The efficiency of kiln drying firewood?

[Justme]

Again true but I doubt most firewood burnt is near 20%. So still about how much heat you actually gain.

[scbk]

I heard from someone about a local "big house" type place that buys in 5 artic loads. I think the first 2 loads are used to dry the remaining 3, which are then burnt to heat the buildings etc

[scbk]

2 hours ago, Big J said:

Had I been in the position at the time to take advantage of the proposterous amount of money the government were offering at the time, I'd have done the same.

It's not the government's money, it's everyone else that's paying for it through their bills, including the little old lady who can't afford to put the heating on.

[Big J]

3 minutes ago, scbk said:

It's not the government's money, it's everyone else that's paying for it through their bills, including the little old lady who can't afford to put the heating on.

Very true. It is however the government that offers it out, and the government that imprisons us if we don't pay it as part of our taxes.

 

As a point aside, does anyone know of any other countries where the government offers such generous payments for burning timber to dry timber for burning, which is often used to dry timber to be used for burning, which is often....... you get the idea.

[spuddog0507]

1 hour ago, Big J said:

We had 26 days of rain last month - my washing line has been as much use as a chocolate fireguard this winter!

you would get a lot better rinse thou,,,,

[Peasgood]

1 hour ago, Big J said:

We had 26 days of rain last month - my washing line has been as much use as a chocolate fireguard this winter!

Put it in a shed or poly tunnel then. Works the same as with logs. 

[spuddog0507]

the RHI payment has this not come from the European directive ? if so i thought it was for any country with in the European union ! to me its just one big box ticking exercise and how things like this can be cost effective is beyond me, Guy i rent my building off has a boiler that is massive and its linked up to a drying floor that he drys the fibers out of cow shit once it has gone through a press and almost all the liquid squeezed out, takes about 48 hrs to dry 2 silage trailer full, this is then used for cattle bedding, this boiler burns 2+ arctic load of chip a week, now the cost of the chip would buy a awfull lot of cattle bedding but that would not make any money under the RHI payment scheme, as i under stood what he was telling me at Christmas was that the boiler would be paid off in 30 mths and after that it was a win win situation with government payments, !

[SbTVF]

Thanks for that. Your imput is much appreciated! 
 
Do you think that you are gaining an efficiency saving by having the kiln as part of a larger system? You're operating on a roughly 8:1 ratio of timber dried to timber burned, but that's using sub 30% chip, which (if spruce) will be a little over half the weight for it's volume compared to fresh felled. So my notion of 5:1 holds (I think!).

Only in that the system is almost entirely paid for by the savings we make on electricity now. The RHI helps make it more affordable and pays for all the wood to chip but the savings would have paid for the system and installation.

We'd have another without RHI if it dies after the payments stop. Still cheaper than gas or electric heating for the pigs.

I'd say its only 3t of chip per 25t load of hardwood if you apportion it out of the overall usage. We'd never be in a position to turn all the rest of it to use the kiln on its own so I'm not sure how it would affect the usage.

I know in summer that sometimes, the kiln holds and builds so much heat that the water temp going back to the boiler is higher that it came out and overheats the boiler if we're not careful!

[Squaredy]

I agree with you in principal Jonathon, but the biggest difference that kiln drying makes from a business perspective is time and space, which of course equals money.

 

If you are selling £50.000 worth of firewood per year and do not kiln dry you will have to have space to store around 1000 full IBC cages in a well ventilated building, with good access all round so you can get to the oldest ones first.  Plus of course you will need to tie up a lot of capital in logs and processing time, hoping that you will be able to make a profit in two years and more.

 

In principal though I agree it is a shame to force dry when nature will do it for you.  What would solve the problem is if kilns could be made more efficient, and recover their heat.  Most large kilns simply vent their hot air to the atmosphere - just like a tumble drier - such a waste, but we haven't yet invented a practical alternative.  I am aware of heat recovery systems, but they are not really effective as far as I know on the scale we are talking about.  

 

 

[gdh]

I don't agree with the new regulations but I don't see kiln drying as a problem. From a personal point of view there's no way we could do the amount and quality we do consistently without it.

 

Looking at it economically it makes sense as well - using less than 10% of your lowest grade timber is a very good trade off to ensure you never run out, can dry in any conditions and only need a fifth of the storage.

 

Air drying obviously has benefits to, they're just different techniques to get similar results, it depends on the individual business which works best.