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Citation: Šafarík, D.; Hlavácková, P.;

Michal, J. Potential of Forest Biomass

Resources for Renewable Energy

Production in the Czech Republic.

Energies 2022, 15, 47. https://

doi.org/10.3390/en15010047

Academic Editor: Javier Fermoso

Received: 25 November 2021

Accepted: 18 December 2021

Published: 22 December 2021

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energies

Article

Potential of Forest Biomass Resources for Renewable EnergyProduction in the Czech Republic

Dalibor Šafarík, Petra Hlavácková * and Jakub Michal

Department of Forest and Wood Products Economics and Policy, Faculty of Forestry and Wood Technology,Mendel University in Brno, Zemedelská 3, 613 00 Brno, Czech Republic; dalibor.safarik@mendelu.cz (D.Š.);jakub.michal@mendelu.cz (J.M.)* Correspondence: petra.hlavackova@mendelu.cz

Abstract: In the European Green Deal and the Climate Act, the European Union has committed itselfto achieving climate neutrality by 2050. This goal is to be achieved by joint efforts of all economicsectors, including forestry and its downstream sectors. One way to attain this goal is the effective andsustainable use of forest biomass for energy production. This article aims to quantify the potentialof forest biomass resources for the production of electrical and thermal energy based on officialdepartmental statistics, the current legal framework for forestry and the environment, and researchresults in the context of an extreme change in the raw material base due to the ongoing calamitycaused by the spread of insect pests in the Czech Republic. This extreme can classify as a significantrisk to the security of the energy supply from renewable sources in the event of oversizing newinstalled energy production from renewable sources. Based on data and calculations, an overallannual volume of dendromass available for energy production in the Czech Republic for the periodextending to 2036 was quantified at the value of 13.473 million tons per year. Consequently, it is clearthat the overall dendromass resources for energy production in the Czech Republic are not sufficientto achieve the EU’s ambitious objective.

Keywords: forest biomass; renewable resources; resource potential; forest policy; Green Deal;Czech Republic

1. Introduction

In March 2020, the European Commission presented the Climate Act [1,2], aiming tomove Europe towards climate neutrality. The objective of this European climate legislationis to put into practice the goal set out in the European Green Deal [3] to make the Europeaneconomy and society climate neutral by 2050 while using resources efficiently and main-taining competitiveness. In October 2020, the European Parliament adopted a mandate tonegotiate a climate law, approving the goal of climate neutrality and reducing emissionsby 50–55% by 2030 compared to 1990 levels. All economic sectors, including forestry andits downstream sectors, should contribute to achieving climate neutrality [1]. One of theways that forestry and forestry-based sectors can help achieve the goal of climate neutralityand thereby fulfill the provisions of point (d)—Trajectory to achieve climate neutrality:Energy efficiency, availability, and security of energy supplies is effective and sustainableconcerning the use of dendromass for energy production.

In December 2018, the Renewable Energy Directive II (RED II) was adopted, whichstipulated the objective of a 32% share of energy from renewable sources by 2030 [4]. Theroadmap for transforming the economy and society of the European Green Deal of 2021 setsa higher goal, namely 40% of energy from renewable sources by 2030. In 2019, the share ofrenewable resources in energy production for EU-28 was 18.88% [5]. In the Czech Republic(CR), this share amounted to 16.24% [5] in 2019, and the objective of achieving a 22% shareof renewable energy sources in gross final consumption by 2030 was set [6]. The questionis whether there are sufficient resources available to meet this objective, considering the

Energies 2022, 15, 47. https://doi.org/10.3390/en15010047 https://www.mdpi.com/journal/energies

Energies 2022, 15, 47 2 of 16

calamity conditions and the developments in felling opportunities in the Czech Republic inthe coming decades.

