B.4. Aggregated overview and comparison of the various databases
The resulting tables in the formats as described above are presented in Appendix 4. The
first page of this appendix starts with an overview of the 40 (8 tables times 5 databases)
tables. In this section the main outcomes of this overview are presented in an aggregated
form and the most interesting features and differences are explained. It is explicitly not
the aim of this section to present an analysis of what the role of wood energy is in
Europe at present.
The overview is divided into (1) total wood energy use, (2) the wood energy consumption
in the various sectors and (3) the different types of wood that are used.
B.4.1. Aggregated overview of total wood energy use 25
Table 2 shows a selection of the main results of the tables in Appendix 4 in a very
aggregated mode. One has to take care not to draw fast conclusions from the table itself,
because the aggregated mode hides many structural differences between the various
databases. In the text below the table the main figures will be elucidated by highlighting
the main caveats per region. In the footnotes, general characteristics of the various
databases are summarise.
Table 2: Aggregated overview of selected data from the various databases
|
Total amount
of wood energy in database |
Share of wood
energy in 1990 of: |
|
1980
[PJ]a |
1990
[PJ]a |
Annual growthb
[%] |
Total removals
[%] |
Total energy consumption
[%] |
European Union: EU-15 |
FAOc |
342 |
343 |
0.0 |
11 |
0.6 |
UNECE / FAOd |
1,426 |
1,575 |
0.9 |
49 |
2.9 |
Eurostate |
|
1,523 |
|
50 |
2.8 |
IEAf |
160 |
666 |
|
29 |
2.1 |
LBLg |
509 |
654 |
2.3 |
23 |
1.3 |
OECD-non-Europe |
FAOc |
999 |
975 |
- 0.2 |
13 |
0.9 |
UNECE / FAOd |
3,727 |
|
|
|
|
Eurostate |
|
|
|
|
|
IEAf |
340 |
2,686 |
|
36 |
2.9 |
LBLg |
2,475 |
2,556 |
0.3 |
46 |
2.6 |
Europe -non-EU |
FAOc |
346 |
278 |
- 2.0 |
25 |
1.6 |
UNECE / FAOd |
623 |
559 |
- 1.0 |
42 |
3.1 |
Eurostate |
|
|
|
|
|
IEAf |
161 |
449 |
|
40 |
2.6 |
LBLg |
26 |
38 |
3.5 |
31 |
2.6 |
aTo convert from PJ to Mm3, divide by 10.
bAnnual growth has only been calculated for those databases
that comprise roughly the same countries in 1980 and 1990. In many cases it is
questionable whether the annual growth reflects the real growth of wood energy use or the
degree of coverage of the database itself.
cThe main source is the FAO forest product yearbook. Almost all
countries in the world are covered. Data only reflect direct removals from forest with the
explicit purpose of using it for energy [FAO, 1996].
dQuestionnaire replies about 12 countries and estimations of
the secretariat constitute this database. Almost all European countries are included. Both
direct and indirect forest woodfuels (industrial residues and recovered wood) and the wood
derived product black liquor have been included [UNECE, 1996].
eIncludes all EU-15 countries, 13 have been investigated by
detailed country reports, 2 by more aggregated estimations. Beside all kinds of wood fuels
(which form the major part), also agricultural residues are included [Eurostat, 1996].
fMany countries are included. Wood energy was part of a large
coal questionnaire and the quality of the replies is believed not to be very high [Denman,
1996].
gIncludes only 10 OECD countries, of which the data are
directly based on national energy statistics. Wood is considered as one aggregated source
and may for some countries also include other biomass.
European union (15)
- The large difference of about a factor 5 between FAO on one hand and UNECE/FAO and
Eurostat on the other, is mainly caused by the fact that FAO includes only woodfuels that
are directly removed from the forest, while the others include all wood and wood-derived
fuels. This becomes very pronounced when looking at Table 3, where the total wood energy
figures are disaggregated into individual countries. It can be seen there that especially
in countries with much forest industry there is a large difference between FAO and the
UNECE/Eurostat figures.26
- In 1990 LBL and IEA comprise roughly half of the EU countries, but do include the
largest ones (except France in IEA and Austria in LBL).
