Inverter Questions

[rvwandering]

I'm posting this for TrailerManNJ who is having a problem starting threads.  rvwandering

Hi ya'll, hope everyone's been well lately. Have a few questions on inverters. As I'm NOT a technically minded individually, please be simple in your answers, just like you were speaking to a 10 year old, so I can hopefully grasp what you're saying lol :thumbsup:

From what I gather, an inverter takes the power that's generated from the car battery and converts it from DC to AC current. This current can then be used to power things like hair dryers, coffee makers, etc...just like at home. But here's where I get confused...

What benefit (if any) would installing an inverter in a car (for camping purposes) have over using something like a Jackery or Bluetti, instead? This is question #1.

An inverter being linked to the car's battery presents several possible catastrophes, IMO. For example, leaving items plugged in and draining the battery, something shorting out and affecting the battery and so forth. If issues like this happened, it seems it would be easier/cheaper to fix on a Jackery versus a car battery. What are the potential dangers/pitfalls of connecting an inverter to the car battery? This is the 2nd question.

More below...

 

[rvwandering]

From a cost perspective, is one option cheaper than the other? I'm not even sure what a mechanic would charge to hook up an inverter to a car. Jackeries and similar units are expensive, but once they're bought, that's all you need. This is question #3.

Does having an inverter linked to the battery in a PRIUS offer any advantages over other vehicles? Question #4.

Finally, I'm not a fan of wires. Especially long, visible ones snaking throughout a vehicle. It not only looks ugly, but presents many hazards, too. Where/how do many of you hide the wiring from the battery to where the inverter rests? Question #5.

My needs are VERY simple. The only large item I'll need constant 24/7 charging for is an Alpicool fridge/freezer. Which draws about 40-50 watts of power. The plan is to hook a roof-mounted 100watt solar panel to a Jackery or similar unit, which in turn will power the fridge. Everything else (laptop, phone, etc.) would only need short recharging once per day, and I can also plug them in the Jackery or use those small handheld power banks.

Appreciate any input

 

[Ravella and X]

I am not electrically literate, either. But I think I understand this well: you wouldn't use your car battery (which is built for starting), you would use a deep cycle battery and call that your house battery.

I think that the simplest way to go would be the jackery or other brand of that kind of thing. However, it may very well be cheaper to install a house battery and a small inverter.

I thought those alpicool fridge/freezers were DC current. If so, you have no need for an inverter at all. Just a solar panel, charge controller, and house battery. You could use your car battery to charge your devices. Oh wait... You have a laptop. Guess you need an inverter after all (pure sine wave, not modified).

If you solar literate peeps have corrections to make, be gentle with me
: )

Edit: if you go with an inverter and house battery, they should be very close to each other with a short short wire run. No long fat wire snakes.

 

[Ken in Anaheim]

The advantage of an inverter in a Prius is, by leaving the Prius in, "on" condition and hooking the inverter (often/usually 1500-2000 watts) to the Prius' 12v battery, you can use as much power as you wish and the Prius will "auto-start" the engine as needed to recharge the BIG battery which in turn keeps the 12v battery charged. Used like this, tests have shown that for an equivalent  wattage generated , the Prius actually uses less gas than a Honda 2000i generator. As long as you have gas in the tank the battery won't get drained.

 

[TrailerManNJ]

Thanks for the info, Ken! Must say, that sounds pretty nifty! Here's a concern that comes to mind though (which might not be warranted)...

When you say leave the car in "On mode", I know that the Prius won't technically be "on" all the time, but instead, will start the engine every 10-15 minutes to recharge the battery. Wouldn't this put a heavy burden on the car, if it operated as such 24/7/365? I'm getting a Gen 2, and I'd be worried about the strain of an older vehicle having to continuously cycle off & on for infinity. Plus the gas burnage to boot (which I'm sure is minimal), but that's another whammy.

Is my concern misguided?

 

[tx2sturgis]

Roof mounted (and horizontal) solar panel output drops significantly in the winter months, with short days and low sun angles, even without cloudy weather.

Figure on 200 to 300 watts (preferably tilt-able or portable) to keep that power pack and the fridge happy.

It's not reasonable to use the Prius 24/7 in idle/auto mode. Maybe use it that way when needed (very cold or very hot nights) but certainly not all day and night each and every day and night.

 

[eDJ_]

I've been hard at work on my rig the past few weeks.  Finally some weather where I could.  I looked at the cost of the Jackery 1000 with solar panels and it's pretty rich.  In my E 350 Van I'd be better off with a deep cycle 12 volt dc house battery installed and an inverter set up to run off it.(for my 12 volt dc needs) 

A couple of friends of mine have purchased the Prius cars (since I see Prius cars being mentioned here) and set them up to double as a house generator for their homes.  The Prius is literally a mobile generator as it is.  Most larger inverters have a cigarette plug access for lower power devices (provided your car has a cigarette lighter)  but to get the higher power they are capable of, the inverter has heavier wiring terminal connections that connects directly to the battery.  

