could use some help with my electrical usage estimation...

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AlexK90

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I tried to work out my electrical usage, but it's adding up to be rather high (even though I accounted for a compressor fridge and a Fantastic Fan).  Did I make a mistake, or does this look about right?  What would be the best way to reduce my usage?  The Cintiq and external monitor are both things I use for work so it's kind of important for them to stay.

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It's looking like I would need 350-400 watts of solar, which is ok, but I'm concerned about the battery bank.  I'm buying a Yeti GoalZero 1250 generator (I know people aren't fans, but I'm getting it used at a good price).  The capacity for that thing is 1200 Wh, 100Ah, 12v.  Would I need to wire another battery in parallel for it to work?

Any advice or feedback much appreciated.
 

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For that kind of setup the Yeti won't be nearly enough. Sam's or B+ Duracell Golf Car 6v x2 will give you 200+ AH for <$180. With the fridge to be honest I'd say get two pair.

Get the Yeti too if it's less than that and offers something special for your use case, just make sure you get the main bank charged 100% each cycle.

You will likely need to either regularly get onto shore power overnight, or consider getting a little suitcase generator to supplement solar.

Make sure to use straight DC for your charging, only go through the inverter when truly necessary.
 
Could the router be turned off at least when you sleep?  I think your fridge and fantastic fan estimates may be high.  I got a 1.7 cu ft Haier dorm fridge for my mother in law at the assisted living and it is only 330 watt hours per day.
 
It looks about right, but I would divide the chart into day and night usage.

Figure out what devices will be used and for how many hours during solar gain (daytime) and then another chart for the overnight usage during the night time when you are on battery only. There needs to be some reserve during the day for charging the batteries or you will not make it thru the night, and then you will fall behind on charging the next day.

The more electrical usage you can 'move' to daylight hours, assuming the solar panels can keep up, and still have some reserve, the more capacity you will have at night.

Make sense?
 
I have a couple of questions,
what is a cintiq?
8 hours of lights, are they LED? seems to much turn them off?
phone charger, seems like a lot? I only charge my phone every 4 days.
fridge seems way high, what kind of fridge?
hair dryer, skip it everyday where are you going to get that much water?
blender get a 12v.
router, this one really has me curious why do you need a router?
highdesertranger
 
highdesertranger said:
router, this one really has me curious why do you need a router?
AKA a hotspot, but also like traditional Ethernet wired.

If you have several devices that connect to the Internet and one unlimited data sim, much more convenient than juggling multiple accounts.
 
highdesertranger said:
I have a couple of questions,
what is a cintiq?
8 hours of lights, are they LED?  seems to much turn them off?
phone charger,  seems like a lot?  I only charge my phone every 4 days.
fridge seems way high,  what kind of fridge?
hair dryer,  skip it everyday where are you going to get that much water?
blender get a 12v.
router,  this one really has me curious why do you need a router?  


Hey highdesertranger!  The Cintiq is basically a monitor you can draw on (like an interactive computer screen).  I use it for work.  The router is for internet, which I also need for work, but another user suggested turning it off when I sleep which is a good idea.  I could probably charge my phone via the cigarette outlet in my van.  
For the fridge I tried to estimate for a Dometic CFX 35us (I don't have one but I'd like to get one if I can find it at a discount).  Estimating the wattage is tricky because from what I can tell it depends on what's in the fridge...I ballparked the estimate so it may very well be too high.
Worse comes to worse, I can skip the fridge and do a cooler instead...
 
That's a good idea (turning it off when I sleep)! And yeah I'm thinking my fridge estimate was probably a bit too high.  I can probably revise this and shave off a few watts...
 
I understand the for work stuff but after that the fridge would be at the top of my list. buying ice for a year would more then likely pay for the fridge. highdesertranger
 
Your numbers for fantastic fan are too high.  3 speed fan on 3 (high) = ~ 22 watts (1.8 amps).
My MaxxFan on 8 of 10 uses 34 watts.  I only run it that high when I want to clear out the camper fast.

My old Norcold refrigerator uses < 300 watt-hours per day (24 amp-hours) with outside temps between 70º and 80ºF.  It has 3" of added isopoly insulation around the sides, is kept full, and has adequate ventilation for the condenser.

 -- Spiff
 
Thanks for the tip about the fridge!  I'll be sure to insulate it..

I re-estimated it to be lower, but the battery bank still looks like it'll have to be around 540Ah.  The Yeti only has a 100Ah battery...do I need to get more and wire them in parallel?  Or will the one battery be able to handle it?
 
You started at 130 amp hours.  You re-estimated to be lower at 540 Ah.  Could that be your re-estimated watt hours so only 45 amp hours?  That's within the 100 Ah capacity of the 100 Ah Yeti.  If you can charge it back up daily that doesn't sound like a screaming need for two of them.  What is the recharging plan?
 
you can't or I should say, you shouldn't mix batteries of different types and/or ages. highdesertranger
 
Just no way one Yeti will run all that, and they are so pricey per AH building a bank out of them is nuts.

See my previous post, 4x Sam's 6v should be plenty. Then can use a Yeti as a secondary aux portable unit, just not the main bank.
 
Spaceman Spiff said:
Your numbers for fantastic fan are too high.  3 speed fan on 3 (high) = ~ 22 watts (1.8 amps).
My MaxxFan on 8 of 10 uses 34 watts.  

The 3 speed Fantastic Fans that have a resistor network to control fan speed DO use more power...I'm thinking its double or triple the amount you posted.

I'm not able to check this right now tho...so I could be remembering the numbers incorrectly.
 
tx2sturgis said:
The 3 speed Fantastic Fans that have a resistor network to control fan speed DO use more power...I'm thinking its double or triple the amount you posted.

I don't have a Fantastic Fan, I was just relaying numbers from an acquaintance.  He used a clamp-on ammeter, my numbers for MaxxFan are from a Trimetric.  FF top speed seemed slower than MF.  I too could be wrong (though it's never happened before  :p ).

 -- Spiff
 
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