- The aggregated figures of Eurostat and UNECE are very close for 1990, although these
institutes did clearly no make any direct use of each others figures. Table 3, however,
shows that there are still considerable differences if the databases are compared country
by country. The general trend is that Eurostat figures are higher for the Southern
European countries and Denmark, lower for the new member states and quite comparable for
the other (7) countries. The two differences appear to outweigh each other for a large
extend in the total figure. A possible explanation for the higher Eurostat figures could
be the inclusion of non-woody biomass (e.g. straw in Denmark and other agricultural
residues in South-EU).
Table 3: Total amount of wood energy in database per EU country in 1990
[PJ]
|
|
FAO |
UNECE/FAO |
Eurostat |
IEA |
LBL |
1 |
Belgium |
6 |
14 |
14 |
0 |
|
2 |
Denmark |
5 |
16 |
28 |
14 |
19 |
3 |
France |
107 |
379 |
360 |
|
270 |
4 |
Germany |
45 |
184 |
123 |
94 |
39 |
5 |
Greece |
14 |
15 |
58 |
23 |
|
6 |
Ireland |
1 |
2 |
4 |
|
|
7 |
Italy |
38 |
43 |
131 |
|
3 |
8 |
Luxembourg |
- |
|
1 |
|
|
9 |
Portugal |
6 |
54 |
91 |
47 |
|
10 |
Spain |
22 |
80 |
153 |
|
|
11 |
The Netherlands |
2 |
6 |
15 |
|
|
12 |
United Kingdom |
3 |
8 |
10 |
6 |
- |
|
EU-12 |
247 |
800 |
989 |
185 |
332 |
13 |
Austria |
27 |
132 |
125 |
113 |
|
14 |
Finland |
31 |
220 |
180 |
158 |
123 |
15 |
Sweden |
39 |
334 |
229 |
209 |
199 |
|
New member-states |
96 |
686 |
534 |
481 |
322 |
|
EU-15 |
343 |
1,486 |
1,523 |
666 |
654 |
Only the LBL data show considerable growth of wood energy use between 1980 and 1990
(Table 2). For FAO the aggregated growth figure is stable and UNECE shows a slow
growth in wood energy consumption.
Table A.3.2. on the share of total removals at Eurostat shows that the figures for 1990
are relatively low compared with other years (where they are about 70% on average). Some
countries have a share which is higher than 100%. Again, this may point at the inclusion
of considerable amounts of non-woody biomass (e.g. agricultural residues). For a country
like Italy, the low degree of self-sufficiency in roundwood supplies (about 50%) could
also be an explanation that consumption of wood/wood waste/other solid biomass is larger
than indigenous roundwood removals. Further, there will of course also be inaccuracies in
the FAO roundwood production figures.
OECD-non-Europe
- In comparing the databases for the OECD-non-European countries, one has to realise that
the countries included in this category differ largely. Therefore, also in this case a
disaggregation into individual countries is presented (Table 4).
- The reason that the share in total removals is considerably higher for LBL compared with
IEA (Table 2), despite of its lower absolute amount of energy, is that Canada is
included in IEA and not in LBL. In the IEA database, Canada has a relatively large amount
of total removals but a small share of wood energy use from these removals (about 20%)
which brings the average for the region down.
- The figures for this region are clearly dominated by the USA figures. The estimates for
the USA for LBL and IEA appear to coincide quite well. A reason for this could be that
both are based on official national statistics. The UNECE figure for 1980 was 3,727 which
is significantly higher. According to this database wood energy represents 4.9% of the
total energy consumption and 88% of the total removals in 1980. The difference between FAO
and the others is smaller here as compared with EU countries; the ration here is about 3.
- The presented growth figures are negligible for this region.
Table 4: Total amount of wood energy in database for OECD-non-European
countries in 1990 [PJ]
|
|
FAO |
UNECE/FAO |
Eurostat |
IEA |
LBL |
16 |
Australia |
30 |
|
|
93 |
|
17 |
Canada |
61 |
|
|
354 |
|
18 |
Japan |
3 |
|
|
|
118 |
19 |
New-Zealand |
1 |
|
|
39 |
|
20 |
United-States |
880 |
|
|
2,200 |
2,438 |
|
OECD-non-Europe |
975 |
|
|
2,686 |
2,556 |
European-non-EU countries
- Again, disaggregation into country levels is needed to make good comparison for the
absolute figures for the various databases. This is presented in Table 5. It can be seen
that FAO, UNECE and IEA included largely the same countries. Note that the LBL database
only includes Norway.
