THEME FIREWOOD
Mechanisation of Harvesting and Production of Firewood Christophe Barel – ADEME Angers
The CTBA and the IDF have studied various scenarios of harvesting and processing of firewood to estimate production costs per cubic metre or “stere”. The summary of the results of this study ordered by ADEME is now available.
THE VARIOUS SCENARIOS
MEANS FOR PROFESSIONALISING THE MARKET Preserving, or even developing the use of wood logs as fuel requires that the following three points be satisfied: - Efficient heating equipment available on the market; - A fuel with well-known and guaranteed quantity and performance; - A competitive price compared with other sources of energy. To achieve these three conditions, Figure 1: Summary of the Various Scenarios (Ademe - CTBA)
Sc n°1 Sc n°1 bis Sc n°2
Harvesting man.
X X X
Sc n°4
X
Sc n°6
Wood in 2 to 4 m length or more
X
WOOD ENERGY N°7 < DECEMBER 2002 > 12
Agricultural Forwarder tractor
transport processing Semi-trailer
man.
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X
X
X
X
X
X
mecan.
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X
X
X
X
X
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Sc n°7
Traditionally, firewood is harvested in the forest by means of a chain saw, in logs of one metre in length; this allows limiting the necessary investments to the strict minimum because the pieces of wood can be manipulated by hand. The experience acquired in the timber industry sector shows that increases in productivity come mainly from two sources: the mechanisation of timber harvesting and the transfer of work stages from the forest to fixed installations.
skidding mecan.
X Wood in 1m length
Sc n°3 Sc n°5
banding
The use of firewood processors on site enables the processing of full lengths.
ADEME - CTBA
The use of a banding frame makes handling easier for loading and transport.
ADEME has set up the Flamme Verte quality charter (see Wood Energy 5), which displays the most powerful heating equipment, and the "NF firewood" certification (see page 26) that guarantees the characteristics of the fuel. ADEME also asked the CTBA and the IDF to estimate if it was worthwhile mechanising the production of firewood.
INNOVATIONS & PAYSAGES
France
1. Mechanisation of Timber Harvesting • The easiest stage to mechanise is the skidding stage. The skidding of logs of one metre in length is not a very productive operation because these elements are difficult to manipulate with the grabs of tractors or lorries. This is why the loading is mostly done manually; the working conditions are hard and the costs are high. Productivity can be improved by two different means. The first consists in making bundles of 0,5 to 1 m 3 or “stere” by means of stacking frames. The second consists in harvesting the wood in length of two metres or more. In both cases, the handling times are greatly reduced by using a grab. • A second stage of the mechanisation of timber harvesting consists in
abandoning the chain saw in favour of mechanised harvest equipment (harvester). 2. Transfer of Work stages from the Forest to Fixed Installations. This concerns all the phases of manual logging in forests that can be transferred to fixed installations on a site. The combination of these two principles allows identifying the following scenarios. • Scenarios that Preser ve Harvesting of Logs of 1 m in Length - Scenarios 1 and 1b: traditional methods, n°1 corresponds to har-
THEME FIREWOOD
50 45
labour functioning amortization
40 35 30 25 20 15
ADEME - CTBA
10 5
sc n
sc n° 7
°6
°5 sc n
sc n
°4
°3 sc n
°2 sc n
sc n
sc n
Figure 2: Cost of the Various Harvesting Scenarios
This study shows that it is indispensable to increase productivity during the harvesting and the processing of firewood. Abandoning harvesting logs of one metre in length for the benefit of the logs 2-4 m or more in
capacity of the company. Using a harvesting machine can also contribute towards improvement. Mechanisation will however raise two questions: What to do with the
ADEME - CTBA
• Scenarios that Give up the Harvesting of Logs of 1 m in Length Considering the weight of the pieces of wood, these scenarios imply mechanised processing on a site. - Scenario 4: trees are harvested with a chain saw, in logs of two to four metres in length; they are skidded with a tractor and timber trailer equipped with a grab crane; logs are processed on a mechanised specialised site. This way, the productivity of skidding, transport and processing is improved. - Scenario 5: harvesting of the trees with a harvesting machine. All the work stages are mechanised. - Scenario 6: stems are harvested long; they are skidded by means of a tractor with a lifting grab; processing takes place on a mechanised site. - Scenario 7: trees are harvested with a harvester. All the work stages are mechanised.
