbs using the space of 2 batteries. Not sure of the specifics, but eliminating propane and a generator would eliminate a lot of space/weight. Using Truma/induction cooktop would involve an inverter, (not sure how big needed with Truma?). I would only count on enough solar to keep the frig going, which might be a challenge living in the pacific NorthWet. Besides $$ (which would not be spent on gas/propane/generator), what makes this impractical?
Traditionally all electric systems required a good number of batteries which brought with them weight and the need to be charged. The rule of thumb was you did not use electricity for heating and cooling given amp draw. Having propane on board takes care of heating and for most truck campers a 2,000 watt genny can do battery recharging plus run the AC. Mine weighs 45 pounds.
Since you mention AM Solar, I knew Greg Holder, the founder of AM Solar pretty well since he and I spoke at Life On Wheels conferences and he used to refer customers to me on occasion to assist with their solar installations. If you ever saw his Winnebago motor home which was his rolling test bed, the entire roof was covered in solar panels, however, he still used to say when choosing between a generator and solar, go with the generator first as it provides the most flexibility with the least expense. In the example above it strikes me that 400 pounds of batteries plus an inverter is not able to do what a small genny does costing $1,000 or less.
It is not that you can not make an all electric camper. That has and is being done, as Mike pointed out. It does not come cheaply however or else requires adjustments to lifestyle. As with all things RV, you can have anything you want, if you are willing to pay for it. For a good many folks, dollars still weigh heavily in component and camper selection:)
Steve and Andra
2012 F350 6.2 gasser SRW LB
Fab Fours front and rear in case we run into a rhino
2019 Northstar Laredo SCNot having a onboard genny, my ‘wiz-bang’ goal (minimalist objective by comparison!!) was to be able to run the 11.5kbtu for short periods during brief roadside ‘sandwich building’ sessions. Yet upon compressor start-up, this does require a bit of ‘heavy lifting’ (inverter surge capability, current in-rush) for an electrical system that has only two 6v GC batteries – though the 440w of solar does help to augment this scheme, and later provides a reasonably rapid recovery of the batteries…
With the fan running continuously on Lo speed as the compressor cycles off and on, typically the two batts will drop to about 60-50% state of discharge (SOC) after about 1.5 hrs run time, though run times are seldom of that duration…
Beyond this, at higher altitudes when the genny performance drops off, the voltage sensing inverter (a pass-thru type) briefly provides the required extra boost during each compressor start-up (a few seconds of surge condition), then load shifts back to the genny once the rpm recovers…I see this as a kinda virtual generator assist…
Phil,
I think a lot depends here on on where and how you camp. Our 2000 Yamaha had no problems with the AC in the Tetons and Glacier. Last week in Missouri a 90 minute run time would have left us sweltering in 90+ temperatures.
I am not sure I am following. You mention load shifting back to the genny, but I thought you didn’t have a genny?
Steve
Steve and Andra
2012 F350 6.2 gasser SRW LB
Fab Fours front and rear in case we run into a rhino
2019 Northstar Laredo SCHi Steve, Yes I have a Honda 2000, but seldom use or need it except for longer term off-grid air conditioning.
Phil
I have an XP with 3 x 180w solar panels and 600 amp hours of battery life at 12v made up of 2x [2 x 300ah 6v].
We currently get way more solar than we need but when we were in a less sunny situation we used to get down to around 85% of our available power storage overnight, re-charging during the day but reducing an extra 5% each day we stayed in one place and were not receiving power from the truck s0, 85, 80, 75, 70% etc overnight.
We use a diesel cooktop – which still uses some electricity for the fan etc, and also diesel heating / hot water, which still uses electricity to move the air around. Both are Webasto.
We considered an induction cooktop but it would have been the only appliance that required more than a 1000w inverter, so we didn’t bother with the upgrade. The induction cooktops take a lot of juice but they do have the benefit of cooking extremely quickly, offsetting the power use. If you are a heat up and eat kind of cook then great. If you are a simmer kind of cook then not only does the induction use a chunk of power but it is also on or off; it pulses. So no simmer, just boil / off / boil / off .. repeat. Other XP owners have induction and like it though.
I think, in answer to your question, an all electric rig would be fine providing you had a decent battery pack / solar and had a decent bit of time on the road every other day to do the initial battery bulk charge, letting the solar top off the rest. Whether it would work would depend on drive time / solar ability in relation to your power useage.
On a side note, we plug in every month or so just to actually get the batteries to full charge. The charging cycle means that even driving daily and full sun solar, will not get you to a true full charge, which takes hours of continual small current.