- FAO figures are much closer to UNECE here than compared with the other two regions. One
explanation for this is that also UNECE used much estimations for this regions, the
fuelwood part of which was based on the FAO figures. Thus, partly, this is a resemblance
by definition. The countries from which relatively complete replies were received by the
UNECE questionnaires (Czech Republic, Norway, Poland, Switzerland) show much higher values
than FAO (varying between a factor 2 to 6).
- Both UNECE and FAO show a slow decrease in the wood energy use that is included in their
database.
Table 5: Wood energy in the various databases for European-non-EU
countries in 1990 [PJ]
|
|
FAO |
UNECE/FAO |
Eurostat |
IEA |
LBL |
21 |
Albania |
16 |
46 |
|
12 |
|
22 |
Bosnia & Herzegovina |
|
6 |
|
|
|
23 |
Bulgaria |
16 |
19 |
|
15 |
|
24 |
Croatia |
|
7 |
|
|
|
25 |
Cyprus |
0 |
0 |
|
0 |
|
26 |
Czech republic |
18 |
51 |
|
17 |
|
27 |
Estonia |
|
4 |
|
|
|
28 |
FYR Macedonia |
|
15 |
|
|
|
29 |
Hungary |
26 |
27 |
|
12 |
|
30 |
Iceland |
|
|
|
|
|
31 |
Israel |
0 |
0 |
|
|
|
32 |
Latvia |
|
16 |
|
|
|
33 |
Lithuania |
|
12 |
|
5 |
|
34 |
Malta |
|
|
|
|
|
35 |
Norway |
9 |
53 |
|
38 |
38 |
36 |
Poland |
23 |
58 |
|
27 |
|
37 |
Romania |
26 |
39 |
|
40 |
|
38 |
Serbia & Montenegro |
34 |
26 |
|
40 |
|
39 |
Slovakia |
|
6 |
|
|
|
40 |
Slovenia |
|
2 |
|
|
|
41 |
Switzerland |
9 |
30 |
|
20 |
|
42 |
Turkey |
100 |
117 |
|
224 |
|
|
Europe-non-EU |
278 |
535 |
0 |
449 |
38 |
B.4.2 Aggregated overview of wood energy consumption in the
various sectors
Disaggregation into the different wood-energy consuming sectors has been undertaken by
UNECE, Eurostat and LBL. Figure 1 gives an aggregated overview of the results. All data
are for 1990, except for the OECD-non-Europe data, which are for 1980.
The regions presented in this figure with the largest country gaps are :
OECD-non-Europe for UNECE (only USA included), EU for LBL (only 6 countries, including
Sweden, Finland and France), OECD-non-Europe for LBL (only USA and Japan) and
Europe-non-EU for LBL (only Norway!).
In all three databases household consumption in the EU appears to be about 60% of the
total27.
The transformation sector for LBL is zero in all cases because it has simply not been
included in their database (w.r.t. wood at least), since their transformation sector data
do not rely on national statistics, but on IEA figures, which show no sectoral
disaggregation at all for wood.
B.4.3. Aggregated overview of the various types of wood used for
energy
Figure 2 shows which types of wood are used for wood energy in the three regions
according to the databases of UNECE and IEA. Again the OECD-non-European data for UNECE
only comprise the USA and are for 1980 while all others are for 1990. Remarkable is the
extremely high share of black liquor in the USA for the UNECE data. Although it is not
clear whether their 1990 study [UNECE, 1990] uses the same method as the ETTS V study,
part of the explanation could be in the method of converting the energy unit of black
liquor into wood volume equivalents. In the EU, fuelwood directly from forests, appears to
comprise about 40% in the two databases. According to UNECE, for European-non-EU countries
this percentage is significantly higher (>60%).
B.5. Best estimate for wood energy use
In order to construct the analytical part of this report, a best estimate is made for
wood energy use in EU, OECD-non-European countries and Europe-non-EU.
B.5.1. Best estimate for EU
The two most reliable, complete and disaggregated databases for the EU are the UNECE
and Eurostat database. It is preferred however to use one single set of data for the
analysis chapter. Therefore the strong and weaker points of the two databases are weighed
against each other:
Eurostat
Strong points:
- All data are compiled by national expertise centres. No estimates by Eurostat itself are
included.