There are automotive electrical shops who could run proper wiring under the car to provide the connection ports you need in the car.  They can do it in a professional manner and use large fuses so that electrical hazards will be minimized and you'll be safe.  No wires in sight the way you would like it.  The inverters have fuses, circuit breakers, fans etc built in and would be capable of shutting themselves off it overloaded. (depending on what you purchase) 

What you are wanting to do is entirely possible and since a Prius is like a rolling Jackery anyhow think about a pro installed inverter if you have need of AC power.  As for your domestic appliances there are 12 volt sites that sell a vast range of 12 volt stuff. 

12Volt Travel com

 

[TrailerManNJ]

Thanks to everyone for the replies, please do keep them coming :thumbsup: 

Have to say, now that I understand what an inverter can do, and how having one in a Prius is even better, it sounds like a great set-up. However, as tx2 said, not sure how practical it would be to keep the car continuously operating indefinitely in "ON MODE" just to power a fridge. Especially with an older vehicle, which is already a gamble.

I can totally understand starting a vehicle and letting it run for an hour or two per day to charge devices, but the constant 24/7/365 of a 10+ year old car restarting every 10-15 minutes seems like it would eventually wear on it in some way, shape or form.

Unless someone can convince me otherwise, for MY application, a portable battery pack like a Jackery hooked up to a solar panel appears to be the superior solution.

As for the cost, yes, Jackeries and units like them are expensive up-front, but you get what you pay for. Further, I consider it an investment. From what I understand, the portable battery stations generally only last for 4-5 years before you have to replace them. Even going on the low end of 4 years, if you do the math, a $500 Jackery will come out to about $10 per month. How in the heck could you argue with that for the luxury of electricity...which would cost about 10-15 times that per month in a stick & brick?! 

 

[tx2sturgis]

As for the cost, yes, Jackeries and units like them are expensive up-front, but you get what you pay for. Further, I consider it an investment. From what I understand, the portable battery stations generally only last for 4-5 years before you have to replace them. Even going on the low end of 4 years, if you do the math, a $500 Jackery will come out to about $10 per month. How in the heck could you argue with that for the luxury of electricity...which would cost about 10-15 times that per month in a stick & brick?! 

Actually the math is: KWH (kilowatt-hours) we buy from the grid is MUCH cheaper per KWH than the KWH we can make with solar panels and batteries....at least, over the short term and in small quantities.

But your point is valid: If we are cutting way back on what we need, it will be cheap (or at least reasonable) to make that small amount of power and store any surplus in the power pack for later on, at night, during cloudy weather, etc.

 

[TrailerManNJ]

I should've been more careful in my wording, tx2, as you're correct. If I was just using the same tiny fridge in my home, that I'll be using in my vehicle, the cost would probably be pennies as compared to $10 per month...but you got my point. Which is...

I see a lot of people complain about the cost of various camping gadgets, and I totally get...some of this stuff is VERY expensive. But comfort comes with a price. And we all have our preferred comforts. For some people it's having enough headroom to be able to stand up in their vehicle. For some it's eating a certain kind of food. And so on. As for me...

I could care less where I sleep or on what. Same goes for poo & pee. So, no expensive mattresses or composting toilets needed here. My comforts are climate control (which is why I'm choosing a Prius), having the ability to store refrigerated foods, and finally, a hot shower...even if it's just once or twice per week. For that I'll be getting one of the new Rinsekits. Fill it up anywhere, no pressurization needed, and a battery charge lasts about 3 months. Price? $350. But again, if you go back to my 4 year rule (which is surprisingly accurate for most items made nowadays), in the event it went kaput at that time, the cost would be about $7.50 per month, for the convenience of having an on-demand hot shower anytime you'd like.

Now break your last sentence down for me a bit, tx2, because here's where I get confused. Suppose I get a Jackery or similar unit. All of the portable power stations have a digital readout like a cell phone, which feature a battery life indicator...and they all obviously peak at 100%. My question then becomes...

Does that mean that the power station cannot hold/store any more power than that, or is it INDEED storing more power, but just can't show it on the digital readout? For example...if it's showing a 100% charge and nothing is plugged into the unit (no draw) but it's still attached to the solar panel for the next 3 days in optimal conditions, will it's internal capacity hold 130% or 140% for example, or is any overage just wasted?

 

[MrAlvinDude]

Yes, once the battery is at 100%, then what ever comes in from the solar is just wasted.

One way to make use of what is coming in via solar, once the battery is at 100% - is to charge your other appliances, like laptop, USB power bank and what ever else has a battery built in.

 

[StarryNights]

The Rinsekit seems to be expensive for a tank that sprays water; you still have to pour heated water into it. Search Amazon for "battery operated shower pumps" to see $40 solutions; less if you use 12v cigarette outlet one. Combine with 32" folding dog bath and 118" liner and you have $60 quick setup indoor hot shower that folded up stores in small grocery bag.