°1 bis
0 °1
vesting poles from coppice wood or small logs and n°1b to making firewood from tree crowns. - Scenario 2: putting logs of 1 m in length into "bundles", which allows improving the efficiency of skidding and transport. Decreasing the cost does not require a high investment. The weight of logs allows manual stacking. On the other hand, putting logs in “bundles” is tiring and requires a lot of time. - Scenario 3: traditional timber harvesting (logs of one metre in length) and processing on a mechanised site.
cost per stere m3 (€/stere)
RESULTS OF THE STUDY
The use of hydraulic multi-splitters avoids extra handling.
Evaluation of the various stages of production and processing makes possible an estimation of the cost of the various harvesting scenarios. Figure 2 shows that using a frame for making bundles of firewood allows about a 10% decrease in the harvesting costs. The additional investment is small. Harvesting in long pieces and processing on site reduces these production costs by another 25%, but the level of investment is high. The use of harvesting machines (feller/logging machine), where it is possible, contributes to reducing the harvesting costs. Not only is the level of investment high but also volumes become significant, therefore the conditions for introduction of such machines into the market must first be studied closely.
length seems the easiest means for success. The improvement in productivity results from the use of a frame or a mechanised processing installation, a choice will depend on the financing
broadleaf tree crowns that cannot be harvested easily with existing machines? How to avoid the wood delivered to the end user being too wet? The drying of wood before cutting it into sections and splitting
Figure 3: Synthesis of the Results. (Ademe - CTBA)
Production cost
Energy consumption
Harvesting pieces of 1 m in length and using a stacking frame Harvesting longer pieces and processing on a mechanised site
37 €/st
37 kWh/st
28 €/st
54 kWh/st
Timber harvesting with a harvester
21 €/st
60 kWh/st
ATTENTION: These costs include neither the purchase price of the wood, nor the price of the delivery to the end user, nor the infrastructure and prospecting expenses.
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THEME FIREWOOD
The following table shows the detailed calculation of the firewood production costs, with the comparison of different machines manufactured by Pezzolato, and for different annual production cases in steres.
is practically non-existent. Besides, the implementation of mechanised methods will require important investments on behalf of the producers of firewood and it will be advisable to study its profitability for each case separately.
To help the producers who might be interested, a computer program working in Excel, "Eval coût.xls", is a v a i l a b l e o n t h e We b s i t e o f Ademe. 5 <www.ademe.fr/collectivites/ bois-energie/docs/evalco.xls>
COST OF THE EXPLOITATION OF THE FIREWOOD MACH Leasing coefficient over 5 years: 1,932; 290 Eur/month for 100 000 to finance A
Hourly cost = 18922 Eur for 1645 hours/year or: 11,50 E
B