- The national centres of expertise were able to spend time on collecting data for their
background reports, because they were paid for it under contract by Eurostat.
- The sectoral consumption data of Eurostat fit within the format of the energy balances
as applied by IEA, Eurostat and UNECE.
- The database is based on the sectoral consumption. Especially household wood energy
consumption data are of high quality, because of the specific surveys that were undertaken
for this purpose.
- Eurostat database is improved and updated every year. Timeseries are produced.
Weaker points of the Eurostat database are:
- The database is very aggregated with respect to the various supply sources. There is
only one category of wood/wood waste/other solid waste which for some EU countries is
likely to include a significant amount of agricultural residues.28
- The quality of the data for the new member states is still lower. For Sweden and Austria
only total biomass/waste estimates have been given (also including MSW, anaerobic
fermentation and biofuel production). These new member states are very important with
respect to wood energy. It is clear that this lack in the database will improve in the
future.
- No data prior to 1989 are available.
UNECE
The strong points of the UNECE/FAO database are:
- The database is explicitly focused on wood energy only.
- The database is based on a high level of disaggregation on supply sources; various
different types of wood are distinguished.
- Data are available back to 1980.
- All large wood energy consuming EU countries are included within the nine countries of
which complete questionnaire replies were received.
- There is already about 20 years of experience within UNECE in collecting and
interpreting wood energy data.
Weaker points:
- There are no timeseries. The gap between the data as presented in ETTS V is ten years,
which is very large. It is a pity that the 1985 information from either the questionnaire
or the 1990 study [UNECE, 1990] were not included in the analysis.
- The definitions of the sectors are not completely in accordance with the ISIC standards
and do as such not fit in the standard energy balances.
- Sectoral consumption data are only available for 6 EU member states.
- The secretariat had to make estimations for 6 countries. The estimations by the
secretariat are not always consistent with those made in the original report by Morin.
- - No timeseries are available, because it is believed that the quality of
available data at the national level does not allow for such a detailed assessment.
- The conversion of black liquor is believed to lead to an overestimation of about 25%.
Although the choice for one of the two would provide the most consistent set of data it
is decided to use both databases:
- The overall wood energy consumption (for 1980 and 1990) and the disaggregation into the
various types of fuels will be based on the UNECE data.
- The 1985 UNECE questionnaire data are added.
- For all categories of wood energy, the number of the preceding year is repeated, if for
a certain country data are not available for all three years (but at least for one year).
If there is no data in a preceding year or if only the 1980 figure is known , data of the
following years are repeated.29
- If for the categories "direct woodfuels", "primary residues" and
"black liquor" for a certain country no data were available at all, they were
estimated. The UNECE estimations in their final report [UNECE, 1996] are adapted so that
they are in consistence with the estimations in the original UNECE background report made
by Morin [Morin, 1995]. This implicates the following:
- The "direct woodfuel" figure is estimated by the FAO fuelwood figure [FAO,
1996].
- The "primary residues" figure is estimated on the basis of the relation
that can be observed in look-alike replying countries30
between their primary residue figure and their figure for veneer and sawnwood production
from FAO [FAO, 1996].
- The black liquor figures have been estimated on the basis of the FAO chemical pulp
figures [FAO, 1996], according to the formula used by Morin.31
- If other figures than direct woodfuel, primary residues and black liquor were not
available for a certain country, it has been estimated as 0.
- The sectoral consumption (not in absolute values but in terms of percentages) is based
on the Eurostat database.32
In this way it is believed that the strong points of both databases are combined,
without doing too much concessions to the consistency of the set of data.
The resulting set of data will be further presented in the analysis part of this
report.
B.5.2. Best estimate for OECD-non-European countries
There is a clear lack of reliable data on wood energy from this region. UNECE and
Eurostat, which were the most reliable databases for the EU, did not include this region,
with the exception of the 1980 USA figures in the UNECE database.33
The FAO figures are believed to present huge under-estimations if one considers total
woodfuel use. The two databases left are LBL and IEA. The LBL database is clearly based
directly on national statistics and is therefore believed to be the most reliable of the
two. Therefore we will use the LBL figures for the USA and Japan, and the IEA figures for
Australia, Canada and New-Zealand. Because of the low reliability, no best-estimate for
this region will be presented on disaggregation to sectoral consumption.
