Would like your input -

[teesquare]

This fall I have an Elk hunt planned. But unlike every other year - I am horse-packing in 5 mile beyond the trailhead, and setting up basecamp. So there are 2 issues I need to solve:

1. I will be completely off the grid for 12 days. Need power storage battery that is nota heavy, lead acid type. I have seen the solar battery back up type which have ports/outlets for 120VAC as well as USB, etc...but I need to find out how to calculate the correct size  unit needed.I will be using a ResMed Air Mini I think Still deciding... but it seems to be the best for overall size). Small, compact and light are the priorities for packing everything in. There is a 150 lb. weight limit per person. 

2. Base camp is at  a little over 10,000 feet about sea level. I know that CPAPS are able to auto adjust - up to 7500-8500 feet, depending on model. Is there a way to off set the difference in elevation by increasing the pressure just a little? Or....?

Thanks for any response.
T

[Sleeprider]

Here is a source to estimate your power needs https://document.resmed.com/documents/ar...lo_eng.pdf
I would not change up too much for altitude. At 6 amp-hours 24-volts DC you are at 144 watt hours per 8-hours of use that needs to be replenished with solar or other additional li-ion battery capacity. 12 days x 6 AH/day = 72 AH for the trip. I don't have experience recharging li-ion with solar, but it seems you could maintain the battery(s) with a 40+ watt solar charger. Keep the flow generator inside the sleeping bag and don't fart...I mean the air will be warmer, and you can use the HME (heat moisture exchanger) that comes with the Airmini masks.

[teesquare]

THANK YOU Sleeprider!

A lot to consider....The "flow generator"...meaning the CPAP machine itself? As far as farts......will be a challenge. Camp food can often replicate the scene from Blazing Saddles.....

T

[Sleeprider]

Well, yes! Not to mention the effect of altitude on the gastro-intestinal track. I use the term flow generator for the component that has the fan. Of course the AirMini is almost entirely fan. I had not realized how efficient it is on battery power compared to the other CPAPs.

Whatever you decide on, the best idea is to give it a trial run and see if it fully recharges in a day, before you find yourself in the middle of nowhere.

[teesquare]

Absolutely. Will trial it IN the sleeping bag before I commit to this as a solution.

[Sleeprider]

You can keep the machine outside the bag, but in that altitude it's going to be cold and you're going to feel that even with the HME. Your trial needs to focus on battery use and recovery with with whatever charging system you plan to use.

[teesquare]

Understood. Will be in a tent - with wood fired heating, but the temp will obviously drop precipitously after everyone falls asleep and the fire is not being tended.
T

[Sleeprider]

Teesquared, something you might want to look at is the Antigravity PS-45 Portable Power Station. They are a high capacity power bank by a very reputable manufacturer of batteries. The word is, this will power a standard Airsense 10 or S9 CPAP for a full night and only use 25% of the battery, The unit has capability for recharging by solar panel, that is also discussed on their site. The price is really good at under $150 for the power bank, and it has 2-DC power outlets, 2-USB and an integrated inverter to an AC plug. It's not tiny at 6"x6"x3" and 2.86 lbs, but is may be on-target for your needs.

You would pair this with the XS100 solar panel for $229 or XS60 for $159. The XS60 is 6.5 lbs and will charge at 60 watts. The 100 is just over 10 lbs and 100 watts. I think you can get by with the smaller unit, and the PS 45 battery capacity at 45,000 mAh has at least 4 to 5 days of run-time for the AirMini.

[teesquare]

Thank you so much for thst suggestion. I will look into that system tonite, as it sounds like a lighter solution than what I was seeing.
T