so our ARES group has a county-level exercise coming up in about 3 weeks and im trying to figure out the best power setup for running a station out of the back of my truck for probably 18-20 hours straight. we'll have an IC-7300 and a second radio for VHF packet, plus a laptop running Winlink.

right now i've got a 100ah lifepo4 battery and a 30 amp pwm solar controller with a couple 100w panels but honestly i'm not sure that's gonna cut it if we get cloudy weather or need to run the 7300 at higher power for any extended period. someone in the group mentioned bringing a eu2200i honda but nobody wants to deal with fuel logistics or the noise at a hospital parking lot which is where we're staging.

thinking about maybe picking up a second battery and doing some kind of parallel bank but i'm also wondering if anyone has done the math on realistic draw for this kind of thing. the 7300 at 100w output is pulling what, around 20 amps? and that's not even counting the laptop and the vhf rig. just trying to figure out if more batteries is the smarter play than adding a generator to the mix.

also separately - what are people using for portable HF antennas in a parking lot environment? we usually throw up an EFHW but last exercise the feedpoint was way too low and we got complaints about RF in the shack.

yeah 100ah lifepo4 is gonna be close but probably not enough for 18-20 hours of real operation especially if the 7300 is doing any heavy lifting. at 100w out you're looking at roughly 20-22 amps draw on the radio alone, more like 4-5 amps on receive, so it really depends on your duty cycle. for emcomm stuff we usually estimate around 10% transmit which helps a lot but even then the laptop is gonna be a constant 3-5 amps depending on screen brightness and what its doing.

our group went with two 100ah lifepo4 in parallel plus the solar and it works pretty well as long as clouds dont kill us. the honda eu2200i noise thing is real, we had an incident at a hospital EOC exercise where they asked us to shut it down. inverter generators are quieter than regular ones but still not silent. if you do end up needing a generator look at the eu1000i, its noticeably quieter and fine for battery charging if you're not running everything directly off it.

for the EFHW problem - are you using a mast or just a rope throw? we use a 31ft jackite pole for the feedpoint and run the wire out at a slight angle, keeps the feedpoint up around 25-28 feet and the RF issues pretty much disappear. squid pole works too if you have one. the low feedpoint thing is a classic problem with parking lot deployments.

the generator vs battery debate is one of those things that depends so much on your actual use case. for pure emcomm/message handling the duty cycle is usually low enough that a good battery bank carries you through. its when people start doing extended NVIS nets or running digital modes continuously where things get sketchy.

one thing i dont see mentioned - what's your solar panel situation physically. two 100w panels at peak is maybe 10-11 amps real world which is barely keeping up with a receive-only station. parking lot deployments are tough for solar angle too unless you can prop them up on something. ive been experimenting with a 200w foldable panel on a little adjustable stand and that made a noticeable difference in recharge rate between contacts.

anyway i'd say go with a second battery before the generator for this particular scenario. parallel the two 100ah packs, keep the solar topped up between busy periods, and stash the honda in the truck as an emergency backup if everything goes sideways. best of both worlds and you dont have to deal with fuel unless you actually need it.