B.5.3. Best estimate for Europe-non-EU
Here the UNECE does present data for all countries. However only figures for four
countries of the total of 22 were based on questionnaires. Figures for the other countries
were estimated as described in chapter B.3. Fuelwood was estimated on the basis of the FAO
figures and primary residues on the basis of comparing their production of veneer- and
sawnwood with countries that did reply.
However, since the UNECE appears to be the least unreliable, and the most complete, we
will use this database (with caution) in the analytical part of this report. Again, no
disaggregation into the various consuming sectors will be made here, because of the low
amount and low quality of data.
B.6. Recommendations
The recommendations will be split in two parts. One are general recommendations to the
whole "wood energy statistical society" and the other are specific
recommendations to FAO with respect to the establishment of a world wide database on wood
energy.
B.6.1. General recommendations
Although it is very clear that communication between the various statistical institutes
that deal with wood energy has rapidly increased the last year, an explicit (ad-hoc)
meeting of representatives of all relevant institutes (at least the ones mentioned in this
report) could be very desirable. A possible initiator of such a meeting could be the
already existing inter-secretarial Working Group on Forest Statistics. Though, it is
desirable that the focus will be mainly on wood energy.
In the following some points of attention will be mentioned that could be dealt with
during such a meeting:
- More integral co-operation between all institutes (so not only bilateral agreements)
could lead to:
- - increased consistency between all wood energy databases
- - more efficient use of the limited resources in all institutes
- - higher quality databases by combining expertise on both forestry and energy statistics
- - better availability of country respondents by avoiding that information is asked more
than one time.
- There should be more consistency in definitions with respect to both the fuel types and
the consuming sectors. The highest level of disaggregation of fuel types should preferably
be based on the inherent quality of the fuel (e.g. difference between woodfuels and
wood-derived fuels, such as black liquor). Further disaggregation that fits within such a
basic disaggregation by individual institutes according to specific wishes is then still
possible. Disaggregation into consuming sector should fit within existing energy
statistics and be according to the official ISIC categories.
- The treatment and conversion of units is an important point of attention. The way in
which primary data are converted should be the same at all institutes. Conversion from
volume to energy units needs some basic assumptions, to be agreed upon by all relevant
statistical institutes. The main are the average dry matter density of the wood that is
used and its average moisture content. On the basis of this, conversion factors can be
calculated. It has appeared that presently there is no clearness on what kind of
assumptions are appropriate. It should be realised that huge distortions can occur with
this.34 It may be necessary not to have overall conversion
factors, but to differentiate for regions (e.g. Nordic countries, Central and Southern
Europe) according to the types of trees that are used for fuelwood. In this case
assumptions can be different for different regions, but the method for conversion should
remain the same.
The conversion method to express black liquor into wood volume equivalents should get
special attention.
- The present national respondents should be made aware of available statistical data that
has been prepared for their country on behalf of other statistical institutes. Activities
that enhance this, are going on at IEA at the moment, where one explicitly points the
national respondents (in case the reliability of data is suspected to be too low) at the
existence of the Eurostat country studies. Activities like this could be extended by
Eurostat and IEA with respect to the figures that have been compiled by the respondents of
the ETTS V questionnaire of UNECE (and vice versa, of course).
- A discussion could be undertaken on the most suitable ways of data collection on the
item of wood energy. Experiences at FAO and IEA have learnt that including wood energy
within a huge questionnaires on other items (respectively the forestry and coal
questionnaire) may lead to neglecting this item. The results of the databases of Eurostat
and UNECE, however, states that energy from wood is a very, but complicated energy source
and therefore deserves more attention.
B.6.2. Recommendations to FAO
The present way in which wood energy is dealt with in forestry statistics seems quite
undesirable. At least, the definition of fuelwood within the present forest product
yearbook should be more clear. If one aims at including direct removals of wood for energy
in order to complete the balance it should be very clear from the name and the definition
of this wood that this is not representative for the total use of wood for energy. The
present name of "fuelwood" and the lack of a suitable definition in the yearbook
does not meet this requirement. An alternative name and definition could be the one that
has been used in this report: "direct forest-woodfuel" (see Appendix 3).