C D E F G H I Purchasing Leasing repayment Lump sum cost case 1 Estimate Standard Cos N° of case Annual of the cost over 5 years sharpening TLC/TLA maintenance on TLC/TLA and Type of production equipment Machine in steres (Estimate) Per year Per stere Per year Per stere Per year Per stere Pe Case n°1, below traditional 'circular saw/splitter' (+ tractor). We have taken into account as expenses the legal allowance for woodm 1974 10 512 Eur 2 437 Eur 1,23 Eur 3 168,94 Eur 1,61 ¢Eur These boxes do not concern Case n°1 2 000 16 639 Eur 3 858 Eur 1,93 Eur 180,21 Eur 9,01 ¢Eur 225 Eur 11,3 ¢Eur 6 Case n°2 3 000 16 639 Eur 3 858 Eur 1,29 Eur 270,31 Eur 9,01 ¢Eur 300 Eur 10,1 ¢Eur 1 0 TLC 750 4 000 20 273 Eur 4 700 Eur 1,17 Eur 360,41 Eur 9,01 ¢Eur 375 Eur 9,5 ¢Eur 1 4 3 000 37 543 Eur 8 704 Eur 2,90 Eur 270,31 Eur 9,01 ¢Eur 285 Eur 9,5 ¢Eur 1 6 Case n°3 4 000 51 059 Eur 11 837 Eur 2,96 Eur 360,41 Eur 9,01 ¢Eur 375 Eur 9,5 ¢Eur 2 TLC 800 6 000 55 564 Eur 12 882 Eur 2,15 Eur 510,59 Eur 8,56 ¢Eur 526 Eur 8,7 ¢Eur 2 4 TLC 900 8 800 60 069 Eur 13 926 Eur 1,58 Eur 690,79 Eur 7,81 ¢Eur 676 Eur 7,7 ¢Eur 2 7 TLC 1000 10 000 67 578 Eur 15 667 Eur 1,57 Eur 780,90 Eur 7,81 ¢Eur 751 Eur 7,5 ¢Eur 3 0 12 000 99 114 Eur 22 979 Eur 1,91 Eur 916,05 Eur 7,66 ¢Eur 901 Eur 7,5 ¢Eur 3 3 Case n°4 15 000 100 616 Eur 23 327 Eur 1,56 Eur 1 156,33 Eur 7,66 ¢Eur 1 126 Eur 7,5 ¢Eur 3 8 TLA 1000 18 000 105 121 Eur 24 371 Eur 1,35 Eur 1 396,61 Eur 7,81 ¢Eur 1 352 Eur 7,5 ¢Eur 4 2 TLA 1200 19 740 108 124 Eur 25 068 Eur 1,27 Eur 1 531,76 Eur 7,81 ¢Eur 1 502 Eur 7,7 ¢Eur 4 6 TLA 1400 26 400 195 225 Eur 45 261 Eur 1,71 Eur 1 847,12 Eur 7,06 ¢Eur 1 952 Eur 7,4 ¢Eur 5 4
EXPLICATION OF THE FIGURES INDICA
A
B C D/E F/G H/I J/K L/M N O P/Q R
case n°1:Circular saw+Splitter+Secondhand Tractor case n°2: TLC 750 with (or without) mechanis. case n°3: TLC 1000 with mechanis. case n°4: TLA mechanised at 100%
Base: one person compensated at 1,61 Eur per stere for his expenses Base: one person using the machine + one helper, or 2 persons: wood Base: two persons that work together - Example 6000 steres cut / sp Base: two persons that work together - Example 19740 steres cut / s
Base of production withheld on 1 year = intake of undressed wood on the ground (cases 1 and 2 for 2 and 3000 steres/year) or on mechanise Purchase value that served in reaching the result box "R" Example: case n°1 = Circular saw + 1 Splitter + 1 secondhand tractor … = 10 51 LEASING UNIMAT / CAM value at 01/11/2001 - One must allow for a back-buying value of 1% at the end of the contract: For case n°1, we mad Sharpening and possible maintenance (planishing / tightening of the blade): TLC 750 = 1 sharpening for 600 st -TLC/TLA 1000 or 1200 for 100 Estimated cost of machine maintenance (oil filter - oil - possible repair costs of breakdowns…) Estimated cost according to power / energy but after various controls on the existing installations The same calculation as above for a carbide blade that will need some tip replacements during its lifetime. The body of the blade almost nev For the TLC or TLA we count 2 persons. Of course, these models can also be used by one person alone: Coefficient = about 0,6 probable… Base 35 hours/week in a year = 1645 hours. With only 1 operator, the productivity would be around 0,6. Ex: 1 person on TLC 1000= 7,3 X 0,6 Based on an annual salary of 18 922 Eur including employee and employer contributions, including holidays, etc. Result in euros and per type of equipment exclusive of transporting wood in 2/3/4 or even 6 metres/ collection and delivery as logs. Only the
