Storage question

[Birdman]

I have a tarm solo 40. If i filled the Tarm with a load of wood( I know.. it varies as to type of wood, moisture etc) but, about how much storage would i need so that if the Tarm went full out for the whole load the storage could take the whole amount of heat. I guess i am looking for the best estimate? 200 gallons? 400 gallons?

 

[chuck172]

I have 500 gallons pressurized. With a full load, my boiler doesn't idle, and I still have to add wood to bring the tank up to 190-195*

 

[stee6043]

I think sizing storage based on boiler output is kind of silly. Sizing it based on load is more appropriate. Anything less than 500 gallons is kind of wasted work based on most accounts. 500-1000-1500 gallons is more usefull and wortwhile if you're going to spend the time and money on plumbing...

 

[sgschwend]

Here is how you calculate the BTUs:

You need to determine the number of BTUs a load of wood will produce, this can be done by looking at tables of heat output versus tree species, adjusting the table value to the number of cubic feet you load into your machine. Reduce the output by the efficiency of your boiler.

You now have the number of BTU available to heat the storage water.

You then need to decide what temperature the water would typically be before you re-heat it, something like 120 F; and you also need to know your storage maximum temperature (180 F). This give you the delta temperature you need to know.

Then it is a simple calculation for the gallons of water needed for the number of BTUs versus the detla T.

It take 8.33 BTUs to raise one gallon of water 1 degree F.

 

[Birdman]

From everything I have read on this site.. I guess it does sound like 500 gallons is the least amount of storage one should really have. However, is there anyone out there that uses less than 500 gallons? If so, how is working out? Do you wish you had gone with more storage? Is it sufficient for your needs? What are the positives and (obvious) negatives of your situation? How long does your storage last? ( real world application).

 

[Birdman]

What are most Europeans doing with storage? Do they use 500-1000 tanks?

 

[oilbegone]

I have used a Solo 30 with a 600 gal STSS tank bought through Tarm for one season and it is working out great. The storage is the most useful at the beginning and end of the heating season and in the summer for hot water. When I installed it the thought of using the wood boiler for hot water in the summer sounded crazy. I could not have been more wrong, it is only my wife and I but I was getting an entire week of hot water out of one burn on Sunday night. Good Luck

 

[taxidermist]

What are most Europeans doing with storage? Do they use 500-1000 tanks?

Most europeans dont live in 2800+sqft houses so I have been told thats why they can get away with smaller storage than we can. For 500 to 1000gal min unless you live somewhere where you have mild winters.

Rob

 

[chuck172]

I think you can get away with less storage and a more overall efficient heating system in general if you install low temp. emitters. That's how Europeons get away with smaller storage tanks.

 

[jebatty]

Smaller storage may serve more as a buffer tank by absorbing peak boiler output not needed by demand, rather than storage intended to supply heat for substantial time periods when the boiler is not firing Also, likely would be most useful/efficient in a system where the boiler is accurately sized to demand.