Log Gasification wood boilers

teepee

Log gasification wood boilers .Hi , with all this talk of log gasification wood boiler I have a question on fuel supply per year .The manufacturers say that the hopper needs to be fill once every day in mid conditions and in very cold conditions that it needs to be filled twice a day . In summer time that is needs to be filled once every 3 days .So my question is that the manufactures says it needs 15-20 meters cubied per year ofcopped wood @ a moister contain of 15/20% . How can that quantity be right when the hopperis 500*500*700mm equals 0.175m3 per day by 7 days equals 1.225m3 per week .The boiler will be on each day of an average of 35 weeks multiply by 1.225m3 equals 42.87m3 .And in the summer for 17 weeks once every 3 days equals 39 times by 0.175m3 equals 6.82m3 .So winter & summer combined together is 49.69m3 per year . Can anybody see were I am goingwrong as manufactuer recommend 20m3 per year .Also if that’s the case 49.69m3 of timber per year @ 80 Euro per m3 equals 3975.20 Euros .Ok I get the timber for free waste of cuts , but it cant make since to purchase chopped timber .So what do you think .

CJhaughey

You are not filling every single cubic centimetre of the hopper, there would be a fair difference between the capacity and the actual wood inside it.

teepee

Good point , has anybody kept a record of there fuel supply for the year ?

kevymoss

Why not try a chip silo so that you so that you do not need to keep refilling. That estimation of fuel cost is very high¬

10-10-20

I think you've made two incorrect assumptions.
Firstly, as Mr Haughey pointed out, you will not be filling all 0.175cm^3 of the hopper each fill.
I would estimate that you will 60% to 80% fill it, allowing for room at the top and also between the logs. After all, these devices need to circulate gasses between the wood...

Secondly, you are also assuming that you will consume all of the hot water produced by the boiler ever day. I suggest that this is unlikely as there will be some left in the buffer tank at the end of most days. Don't forget that the last thing you want to do is actually run out of hot water as it's not a quick process to heat up another load considering the size of most buffers.