"All Electric" vs propane . . . ??

[danbr]

We are starting a new Sportsmobile based on a Transit (350, AWD, Long-EL). The current debate is between going "all electric" (no propane at all) vs. retaining the propane for cooking and heating. Note that either configuration will include a generator, 200w solar, and 400Ah battery capacity (or 300Ah Li) and a microwave/convection combo oven.



So far my thoughts are:


"All Electric" Pro:

• Simplified system - one less fill up to do.
• Heating is done via a 12000 BTU gasoline Espar which runs off the main tank - much longer run-time.
• If I run out of battery capacity, I have heat, but no cooking (and recovery options with the genset).

"All Electric" Cons:

• Induction cooktop uses a significant portion of battery capacity for a normal day's cooking, so we are likely to deep-cycle the batteries on a regular basis. Obviously less of an issue if we go with Li.
• Requires a larger inverter to power the cooktop - even the 2.8Kw is probably not enough to run the cooktop and the water heater simultaneously.

Propane Pros:

• Lower power usage means no worries about power for longer off-grid times.
• When we're not using the heat, we have almost unlimited cooking times.

Propane Cons:

• Heating run-time is limited (<60 hours on a full 8G tank).
• Running out of propane means no cooking OR heat! Only recovery is a refill.

There are clearly a huge number of variables in these equations, including switching to a propane water heater (which is 12000 BTU like the heater), going to a smaller induction cooktop, increasing the house bank size, looking for a larger propane tank, seeing if we can use a Truma Combi heater, etc.


Our current Sportsmobile (2013 Sprinter 2500 RB low roof) has neither cooking nor heat, so we haven't had to balance this out. We cook on a camping stove and heat with a 600w Home Depot heater running off of the inverter .


Any feedback from those who have been there before us would be VERY welcome!


Dan

[eddyturn]

Just a thought on the Espar that if you run out of juice, the furnace may not even operate. Low voltage shutoff and that would apply to the propane furnace as well.

[Pntyrmvr]

60 hours of furnace time sounds like it assumes for a 100% duty cycle. I doubt you'll be over 25% across a period of days.

[danbr]

True - that's the type of background data I don't have :-). I know that a 1500W electric heater is more than enough to keep the current van warm with the overnight temp @32F.

[Wowbagger]

You can get a hydronic Espar system, and that will give you both heat and hot water. That saves some electrical energy.
You can also get something like a small Coleman dual-fuel stove, and use that for cooking (outside, of course). That will run on gas, and will also remove a lot of load on the electrical system. Add in a good cast iron skillet, a good coffee pot, and a good dutch oven, and you should be in pretty good shape.

[danbr]

The Coleman + coffee pot is our current solution :-)) I actually use it inside with the slider open on a regular basis.



I've seen the "Airtronic" Espar (heating only) but I'm not familiar with the hydronic ones - I'll take a look, thanks! The Truma "Combi" is the other unit that I've seen that provides both heat and hot water. I haven't asked Sportsmobile if they'll do one of those, but they can provide the Espar airtronic



Dan

[cthayn]

I can share my experience with an "all-electric" van. We built up an E-350 van with a CCV top. I didn't want to mess with the installation and space of a propane tank, nor with another fuel to worry about. So I went with lithium batteries and use the alternator and solar to keep them charged.

Here is a summary of the electrical system:

> 4 - 100 watt solar panels
> 2 - 100 amp-hour LiFePO4 batteries
> 2000 watt inverter
> 12V 130L fridge
> Webasto Petro Heater
> 2.6 gal HW heater with 12 volt heating element
- The hot water is automatically energized when the battery capacity hits 100%, so most of the time it is heated with "excessive solar" power.

Our experience has been great. We have over 150 nights using the van. Our normal travel experience is getting to camp in the afternoon with the batteries at 100% and the HW tank full of hot water. We cook our dinner, run the fridge, use the lights, etc in the evening. Quite often we are in the mountains so we run the heater for a few hours in the morning, before we get out of bed. Usually by morning the battery is at 60-70%. If it's a sunny morning, the battery is back to 100% by 9 am. We usually drive each day, so even if the sun is not out, the batteries are fully charged after an hour of driving.

Here is a recent real life experience:

Just last week we were camping in southern Utah and ran our batteries down to around 30% by morning. That is the lowest state-of-charge we have ever been.

We used a lot of electricity that night and morning. Dinner was cooked on the induction cooktop and the InstaPot. We heated enough water for both of us to take showers. My wife blow-dried and straightened her hair (I know??). It was got dark and cold early that evening, so we ran lights for most of the evening. The Webasto heater ran 6-8 hours that night and morning. Breakfast was pancakes, cooked on the induction cooktop. However, it was cold, so the fridge didn't have to run too hard.

Plus, we were camped in a narrow canyon, so the morning sun never did hit our solar panels before we left camp, so no recharging from the sun.

This was the most electricity we had used in one night of camping, and we still had 30% left (however, I don't think I would ever run it to zero).

So, in summary, the system has worked great. Solar panels and Li batteries are expensive, but prices are coming down. I don't know if I would do this type of system with lead-acid, or gel batteries. My research determined it would take 4 times the weight and space to deliver the same amp-hours of battery capacity.

You can review my build in my build thread:

https://www.sportsmobileforum.com/fo...top-20698.html

Let me know if you have any questions.

>> Corey

[danbr]

@cthayn -


Thanks - exactly what I was looking for. I read through your build thread too - VERY impressive work. You guys stuck it out through a LONG and careful build.



(Of course) - a few other questions:

• Two-burner induction top? How much does it draw?
• Do you have a battery monitor? I couldn't see one, but it was pretty late by the time I finished reading the thread . . . .
• No genset, correct?
• 3kw inverter, correct?
• With 400w solar, what type of charge rates were you seeing at the deep discharge?

We have 200w and a 440Ah battery bank on our boat; normally that will run our fridge and our electronics and radios on a consistent basis, but because the batteries are AGM we are careful to not discharge below 50%. It takes 3 or 4 days of really cloudy weather before I have to charge the batteries with the engine. The cooking is the wild-card here compared to the boat :-)


Thanks again!


Dan

[86Scotty]

Having done most of this several different ways I think you are spot on with mostly electric and a petrol Espar.

My alternate takes on cooking are these: One way is to permanently mount a nice popane RV stove but fuel it with a 1 lb. cylinder below the countertop. I did this with an SMEV sink/stove (hob) in my Transit and it worked amazingly well. I did not find it to be a dangerous setup at all. Keeping your lp/co2 detector in good order is necessary in any van. Also, I can smell propane!....but I never did. You would be amazed at how long a single cylinder will run a stove.
Second idea is to recess or just use a countertop butane stove ($20 on Amazon for the knockoffs, all of which work well). Then you can take it outside to cook when the weather is fair. This idea appeals to me because no amount of counter space in a van you spend much time in is ever enough. You can remove and store one of these when not needed and free up counter space.

[bigriver]

I'm with Eric. We have a counter top two burner propane stove installed and use the one lb bottles with no problem. We have a flex hose that runs from stove under the sink where the bottle is kept. One bottle goes a long way. Great easy solution.