2007 Dodge 3500
[5.9 Cummins, Stick Shift] + [XPCamper V1E]I was really on another page with this thread. I interpreted “all electric” to mean a camper without a genny or burning hydrocarbons. To me that meant lots of batteries, solar, maybe wind power, and then off the alternator while driving. Obviously that can be pretty limiting.
Once you throw gasoline, diesel, etc. into the mix I have never defined it as all electric, but I am thinking that is just me and maybe not most other folks. We just spent a few days up in a National Forest in Virginia this past weekend until yesterday and we totally shaded which meant we were about 15 degrees below what it was at our house in Tennessee. We have a lot of places like that where we camp so even though I am a great respecter of solar, it often just is not very useful. So we used our genny when necessary to recharge, but not using our AC, that is seldom necessary or for long. 🙂
Steve and Andra
2012 F350 6.2 gasser SRW LB
Fab Fours front and rear in case we run into a rhino
2019 Northstar Laredo SCUnless you are going to forgo AC, microwave, and any other heavy draw 120-volt appliances, you will need a battery bank and a good size inverter along with running your truck engine in order to keep your batteries charged.
Most often when folks talk about “all-electric”, what they really mean is substituting something else that burns hydrocarbons (gasoline or diesel) to take the place of propane. The reason propane has endured is it is simple, relatively inexpensive, and doesn’t require running an engine except when it comes time to get the tank refilled.
A generator provides a simple way to recharge batteries even when the sun takes a day off. 🙂
Steve and Andra
2012 F350 6.2 gasser SRW LB
Fab Fours front and rear in case we run into a rhino
2019 Northstar Laredo SCNot interested in a generator if I can avoid it. I notice that some class Bs are sold with “underhood generators” AKA a second alternator. Some pickups are sold with “heavy duty alternators”. Equivalent? Bad idea? Find it odd that I don’t see it mentioned in truck camper discussions.
I am not an auto electrician by any means but from what I understand, with my solar at least, the AGM batteries do not simply take on board whatever is thrown at them.
There is an initial BULK charge, a ton of solar or charge from your truck alternator for example satisfies this quite well. This accounts for 80% of the battery capacity. After this initial bulk charge the batteries want less, the controller reduces the charge accordingly and it enters an ABSORBTION stage. At this point even if you have a truck running and a ton of solar the batteries do not use it, they just want a smaller amount. This accounts for just under the final 20% of battery capacity. After that you end up with batteries requiring even less. A FLOAT charge that takes ages and take the batteries up to around 100%. Then there is a final stage that you will rarely get to unless plugged in, so we plug in to shore power every 6 or 8 weeks to get that final bit overnight that keeps the batteries in good condition.
So … having a heavy alternator will help if your truck doesn’t provide much bulk charge at the start. But after that, the benefit tails off significantly. That bulk charge accepts a lot of juice quickly. This means that you don’t actually need much solar to continue those later stages of charge. If you had full solar amps you wouldn’t be using it.
If we have a drive in the morning and ok solar during the day then we are back up to 100% (but not ‘full charge’) by the evening.
A basic explanation from a relative novice. Happy to be corrected by someone.
2007 Dodge 3500
[5.9 Cummins, Stick Shift] + [XPCamper V1E]Unless you are going to forgo AC, microwave, and any other heavy draw 120-volt appliances
Yes 🙂
Does a microwave actually use that much? 1500w would be 125ah inverted from 12v (?)…. if you reheat something for 2 minutes that’s only around 4 amps used. A high power device but short usage. AC on the other hand …
2007 Dodge 3500
[5.9 Cummins, Stick Shift] + [XPCamper V1E]It is often helpful to verify actual amp output from the truck to the camper batteries. In many cases it can be a good less than folks anticipate. Thus the rationale for much heavier cables from truck to camper by many owners.
I think the best way to decide what does what is with a meter capable of measuring amp draw. The rule of thumb in the RV industry has always been not to use inverter power to heat or cool. Brief microwave use can skirt around that rule, although a lot of stuff that goes in our microwave takes a good bit longer than 2 minutes. As with everything RV, “it just depends”.
On the big high end buses I worked on, which I think can actually approach “all electric” for a brief period of time they have 10 of those 125 pound batteries and two 3,000 watt inverters. 🙂
Steve and Andra
2012 F350 6.2 gasser SRW LB
Fab Fours front and rear in case we run into a rhino
2019 Northstar Laredo SC
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