More: I'm old and do have to sometimes quickly answer nature's calls. DIY composting toilets easily made for between $20 to $100: love mine and rank it one of most indispensable things in my build. My van bed is better than one at home and made from old memory foam mattress.

I live in NH but winter in AZ low desert BLM which pretty much eliminates need for AC. Heat sometimes nice to have; I chose Chinese diesel heater ($125), but lots of other solutions. My fulltime friends have no AC but chase 70 degrees moving to high elevations in summer. Most moving to low desert now.

You do not have to spend big bucks to have lots of comfort!

 

[tx2sturgis]

Once the battery (or power station, power pack, whatever) reaches 100% then charging usually stops. 

Just FYI: Sometimes the indicator could indicate 100%, but maybe the tolerance of the charging circuit indicates anything over 90% as actually showing 100%. This is done for a variety of reasons: marketing, consumer confidence, and future-proofing as the battery declines in capacity. In this case, your readout might show 100% even tho the indicator shows that charge current is still flowing in.

Getting into the weeds: In some cases, lithium batteries are 'slightly' overcharged on purpose...this is called 'top balancing' but it does not charge the cells past 100%, which would damage the cells, but the built-in BMS module will use this excess charge current to route the energy to any cells that are a bit low, so this process will equalize the charge voltage in all the cells so that you truly have 100% charge level across all the cells in the battery.

Typical AGM and flooded lead acid batteries do not always reach 100%, because the 100% value is elusive. A smart charger can ASSUME a certain voltage is a certain level of charge, and we can be sure the smart charger has done it's best, but really, that's all a 'smart charger' can do...is approximate, or guess, that the job is 100% completed.

As far as 'wasting' energy coming in from the solar panels when the battery is 100% charged...nope. The charger shuts off the incoming current, or tapers it down to a minimal maintenance level, but there is no 'waste'...except the sunlight falling on the panel is not used to generate any electricity... like gasoline in your car gas tank that you not using right now.

It's not 'wasted'...its just not doing anything productive right now.

 

[TrailerManNJ]

Starrynights: The new Rinsekit (the one I mentioned), has a heater coil coming out for it in 2022. But even without it, one can add their own hot water, or just leave the kit in the sun for a few hours, and let the unit warm up that way. I'm mainly interested in the automatic pressurizing, and the 3.5 gallon capacity. They also have an older model (which is cheaper), though that requires purchasing a hand pump through them to manually add pressure into the unit. At that point I'd be better off making my own shower out of a hudson sprayer or something, which as you say, is a lot less on the wallet. My mind is on the bigger stuff now (securing a good car, having it inspected, the build-out, etc.), so I'd rather just bite the bullet on the smaller stuff - even if it means paying more for it upfront. Hopefully it'll be "Just set it and forget it" for the next few years.

Tx2: That makes a lot of sense, thanks for breaking it down for me :thumbsup:

 

[Ken in Anaheim]

 Wouldn't this put a heavy burden on the car, if it operated as such 24/7/365? ...

TrailerMan, from what I've ben told, it's quite normal for Prius taxis to run 24/7/365 (except when they're being serviced) with no ill effects.

 

[jacqueg]

I am not electrically literate, either. But I think I understand this well: you wouldn't use your car battery (which is built for starting), you would use a deep cycle battery and call that your house battery.

I think that the simplest way to go would be the jackery or other brand of that kind of thing. However, it may very well be cheaper to install a house battery and a small inverter.

I thought those alpicool fridge/freezers were DC current. If so, you have no need for an inverter at all. Just a solar panel, charge controller, and house battery. You could use your car battery to charge your devices. Oh wait... You have a laptop. Guess you need an inverter after all (pure sine wave, not modified).

If you solar literate peeps have corrections to make, be gentle with me
: )

Edit: if you go with an inverter and house battery, they should be very close to each other with a short short wire run. No long fat wire snakes.

My Alpicool came with two cords/plugs - one is for plugging into AC, the other for DC. 

Totally agree with not running long wires in a van.

 

[TrailerManNJ]

Ken: I can believe that about the taxis, but you don't know my luck. If I bet on both black AND red at the roulette table, I'd still lose. When I get the car it will be treated better than an elderly nun on Easter Sunday  :thumbsup:

 

[tx2sturgis]

TrailerMan, from what I've ben told, it's quite normal for Prius taxis to run 24/7/365 (except when they're being serviced) with no ill effects.

That kinda depends on how you define 'ill effects'.

Taxi service is rough on ANY vehicle. They will typically reach end of life in a few years (with several hundred thousand miles) versus a few decades when used as a private vehicle.

 

[StarryNights]

TrailerManNJ - ok on better unit coming out with heater. Check power draw! I just heat water on stove and dump into collapsible bucket, adding some cold till temp just right. Submersible pump then provides great hot shower. Inexpensive and takes up tiny space.

But, you are right to concentrate 1st on finding the correct van before buying components. I looked 1.5 yrs before making buying decision, then over a year slowly researching components and building. It is work, but in the end really rewarding.

Sent from my LM-V405 using Tapatalk