This article explores the availability of resources and the assurance of the security ofthe dendromass supply for energy production. It specifically deals with quantifying thepotential of forest biomass sources and overall dendromass sources to produce electricaland thermal energy in the Czech Republic. Forest biomass falls within the biomass sourcesthat the European Commission calls unused, i.e., residual biomass [7]. The analysis pro-ceeds due to the fact that biomass (including forest biomass) is a renewable yet limitedresource [8]. As reflected by International Energy Agency [9], renewable energy sources(RES) are currently at the heart of the transition to a less carbon-intensive, sustainableenergy system. The need to maximize the deployment of RES is also mentioned in theCommunication from the Commission to the European Parliament entitled ‘A Clean Planetfor All’ [10]. Biomass is often described as the most important renewable energy sourceglobally [11]. According to Eurostat [12], biomass currently represents 60.5% of the totalshare of RES in primary energy sources. In countries with conditions similar to the CzechRepublic (forest coverage, standing volume), dendromass and forest biomass are seen asthe dominant renewable resource [13]. In the Czech Republic, the current share of all formsof biomass, including biomass from agricultural production, is almost 90% of the total shareof RES in overall energy consumption [13]. In the Czech Republic and Central Europe, theuntapped potential of biomass forms the most important part of the planned developmentof renewable energy sources [14]. The transition to renewable energy sources depends onvarious factors [15]. RES policies are crucial to achieving carbon neutrality [16]. Bioenergy,i.e., renewable energy generated from raw materials of biological origin, has the potential toreduce greenhouse gas emissions since RES produce a negligible amount of carbon duringtheir life cycle [16–18]. Investment in bioenergy plants is usually conditioned by access tothe raw materials as well as the cost of obtaining this raw material [16,19].

Despite widespread global demand, biomass resources are unevenly distributed, withrelatively low resource availability in some of the highest-demand regions [20]. Energysecurity directly affects a country’s level of economy, security, and social well-being [16].As several studies carried out in different EU countries show (see for example [21–24]),there is uncertainty regarding the amount of biomass available in the EU, and currentimport options call into question political goals concerning the security of supply andsustainability. The issue of the potential of supply and availability of renewable energysources, especially forest biomass, is also addressed in studies from outside the EU (asevidenced, for example, by publications [25,26] in Japan, refs. [27,28] in India, refs. [29,30]in China, ref. [20] in Brazil, or [31–33] in Africa.

An overview of the current state of studies dealing with the potential of biomassresources and their types was discussed in the article [11]. The authors conclude thatthere are many studies on the potential of biomass, but their results vary considerably.Moreover, definitions of biomass potential differ, too. For example, ref. [34] distinguishesbetween theoretical, technical, economic, and implementation potential. The article focuseson the technical potential, i.e., the part of the potential that can be utilized using currenttechnical possibilities [11], and describes the possible contribution of forest biomass anddendromass from non-forest land to satisfying energy demand from a technical point ofview depending on time and place. The amount of biomass available for energy productionstrongly depends on the origin of the resource and its alternative uses or restrictions on itsuse [24].

Forests are a significant potential source of biomass, and the Intergovernmental Panelon Climate Change (IPCC) has identified forest biomass as an essential source of renewableenergy [35]. Forest tree biomass (dendromass) mainly includes forest residues, whichthe literature [36] divides into primary residues: (by-products of conventional forestry);secondary residues (by-products of industrial processes); tertiary residues (by-productsof construction, demolition, and packaging processes). Forest residues are considered the

Energies 2022, 15, 47 3 of 16

largest and most important source of dendromass for biofuel production [37] and representan important lignocellulosic raw material for bioenergy production [38].

Within Czech forestry, approximately 0.77 million tons (2 million m3) of wood chipsfrom primary forest residues, 1.5 million tons of cellulose extracts, and less than 5 milliontons (7.5 million m3) of primarily produced fuelwood further used for energy purposesare produced annually [6,39]. In recent decades, massive occurrences of bark beetles (Ips.spp.) have caused a significant decline in coniferous, mostly commercial forests, includingspruce stands on non-forest land in Central Europe, specifically in Germany, Austria,Poland, Slovakia, and especially in the Czech Republic [40,41]. As a result of the barkbeetle calamity, the volume of the forest biomass supply for energy purposes in the CzechRepublic is expected to decrease [41]. Predicting the availability of forest dendromassregarding the further course the bark beetle calamity might take is currently extremelydifficult [6].

This article aims to quantify the potential of forest biomass resources for the productionof electricity and thermal energy based on official departmental statistics, the current legalframework for forestry and the environment, and research results. A factor playing acrucial role in this quantification is the context of an extreme increase in the felling of forestsdue to the ongoing calamity caused by the spread of insect pests in the Czech Republic.

