Wood fuel quality and energy value

[WFWales]

some of the best info i think I have seen regarding details of firewood as a fuel - http://www.biomassenergycentre.org.uk/pls/portal/docs/PAGE/RESOURCES/REF_LIB_RES/PUBLICATIONS/FC-BEC-INFOSHEET-WOOD-AS-FUEL-TECHSUPP.PDF

 

Any thoughts on the SBAS quality scheme?

[TimberCutterDartmoor]

Shows how little much I know about wood! I was actually taught and have the book somewhere that says hardwood has 1/3 more CV than softwood!

 

Edit: But then I read a little further and it states "per volume". Lol.

Edited January 12, 2011 by TimberCutterDartmoor

[TimberCutterDartmoor]

And here is one of those said documents!

wood-burning.pdf

[WFWales]

25 years is a long time, but I'm still supprised that they got it fundermentally wrong as you say Timbercutterdartmoor...

...assuming they've got it right now of course!!

[truck]

Makes interesting reading....Here's an Excel forestry commision calculator for you to mess about with too.

 

 

 

http://www.forestry.gov.uk/pdf/eng-see-how-many-buildings.xls/$FILE/eng-see-how-many-buildings.xls

[mattplace]

Thats interesting!

 

Does anyone know the weights of seasoned wood (∼20% MC)?

 

Larch has the highest calorific value on their table but seasoned it will be less dense than, say, Ash. But by how much?

 

What i'm thinking is if i sell Larch at 20% less £ per M³ than Ash then the customer will be saving money, but how quickly are they going to burn it compared to Ash?

 

E.g. If the seasoned density of Larch is 20% less than Ash, but the calorific value is higher, then the customer is £'s better off, and ℃'s better off, and happy! And my profit margin is higher because Larch is alot cheaper at the roadside!

 

Can you see my way of thinking?

 

 

(i confused myself when writing this so i hope it makes sense! )

[WFWales]

Cool, I like that spreadsheet....

[WFWales]

Thats interesting!

 

Does anyone know the weights of seasoned wood (∼20% MC)?

 

Larch has the highest calorific value on their table but seasoned it will be less dense than, say, Ash. But by how much?

 

What i'm thinking is if i sell Larch at 20% less £ per M³ than Ash then the customer will be saving money, but how quickly are they going to burn it compared to Ash?

 

E.g. If the seasoned density of Larch is 20% less than Ash, but the calorific value is higher, then the customer is £'s better off, and ℃'s better off, and happy! And my profit margin is higher because Larch is alot cheaper at the roadside!

 

Can you see my way of thinking?

 

 

(i confused myself when writing this so i hope it makes sense! )

 

I know what you mean but it's a bit of a head bender.

 

I estimate that the difference in heat at 0% m/c between ash and larch is about 6%, but I cant get further than that....

...however this leaflet has some basic destinctions of energy value by volume for hard and soft woods, ....you may be able to figure something??

 

http://www.woodfuelwales.org.uk/lluniau/firewood__working_out_the_cost_1.jpg

http://www.woodfuelwales.org.uk/lluniau/firewood__working_out_the_cost_2.jpg

 

good luck!

[mattplace]

Thanks for the woodfuelwales links. They slightly contradict what the Forestry Commission state for calorific value but using their formulas and the FC figures, and alot of head scratching i came up with the following:

 

(These are all example figures for costings)

 

If you sold 1 M³ of Ash for £100 (seasoned to 20%MC) and you were to offer your customers 1 M³ of Larch for £80 (@ 20%MC) then they would recieve the following:

Ash= 7.37 pence/KWh

Larch= 10.32 pence/KWh

(the above is based on 100% efficiency not the appliance efficiency)

 

So the customer is still better off with Ash. You would have to sell the Larch for £57.14 M³ to make it comparable to Ash!

 

I have been offered some Larch cheap so i will be giving it a go for next winter but it won't be 43% less than my hardwood prices! The way i see it, there isn't enough hardwoods to support the rate of demand so customers will have to use softwoods soon. Especially with Phytophthora ramorum, there is going to be an abbundance of Larch in my area!

[TimberCutterDartmoor]

I also find the list of species limited - what about Beech for instance?