IMPORTANT! This document is the property of GF SERVICES. Any reproduction without their WRITTEN authorisation is strictly FORBI E-Mail: info@gfservices.fr Site: http://www.gfservices.fr Nota: This information does not commit GF SERVICES to anything - The inf
WOOD ENERGY N°7 < DECEMBER 2002 > 14
THEME FIREWOOD
TO OBTAIN THE COMPLETE STUDY, PLEASE CONTACT: Jean-Louis Bonnet CTBA
10 avenue Saint Mandé 75012 Paris France Phone: +33 1 40 19 49 19 Fax: +33 1 43 40 85 65
HINES GF SERVICES / PEZZOLATO (Table in Euros)
Eur (35 hours/week) J
K
Follow the explanations column by column in the BOTTOM OF THE TABLE L
M
st according to models Re-tipping of carbide d production = EDF blade
er year Per stere Per year Per stere men, 1,61 Eur per stere, at 1/09/01 the case n°1(see box G) 646 Eur 32,3 ¢Eur 99 Eur 5,0 ¢Eur 021 Eur 34,1 ¢Eur 148 Eur 5,0 ¢Eur 472 Eur 36,8 ¢Eur 197 Eur 5,0 ¢Eur 622 Eur 54,1 ¢Eur 148 Eur 5,0 ¢Eur 162 Eur 54,1 ¢Eur 197 Eur 5,0 ¢Eur 463 Eur 41,0 ¢Eur 394 Eur 6,6 ¢Eur 763 Eur 31,4 ¢Eur 591 Eur 6,8 ¢Eur 064 Eur 30,6 ¢Eur 690 Eur 6,9 ¢Eur 364 Eur 28,1 ¢Eur 827 Eur 6,9 ¢Eur 814 Eur 25,4 ¢Eur 1 034 Eur 6,9 ¢Eur 280 Eur 23,7 ¢Eur 1 241 Eur 6,9 ¢Eur 655 Eur 23,6 ¢Eur 1 773 Eur 9,0 ¢Eur 406 Eur 20,4 ¢Eur 1 877 Eur 7,1 ¢Eur
N
O
P
Q
R
Hourly production, 2 persons
Nr working hours per year
Annual salary cost
Salary cost per stere
Harvesting cost per stere
1,2 (1pers.) 3,6 3,6 4 5,3 7 7,1 7,2 7,3 10,1 10,2 11,8 12 15 (1pers.)
1645 1111 1667 2000 1132 1143 1690 2444 2740 2376 2941 3051 3290 1760
18 922 Eur 12 781 Eur 19 171 Eur 23 005 Eur 13 022 Eur 13 146 Eur 19 441 Eur 28 117 Eur 31 514 Eur 27 333 Eur 33 831 Eur 35 093 Eur 37 844 Eur 20 245 Eur
9,59 Eur 6,39 Eur 6,39 Eur 5,75 Eur 4,34 Eur 3,29 Eur 3,24 Eur 3,20 Eur 3,15 Eur 2,28 Eur 2,26 Eur 1,95 Eur 1,92 Eur 0,77 Eur
12,43 Eur 8,48 Eur 7,83 Eur 7,07 Eur 7,39 Eur 6,39 Eur 5,54 Eur 4,92 Eur 4,86 Eur 4,34 Eur 3,95 Eur 3,45 Eur 3,35 Eur 2,63 Eur
ATED IN THE VERTICAL COLUMNS
s of using a circular saw (total allowance) d taken from a pile or by using a simple log processor lit / loaded in 1690 h (total for the 2) paid 11,5 Eur / hour (see N/O/P/Q) plit / loaded in 3290 h (total for the 2) paid 11,5 Eur /hour (see N/O/P/Q)
d lines 2 Eur - It's not expensive! de the same calculations - 100 000 Frs = 1920 Frs of monthly rent. 00 st. - For case n°1: Legal allowance for the use of circular saw granted to woodmen.
ver wears out so the tips can be replaced many times. = 4,38 st./h: you would have to pay 2283 hours… cost of production figures here.
DDEN. GF SERVICES - 352 Rue Victor HUGO - 42120 COMMELLE VERNAY - Phone: 04-77-67-18-70 Fax: 04-77-67-29-94 formation is given as an indication and can change as the equipment prices and maintenance costs vary.
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