Given the existence of many studies whose results differ significantly, the objectiveis a complex one and requires a comprehensive approach. Some of the reasons for thedifferences in those studies’ results are the inconsistency of the bases from which thepotential of forest biomass resources is derived and the diversity of calculation levels.Therefore, the sub-goals also included unification of the calculation level based primarilyon updated standing wood mass volume, updating the harvesting opportunities in theprimary production, and a projection of risks resulting from the loss of coniferous standsdue to the bark beetle calamity related to secondary production. The resulting values areconverted to a uniform level of mass units. The crucial question is whether the set target ofa 22% share of renewable energy sources in the gross final energy consumption by 2030 canbe achieved in the Czech Republic with the contribution of dendromass and forest biomassand concerns the knowledge of the facts relating to the overall change in the raw materialbase.

2. Materials and Methods2.1. Input Data and Information Source

The research methodology was divided into two stages. The material required forobtaining the relevant outputs for the first part was obtained from the secondary research.It was based on an analysis of the available scientific literature dealing with the issue ofrenewable energy sources, especially forest biomass. Binding documents of the EuropeanUnion and the Czech Republic, the data of official European, national, and departmentalstatistics, and the current legal framework of forestry and the environment at the level ofthe European Union and the Czech Republic, were subjected to a comparative analysis.

In the second stage, the potential of forest biomass resources available for electricaland thermal energy production was quantified in the context of an extreme increase inforest felling caused by the spread of bark beetles in the Czech Republic and a reduction inforest increment.

The analysis of secondary data sources was performed in three parts:

1. Binding documents of the EU and the Czech Republic in the field of RES, which mainlyinclude strategic documents, the Climate Act, and the European Green Deal [1–3],National Renewable Energy Action Plans of European Union’s Members [6,39,42],Clean Planet for All [10], Fit for 55 Package [43], New EU Forest Strategy for 2030 [44],or legislation [4,45–47].

2. Official European, national, and departmental statistics—Eurostat [5], InternationalEnergy Agency [9], Food and Agriculture Organization of the United Nations [48],

Energies 2022, 15, 47 4 of 16

Czech Statistical Office [49], Ministry of Agriculture [50], and Ministry of Industryand Trade [6].

3. Other documents, articles, and studies included in the bibliography.

2.2. Data Analyses

To determine the potential for the energy use of forest biomass from forest stands inthe Czech Republic, the following causal data and information on the state of timber stocksand sources in forest stands were used, on which a comparative analysis was performed:

The theoretical outlook of logging opportunities for the period of 2017–2057 in forestsin the Czech Republic was provided by the Forest Management Institute (FMI) Brandýsnad Labem and prepared based on forest management plans (FMP) and forest manage-ment curricula (FMC) stored in the data storage of the FMI Information, and Data Centreand available FMP and FMC data for the period of 2008–2017. The theoretical fellingopportunities, ref. [51], were derived from the published data concerning standing stockusing standard indexes of normal clearing and felling percentage. In each decennium, theprocedure of felling outlook calculation included the following steps:

1. The regeneration logging volume is determined based on the felling percentage.2. The logging area is determined based on felling percentage.3. If the felling percentage is zero, the thinning volume shall be calculated based on the

thinning percentage.4. The age is increased by ten years.5. The area is decreased by the felling area.6. The first age class is founded with the acreage of the felling area and is included

among the regenerated parts of the stand.7. The stock is decreased by the regeneration felling volume.8. The stock is increased by the increment coefficient derived from these tables:

• Estimate of timber stocks in predominantly coniferous stands undamaged bybark beetle calamity up until September 2019 prepared by the Forest Manage-ment Institute (FMI, March 2020) [52]. Partial outputs from the project “Poten-tial of structural changes in sustainable forestry and wood processing” NAZVQK1820358 solved by the Department of Forest and Wood Products Economicsand Policy of the Faculty of Forestry and Wood Technology, Mendel Universityin Brno in the years 2018–2020. A model of timber flow, ref. [53], between indi-vidual branches of the forestry and timber complex (FTC) was created using themethod of retroactive calculation of the produced volume of products with theapplication of material decay coefficients of the flow of raw materials in primaryprocessing. These coefficients range between 1.07–4.85 m3 (Raw Wood Use/m3

of Product), for example, Impregnation—1.07 m3, Softwood lumber—1.72 m3,Softwood plywood—1.81 m3, and Pulp—4.85 m3. More detailed specifications ofthe method are included in final reports on the research NAZV QK1820358, avail-able at: https://starfos.tacr.cz/cs/project/QK1820358 (accessed on 15 November2021) and publications by authors [54].

3. Results3.1. Theoretical Outlook for Production Possibilities Based on 2017

According to the data contained in the material [51], the structure of the total woodstock in economically usable forest stands in the Czech Republic in 2017 was as follows:

• Removal stands 277.84 mil. m3 of timber to the top of 7 cm outside bark (up to 7 cmo.b.)