If FAO aims at having a complete database on energy from wood, the present statistical
database should be extended. Of course, this should always be in line (w.r.t. definitions
and units) with existing databases and it should be avoided that questionnaires ask for
information which is already asked for at other places.
One should consider whether it is necessary to collect additional data at member
countries or to make use (possibly in co-operation) of already existing sources. It can be
questioned whether inclusion into the present forestry statistics will guarantee
sufficient attention to this complicated matter of energy from wood.
Inclusion of a complete database on wood energy may not fit within the present structure
of the FAO forestry statistics. The main balance here is in the total removals, while wood
energy is created to a large extend downstream, from sources that have been put in the
production statistics under other categories (like pulp- or sawnwood). Of course, double
counting should be avoided. Either the indirect wood energy use should be a separate item
outside the removal balance or the balance should be constructed as a complete material
flow balance. The latter has the main problem of data-availability and the time-aspect.
This time aspect (wood can be available for energy as a recycled product many years after
its harvest) is a major complication as compared with the balance within energy
statistics.
It is up to the FAO to decide to what level of detail data on energy from indirect
woodfuels and wood derived fuels have to be integrated within the present forestry
statistics.
_______________
25 On the basis of this
section one best estimation for the wood energy use will be constructed, which will be the
basis for the analytical part of this report.
26 For Sweden the difference is a factor 9 and for
Finland a factor 7. If one considers pulpwood, a large part (about 50%) of the wood goes
into energy via black liquor. This is a very important component in Sweden for instance.
27 For the 6 countries examined by LBL 70% of the
household consumption comes from France (where its the only sector consuming wood
according to this database). A similar thing can be observed for Turkey in the UNECE
database. Wood is totally consumed by households and the Turkish household sector
comprises 40% of the Europe-non-EU household consumption.
28 The main reason for this assumption are the very
high wood energy/total removal ratios, which are for some countries well above 100%.
However, beside the inclusion of agricultural residues there could also be other reasons
for this high figure, like: (i) dependency of the country under consideration on imports
of roundwood which are indirectly used for energy, (ii) inaccuracies in the FAO roundwood
production figures.
29 With Arecovered products@ we did not use this
backward repetition. If data on previous years were not known for this woodfuel type, they
were estimated as 0.
30 The figures for the non-replying countries
Belgium/Luxembourg, Greece, Ireland, Italy, Portugal and United Kingdom were based on the
replying countries Denmark, France, Germany, Spain and the Netherlands.
31 This means that the number of tonnes of chemical
pulp is divided by 0.44 to get to the wood equivalent of black liquor in cubic meters. For
the 1980 figures the 1982 chemical pulp figures were used, because the 1980 figures were
not available.
32 An exception is made for Sweden and Austria, for
the sectoral consumption data are available in the UNECE database and not in the Eurostat
database.
33 The 1990 report of UNECE [UNECE, 1990 #20] did also
include figures for the USA for 1985.
34 For instance: the lower heating value of wood on
wet weight basis is about 14 MJ/kg for wood of 20% moisture content (which is air dry in
some areas) and 8.0 MJ/kg at 50% moisture content (fresh wood in most areas). If addition
to the assumption of the moisture content, the ratio between coniferous and non-coniferous
wood is assumed differently (the dry matter density can vary by at least 20% on average),
a difference of the lower heating value per (wet) cubic meter of a factor 2 can occur.
B.7. References
Broek, 1996: Review on data on woodfuel use, production and trade in European
countries: a preparatory document for the regional "Wood energy today for
tomorrow" study on European countries., Department of Science, Technology and
Society, Utrecht University, Utrecht.
Chipeta, M., 1996: Personal communication, FAO, Rome, 1996.
Denman, J., 1996: Personal communication, IEA, Paris, 1996.
Eurostat, 1993: Energy consumption in households, , Luxembourg.
Eurostat, 1995: Renewable energy sources statistics: 1989-91, , Luxembourg.
Eurostat, 1996: Renewable energy sources statistics: 1989-1994, , Luxembourg.
FAO, 1996: FAO forest product yearbook, , Rome.
IEA, 1996a: Energy balances of OECD countries: 1993-1994, IEA, Paris.
IEA, 1996b: Energy statistics of OECD countries: 1993-1994, IEA, Paris.
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