A smart way to build... the Minimum Viable Build (MVB) Method

[afblangley]

I'm curious what you all think is comfortable and uncomfortable?

For me, comfortable means:

• The ability to stand up in my vehicle
• A fridge stocked with cold drinks and food I like to eat
• The convenience of a microwave
• A comfortable bed to sleep on
• A comfortable seat to sit and work or relax
• My own personal toilet
• Access to a sink and running water
• Enough electrical power to run everything I want to use
• HVAC so I am neither too hot or too cold
• Sufficient space to carry the stuff I want

A sunshower works great for washing dishes or yourself. Cook outdoors on a propane stove. The toilet is outdoors too.

I travel a lot and most of my activities are conducted in areas where it is not acceptable to cook, shower, or use the outdoors as a toilet.

Adhering to the MVB philosophy, I implemented the simplest acceptable versions of my requirements. It took very little skill, time, or money. I hit the road and am making refinements as the need arises. Based on my experience, I’ve learned that I need to improve my HVAC, incorporate an indoor shower, and a means of heating water. I'm currently researching the simplest implementations of these.

 

[afblangley]

I'd love to have one. They are very convenient and solar is cheap electricity, but I'm trying to understand if the $1,000 ones only last a couple years.

The price of power stations is not based on battery chemistry (how long they will last). Power stations are priced based on capacity: the size of the battery and inverter. For example, the Jackery 1000 cost $1000 and has a 1000Wh battery and a 1000W inverter, while the Jackery 500 cost $500 and has a 500Wh battery and 500W inverter. They have the same battery chemistry, so the larger one will not last longer than the smaller one. By comparison, the Bluetti EB150 cost $1100 and has a 1500Wh battery and 1000W inverter. It’s battery chemistry allows it to last a lot longer than a Jackery.

 

[rruff]

They have the same battery chemistry, so the larger one will not last longer than the smaller one.

Actually if your use is the same for both, the larger one will last longer... because discharge/charge cycle is a smaller % of its capacity. 1,000W-hr would last twice as long as the 500W-hr in that case.

Are you saying that the numbers on that page are not indicative of how long power stations last when based on actual usage? I mean, do the $1,000 power stations last a lot longer than 1.88 years? They last many years longer if you only need them to charge cell phones and lights? But if you use them to charge a frig & TV plus the other small things and daily run to max allowed, then the numbers are accurate?

I'd love to have one. They are very convenient and solar is cheap electricity, but I'm trying to understand if the $1,000 ones only last a couple years.

Carla, note that the lifetimes given in the article are for 80% depth of discharge. In other words the smaller 500W-hr Jackery would be supplying 400W-hr/day. If you use it every day but only use 200W-hr, it will last twice as long.

Most people who buy these are not fulltime in their rigs, but are rather just using them for a few weekend trips per year, so cycle life isn't so important to them. If you are fulltime, buying one with the LiFePO4 batteries (2,000+ 80% cycles) would make sense. I just looked at the Bluetti page and 716W-hr units retail for $599. Note that bigger ones might be hard to lug around. That size weighs 21.4 lbs.

The batteries will also lose capacity just sitting, especially if they are hot. Keep the unit in a cool place whenever you can. EDIT: what I mean is that they lose capacity due to age over years, not that they self discharge. If you charge one of these up it will hold that charge for months.

 

[DougH71]

Carla, start small.

I have a secondary car battery in my van. It’s connected to my alternator with a continuous duty solonoid. Bob has at least one video on doing this.

You may even have room under the hood for that second battery. You’re truck was offered with an optional diesel engine, which usually requires dual batteries. If, not, you can mount it in the truck bed. I’d put it in a sealed box, vented outside. In my van, I mounted it in a plastic box with a vent tube exiting through a hole in the floor. Since the battery is only charging when I’m driving, any fumes will be sucked out the tube.

 

[user 16179]

For me, comfortable means:

• The ability to stand up in my vehicle
• A fridge stocked with cold drinks and food I like to eat
• The convenience of a microwave
• A comfortable bed to sleep on
• A comfortable seat to sit and work or relax
• My own personal toilet
• Access to a sink and running water
• Enough electrical power to run everything I want to use
• HVAC so I am neither too hot or too cold
• Sufficient space to carry the stuff I want

I travel a lot and most of my activities are conducted in areas where it is not acceptable to cook, shower, or use the outdoors as a toilet.

Adhering to the MVB philosophy, I implemented the simplest acceptable versions of my requirements. It took very little skill, time, or money. I hit the road and am making refinements as the need arises. Based on my experience, I’ve learned that I need to improve my HVAC, incorporate an indoor shower, and a means of heating water. I'm currently researching the simplest implementations of these.

That a great list to identify a First World Gizmo Addiction. Check any three items you have a serious addiction.

 

[dhuff]

I'd love to have one. They are very convenient and solar is cheap electricity, but I'm trying to understand if the $1,000 ones only last a couple years.

If this is a concern, look for well-reviewed brands that use the Lithium Iron Phosphate (LiFePO4) battery chemistry. Jackery doesn't yet, as far as I know. But brands like Maxoak Bluetti and Ecoflow are contenders. Also a good idea to check out reliable reviews on the ones you're considering on Youtube by people like Tom on the Hobotech channel, or Will Prowse on DIY Solar Power with Will Prowse.

 

[rruff]

That a great list to identify a First World Gizmo Addiction. Check any three items you have a serious addiction.

