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I have a fair amount of 15yr old Lodgepole that I used to nurse a broadleaf woodland that are now shading them out.

 

I thought I could go for the RHI and install a boiler at the Farm and use the Pine to fuel it. I was thinking about clearing a few acres at a time and leave them on the ground until the needles had dropped, then go out to hill and wholetree chip them when the moisture was right, and fill an adapted sileage trailer to cart them back to the shed to store.

 

We use about 4/5000 litres of oil currently and I am told that 1000litres of oil=15m3 of chipped softwood, would that still be true for Lodgepole does anyone know, as I assume the calorific values and volumes will change using this wood.

 

Question is.. Is there a chipper on the market that would provide a decent quality chip doing whole trees this way and is my initial idea actually going to work!

 

If anyone has any pointers good or bad please let me know

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Here you go...

 

Heating oil is about 40MJ per litre, so 1000 litres = 40GJ, or 11,100 kWh.

 

Your 5000 litres per year is therefore 55,500 kWh.

 

Dry softwood is about 400kg per m3 and has a CV of 18.5 MJ per kilo (5.1 kWh per kilo). i.e. each cubic metre is just over 2000kWh.

 

To replace the oil you will therefore need about 28 cubic metres of chip, if my calculations are correct!

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Here you go...

 

Heating oil is about 40MJ per litre, so 1000 litres = 40GJ, or 11,100 kWh.

 

Your 5000 litres per year is therefore 55,500 kWh.

 

Dry softwood is about 400kg per m3 and has a CV of 18.5 MJ per kilo (5.1 kWh per kilo). i.e. each cubic metre is just over 2000kWh.

 

To replace the oil you will therefore need about 28 cubic metres of chip, if my calculations are correct!

 

Nowadays I try and stick with kWhr all the way but your figures look well within the ball park. Actually on a mass for mass basis softwoods are higher cv than hardwood (because of higher lignin content). We imported softwood pellets that were over 20MJ/kg even with 10% moisture, they were douglas fir I think. whole tree chips will be lower.

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I thought I could go for the RHI and install a boiler at the Farm and use the Pine to fuel it. I was thinking about clearing a few acres at a time and leave them on the ground until the needles had dropped, then go out to hill and wholetree chip them when the moisture was right, and fill an adapted sileage trailer to cart them back to the shed to store.

 

 

This is known as sour felling, allowing transpiration to continue and remove moisture. Will the needles drop off? I've not noticed a lot of needle dropping off lop and top after a thinning, at least not in a season. I suppose you intend just motor manual felling and chipping? Stuff dries much better if harvested with a machine set so it takes strips out of the bark and then it can be stored near point of use, seasoning. Small pine doesn't season well in its bark.

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I know in the past as in the early years we used to harvest the bonnier ones for xmas trees and anything that the gang missed had the needles missing by the following year as you would come across them through the blocks. I guess the knack is getting into the forest when the moisture is right and before they would start to rot. Problem I see is the side sitting in the heather would be damp and the upper side that suffers the exposure may be past it, hence the question about the chipper as I didnt want to spend all winter untangling the stuff out of the auger and then finding a boiler that could cope with the variables of the stuff. Volume is not a problem here, it is just getting it to work!

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I know in the past as in the early years we used to harvest the bonnier ones for xmas trees and anything that the gang missed had the needles missing by the following year as you would come across them through the blocks.

 

but I'll bet by then the wood had already noticeably deteriorated

 

 

I guess the knack is getting into the forest when the moisture is right and before they would start to rot. Problem I see is the side sitting in the heather would be damp and the upper side that suffers the exposure may be past it, hence the question about the chipper as I didnt want to spend all winter untangling the stuff out of the auger and then finding a boiler that could cope with the variables of the stuff. Volume is not a problem here, it is just getting it to work!

 

I guessed volume wasn't a consideration, so the extra 25% or so from the branches isn't much value. Are the trees up to above 0.05m3 to 50mm top? When I did pine thinnings for psr in the 80s i'd managed to fell and sned about 150 poles/day in these sizes of pine first thinnings but I think the trees were 20 years old and that was 600 miles south of you. Lodgepole pine is probably a nightmare to sned in comparison to scots.

 

How do your costs compare between whole tree chipping at stump and shortwood harvesting to yard then chipping?

 

BTW in djbobbins original calc of 28m3 of wood chipped that would make an awkward heap of 80m3. Stacked as poles it only occupies 40m3.

 

Removing the bark at harvest retains more minerals on the land and reduces ash from the boiler.

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My friend supplies woodchip and buys timber in which is then stacked on bearers to keep it off the ground. He usually has to leave it for 12 months to dry out to a suitable moisture content and then hires in a chipper for the day. There are many chippers that will process whole trees but they cost the proverbial arm and leg, think £100,000 for one with its own engine rather than pto driven!

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My initial thoughts were to keep the system as simple as possible which in my farming experience means handling a product as least as possible.

 

I liked the wholetree chipping because:

1. It would keep the forest floor tidy as the areas are rented out for deer stalking and for future operations.

2.I would like to replant an ongoing Xmas tree rotation.

3.Some areas might qualify for native restocking grants etc

4.No waste and possibly the return of some fertility in the needle loss

 

The majority of the trees are between 3 and 6" diameter currently, and to brash them for logs would probably need a more than fair share of chainsaw oil and 2 stroke per volume of wood collected and someone that is getting paid from the neck up is always harder to find.

 

I thought (hoped)

 

Trees down

In with chipper when needles dropped

Tractor and winch, tie up a bundle and drag to chipper

Chipper filling trailer

Dozen loads back to farm

Bucket chips into auger bunker

Warm house!

 

Pluses:

 

I have all the tackle and manpower to do it all except the chipper

2 maybe 3 days would see the job done

 

Minuses:

 

Variable fuel in both energy and composition

The need for constant monitoring nearer chipping date, which itself could be different by several months dependant on season.

Getting the chip out of the forest with excisting gear if the chip date constantly falls during winter

 

Has anyone any cheap oil to sell:biggrin:

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