Experience with indoor gasification boilers

I have the same boiler as 3fordasho , Attack fox 45 profi. Installed it in 2015 and love it. Never had any problems. I don’t think I would do the unpressurized, I had a central owb before this and hated almost everything about it. I bought mine the year before they came out with lambda control, not sure how much difference it makes.

 

I'm 4 months into researching wood boilers, storage and all the associated components.
My goal is to install a system that burns the least amount of wood with little to no smoke or creosote and is cost effective to install, maintain, repair and will last 40 years without replacing entire components.
OWB's and their indoor cousins without storage have evolved and become very effective at grabbing as much heat out of the wood and putting it into the house. Lack of storage means the unit re-fires each time there is a call for heat. This reduces efficiency somewhat and causes some smoke on startup and some creosote buildup.
Pressurized systems have a clear advantage with little to no water treatment to deal with.
Storage comes in all shapes, sizes and types. Storing and recovering heat in water seems to be the most effective system when you consider space requirements.
I like the idea of storing as much heat as you could use in the worst case scenario for a 24 hour period.
The Garn, I believe, is unique in that it combines a once a day, high temp burn with storage sized for 24 hours. Being an open system increases maintenance costs and the footprint of a 2000 gallon unit 3 times the size of 2000 gallons in an insulated cubic structure.
All of this has me leaning towards a system that consists of:
1. A stand alone, indoor, gasification, pressurized boiler capable of holding 100 lbs of well seasoned wood. Based on my calcs so far of what it takes to heat 2000 gallons of water from 150 to 180 on 1 burn.
2. Water storage in an insulated, unpressurized, cubic structure with copper coil heat exchangers to transfer heat from the boiler to the storage. A second set of copper coil heat exchangers would transfer heat to the existing gas boiler system and DHW heat exchanger.

Looking for input.
Many thanks for the previous replies.

 

PA, this is for a customer?
"Running" this kind of system is definitely not a spectator sport and I'd make sure she is up to speed on her participation that will be required. It's very cool if you're into it and I wouldn't discourage anyone whose expectations are real. There's definitely an operational learning curve to them and keeping a woodstove running is
Imho not even close.
Again, as long as she is aware, she'll love it to , suprises suck especially when spending this amount.

 

It's one of those special customers you get dragged into now and then.
She has experience keeping 2 wood stoves going inside the house and wants to burn less wood outside the house.
Not sure if this part helps or not, she is a rocket scientist.
She has managed to help keep the astronauts on the space station alive and healthy, so hopefully she can learn to run a wood boiler.

 

If you have the flexibility, they'll throw a lot of heat off the boiler, piping and flue, placement where that heat will go to good use (and not near a t-stat) should be considered.

 

Boiler and storage will be in a insulated pole barn.