Testing our limits

Today marks the end of our longest boondocking stay so far, 14 days and 13 nights. The goal of this trip was to test our limits and see how easily we can handle two-weeks off-grid. And overall things went very well.

(Editor’s note: the next few paragraphs go into detail on our water, propane, and power use so if that’s not your thing you might want to skip down to the pictures of Carlsbad Caverns).

We started the trip with a full tank of freshwater (93 gallons) and 18 gallons of drinking water (split between a few different containers and jugs). As of this morning our freshwater tank just flipped from saying 1/3 full on the sensor to saying empty – which really means we probably have about 10 to 15 gallons still in the tank. And we have about 3 or 4 gallons of drinking water left over. So, as far as water, we have no issues at all going two weeks and we probably could go a couple more days with the amount we brought with us.

We also started the trip with three 30-pound propane tanks completely full. We went through one and have about 15% left of a second tank, with the third tank completely untouched. When we were boondocking over the summer months we averaged depleting our propane tanks at about 10% per day, but that increased to 15% per day during this trip – due to running the fridge on propane a bit more to account for fewer hours of sun and running the furnace most mornings to warm things up.  But, even with the heavier winter use, we still got about a week per tank and with three tanks we can easily make it two weeks off-grid and could probably get close to three weeks before hitting empty.

As for the solar, there are definitely fewer peak sunlight hours in the winter and with the sun not getting as high in the sky the solar panels are not quite as efficient as they are in the summer. We have a total of 2,640 watts of solar panels on the roof (12 panels at 220w each) and in the summer months we can see as high as 2,400 watts per hour being generated by the panels. But on this trip I don’t think we were ever bringing in more than 1,600 watts at any given time.

Also, since we normally see our solar power production pick up about an hour after sunrise until about an hour before sunset, in the summer months we would have good sun most days from about 9am until 5 or 6pm – for 8 to 9 hours of good power production each day. On this trip, however, the peak sun hours only ran from about 10am until 3pm for usually just 5 hours of peak production per day.

All that said, we didn’t have any power issues at all. We started the trip with our batteries (three 24 volt, 100 amp hour lithium batteries with about 5,000w of storage each) at 100% and, as of this morning, we’re only down to 50%. To compensate for the fewer peak solar hours in the winter we kept the fridge on propane a few more hours per day that we would in the summer. That helped some, and didn’t increase our propane use too much, but we might not have needed to do that since we were never really in any power trouble (and are ending this trip with our batteries still half-full). We did have mostly sunny days these two weeks, so maybe things would be different if it had been cloudy most of the time. But, especially with a generator for backup, I think power is the least of our off-grid worries and making it two weeks is a breeze.

So, water, propane, and power don’t seem to be limiting factors at all. Even if we ran out of fresh water we have a portable 60-gallon bladder that fits in the bed of the truck that we could drive into town to fill up and use the on-board water pump to get that water into the fresh tank. We could also take empty propane tanks into town to get them re-filled, and as long as there are a few hours of sun each day we can replenish our batteries to some degree. I’m not sure I’d go so far as to say water, propane, and power are limitless but I think we can easily go multiple weeks before any of those resources become an issue.

That brings us to our one, true limiting factor – the waste tanks (and one tank, in particular).  I think we can probably get close to three weeks on our black tank and there are always ways to mitigate filling that tank up (bushes, shovels, being one with nature, etc.), so that tank isn’t a major issue. And the 50-gallon grey tank connected to our kitchen sink hardly gets used at all. When we’re boondocking we often use a collapsible bucket in the sink to catch the dishwater before it goes down the drain and then we toss that nightly as if we were tent-camping.

But then we have the 50-gallon grey tank connected to the bathroom. That tank collects all the water from showers and the bathroom sink (brushing teeth, hand washing, etc.). Even when we only shower every other day (and take very short military showers) while boondocking I don’t think we can get much more than two weeks out of that tank. It didn’t overfill on this trip, but I have a feeling we’re pretty close to full. And unfortunately there’s no easy way to empty that tank without moving the 5th wheel out of a boondocking spot to a dump station or dumping large amounts of wastewater into nature, and that’s not something we want to do (and it isn’t legal in most places).

So, in the end, with our current set-up I think we can expect to handle being off-grid for two weeks at a time pretty comfortably and we might be able to get a couple more days in there but three weeks might be asking too much out of our bathroom grey tank. Which is good. Two weeks per boondocking trip is what we were hoping for and, honestly, about as long as we’d want to be off-grid per trip. Being conservative and constantly monitoring our resource levels can get exhausting and after two weeks of that I think we’re both ready to have full hook-ups again and relax a bit. Plus, after two weeks we both start to run out of clean underwear and I’m not sure I’m ready for trying to find ways to get more out of our limited underwear supplies.

Okay, enough about all that.  On to the pretty pictures…

The major highlight of our second week at this boondocking spot was spending the Saturday after Thanksgiving exploring Carlsbad Caverns. I’m glad we saw the other two caves (Lehman Caves in Great Basin National Park and the Kartchner Caverns outside Tucson, AZ) before Carlsbad since those were much smaller and more intimate experiences. If we had seen Carlsbad first we might have thought less of those smaller caves but this way we got to get up close and personal first and then stand back in awe of the grandiose of Carlsbad.

Carlsbad Caverns was the 21st national park we have visited together and we are now, officially, one-third of the way through visiting all 63 current US national parks. We’re pretty confident we can visit the next third over the next year or two, but that last third might be tricky with most of the remaining parks in Alaska, Hawaii, American Samoa, and the US Virgin Islands.

But those adventures are for another day, today we’ll just be moving up the road about 20 miles to an RV park/campground in the town of Carlsbad. We plan to stay there for about a week before we head down south into West Texas for the rest of the winter. There are a few things we want to get taken care of during our week in Carlsbad, especially since it will be the biggest town we stay in for quite a while. Carlsbad only has about 30,000 people but that’s way bigger than the small towns (villages? settlements? families?) we’ll find down south. Our first destination in West Texas will be Terlingua near Big Bend National Park, which is known as “The Texas Ghost Town” (but it does have a functioning post office). We won’t be boondocking down there but, with fewer than 100 people spread out over thousands of acres, it will probably feel like it!

2 thoughts on “Testing our limits

  1. Nancy Curtis

    Amazing Carlsbad Caverns…
    any bats???
    I’m at airport in Tucson flying home
    watching the fighter jets take off…
    no sonic booms though!
    Sounds like you have water, power
    and propane figured out!!!
    Enjoy the scenery and thanks for
    the great photos. Still waiting for
    the buffalo to post 🙂

  2. Terry

    Nice update again Scott – learning the limits under “normal” use is essential but then weather variations as you’ve noted with solar radiation can dramatically change energy usage. The good news is you’ve got excess LP and with gen set backup you can maintain necessities. And as always great photos – although I was expecting to see bats chasing the buffalo and bat guano on the solar collectors!


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