The important thing is to identify what you need to be comfortable, and then set out to achieve that in the most efficient manner. When living in your "car" there are always tradeoffs! Weight, space, convenience, luxury, and complexity involve bigger compromises than they do in a home.

I found that I was happy (happier!) with far less than I was accustomed to. But I wouldn't expect everyone to feel the same.

 

[afblangley]

Actually if your use is the same for both, the larger one will last longer... because discharge/charge cycle is a smaller % of its capacity. 1,000W-hr would last twice as long as the 500W-hr in that case.

Theoretically, you're absolutely correct: depth of discharge effects degradation. On a practical basis, it doesn't make financial sense to vastly oversize a battery bank as a means of addressing life cycles. It is cheaper to appropriately size the battery station based on power needs, and replace it when necessary.

I am not a full timer, but my power station remains in my vehicle and there is stuff connected to it. It is exposed to south FL heat, and occasionally below freezing temperatures. It's charged frequently (since its hooked up so that it charges while I'm driving). A constant solar connection would have a similar impact. These real world factors negatively impact battery life.

Here are my numbers as an example. I have a 1260Wh power station. For battery health, I try not to let the state of charge drop below 20%, thus leaving me with 1008Wh usable. I typically use about 300Wh per day, which means I can go 3 days without plugging in or driving. When my battery degrades to 80% of its original capacity, I will have a max of 1008W, maintaining a state of charge of 20%, leaves me with 806Wh, which means I will no longer be able to last 3 days. Even as a part timer, I will feel this difference.

 

[user 22017]

I'm curious what you all think is comfortable and uncomfortable?

Yesterday I bought a used topper and learned that getting in and out of it is very uncomfortable. It is downright painful.

I'll still need it to cover everything I'm hauling around for tent camping, but I hoped to sleep in it, in case I am too tired to set up my tent.

I could easily sleep on the front bench seat of my truck, except the plastic seat belt supports are in the way. Were those added to prevent seat belts from slipping into the seat? Remember having to dig for seat belts?

 

[rruff]

If it's a topper that is the same height as the cab, that is too short IMO. I did that when I was a youngster (30), but when I built one that was tall enough to sit up in that was a huge improvement. Getting in and out of a pickup bed is also not so easy; need steps or something. Building a topper out of plywood and 2x2s isn't hard to do. Use glue and screws, and make sure the exterior is waterproof. Cheap and easy.

If you don't use the seatbelts, just remove them.

 

[user 22017]

If it's a topper that is the same height as the cab, that is too short IMO. I did that when I was a youngster (30), but when I built one that was tall enough to sit up in that was a huge improvement. Getting in and out of a pickup bed is also not so easy; need steps or something. Building a topper out of plywood and 2x2s isn't hard to do. Use glue and screws, and make sure the exterior is waterproof. Cheap and easy.

If you don't use the seatbelts, just remove them.

It's a fiberglass high rise topper. Old, ugly and in need of repairs. Got it at a junkyard for $200. It should have been $50.

Doug found me a near perfect one in Indiana for $300. I probably should have tried for that one.

I found a ladder that attaches to the tail gate. That might help, since it will put me in a standing position when I get up on the gate. Then I just hunch over to get inside. I'll try my full size house ladder today and see if a ladder will help.

This tail gate ladder (in the pic) is at Northern Tool for $56. The one I found swivels so you can climb from the rear, too. Think that one was at Walmart.

Seat belts are necessary, lol. Although, I swear I was wearing one when my car rolled 3 times on the interstate. Yet I was ejected and landed across the two northbound lanes (I was southbound) in a ditch. Happened 20 years ago, but now I have trauma induced arthritis. So climbing around on my knee is painful.

 

[frater secessus]

Are you saying that the numbers on that page are not indicative of how long power stations last when based on actual usage?

There is no way to predict what they do in actual use, any more than predicting what MPG you will get in your car, or how long the engine will last. We have to interpolate based on lab testing. @afblangley accurately told us about those typical lab figures.

Having said that, the way we use batteries can greatly affect their lifespan. Click and Clack used to say "if you want your car to last forever, drive it like you want it to last forever."

Lithium can be babied for maximum life by

• avoid going below 20% state of charge
• avoid holding them maxxed out at 100% state of charge
• charging at sane (not "fast" rates)
• charging/discharging at human-comfortable temps

Lead is babied by

• fully charging to manufacturer spec daily (or near-daily) <-- rare in vanworld, hence battery murder
• holding 100% state of charge as long/often as possible <-- note this is different than lithium

Anecdote: I bought an extremely cheap Li-NMC 176Wh solar generator back in 2017 for testing, and ended up with a free one because of circumstance. Both continue to work in 2022 despite my negligience/abuse. I baby my main power system because it's the one I actually rely on.

 

[frater secessus]

Yesterday I bought a used topper and learned that getting in and out of it is very uncomfortable. It is downright painful.

A grabber pole can make life with a topper much easier. Push and pull stuff in/out so you don't have to climb around so much.

In my case I used a length of PVC with an L-bracket hoseclamped onto the end.

 

[user 22017]

A grabber pole can make life with a topper much easier. Push and pull stuff in/out so you don't have to climb around so much.

In my case I used a length of PVC with an L-bracket hoseclamped onto the end.

Thank you Good idea. My son-in-law bought a truck that came with a big wooden sliding drawer. He said I can have it. I'll take a look at it this weekend. I like your grabber pole idea more.