• Premature stands 378.53 mil. m3 up to 7 cm o.b.• Total of 656.37 mil. m3 up to 7 cm o.b.

The indicator of annual regeneration felling derived from the normal clearing in2017 was 9.18 million m3 of timber to the top of 7 cm outside bark. The total stock of

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656 million m3 of timber to the top of 7 cm o.b. was valid for the decennium 2017–2026in 2017, i.e., before the massive impact of the bark beetle calamity on the condition andstructure of timber stock in the forest stands in the Czech Republic, and the theoreticalfelling opportunities were derived from it. Figure 1 shows the outlook for forest stockdevelopments over four decennia.

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• Premature stands 378.53 mil. m3 up to 7 cm o.b. • Total of 656.37 mil. m3 up to 7 cm o.b.

The indicator of annual regeneration felling derived from the normal clearing in 2017 was 9.18 million m3 of timber to the top of 7 cm outside bark. The total stock of 656 million m3 of timber to the top of 7 cm o.b. was valid for the decennium 2017–2026 in 2017, i.e., before the massive impact of the bark beetle calamity on the condition and structure of timber stock in the forest stands in the Czech Republic, and the theoretical felling oppor-tunities were derived from it. Figure 1 shows the outlook for forest stock developments over four decennia.

Figure 1. Outlook for the development of wood stocks in forest stands.

The theoretical outlook for decennial felling opportunities calculated from felling percentages is shown in Figure 2. The theoretical outlook of decennial assortment options for the period 2017–2056 is given in Table 1.

Figure 2. Theoretical perspective of felling opportunities in one decade for the period of 2014–2054.

Figure 1. Outlook for the development of wood stocks in forest stands.

The theoretical outlook for decennial felling opportunities calculated from fellingpercentages is shown in Figure 2. The theoretical outlook of decennial assortment optionsfor the period 2017–2056 is given in Table 1.

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• Premature stands 378.53 mil. m3 up to 7 cm o.b. • Total of 656.37 mil. m3 up to 7 cm o.b.

The indicator of annual regeneration felling derived from the normal clearing in 2017 was 9.18 million m3 of timber to the top of 7 cm outside bark. The total stock of 656 million m3 of timber to the top of 7 cm o.b. was valid for the decennium 2017–2026 in 2017, i.e., before the massive impact of the bark beetle calamity on the condition and structure of timber stock in the forest stands in the Czech Republic, and the theoretical felling oppor-tunities were derived from it. Figure 1 shows the outlook for forest stock developments over four decennia.

Figure 1. Outlook for the development of wood stocks in forest stands.

The theoretical outlook for decennial felling opportunities calculated from felling percentages is shown in Figure 2. The theoretical outlook of decennial assortment options for the period 2017–2056 is given in Table 1.

Figure 2. Theoretical perspective of felling opportunities in one decade for the period of 2014–2054.

Figure 2. Theoretical perspective of felling opportunities in one decade for the period of 2014–2054.

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Table 1. Theoretical perspective of the possibilities of production of wood assortments in one decadefor the period 2017–2056 (thousand m3 up to 7 cm o.b.).

Decennium 2017–2026 2027–2036 2037–2046 2047–2056

Roundwood 155.343 113.640 106.025 97.293Pulpwood 29.202 29.195 32.332 33.486Fuelwood 9.769 9.122 10.040 10.127

Total 194.314 151.957 148.397 140.906

The maximum overall annual outlook for felling opportunities derived from the 2017base by individual decades is as follows:

2017–2026: 19,43 mil. m3 up to 7 cm o.b.2027–2036: 15.20 mil. m3 up to 7 cm o.b., a decrease by 21.8% against the 2017 base2037–2046: 14.84 mil. m3 up to 7 cm o.b., a decrease by 23.62% against the 2017 base2047–2056: 14.09 mil. m3 up to 7 cm o.b., a decrease by 27.5% against the 2017 base

In the average assortment structure; saw logs 69–80%, pulpwood for the pulp andpaper industry, production of agglomerated materials 15–24%, firewood 5–7%.

The long-term theoretical annual available volume of lump fuelwood derived from the2017 base, considering a shift of approx. 10% to pulp assortments, amounts to a maximumof 8.78 million m3 of timber to the top of 7 cm o.b. plus approximately 4.5 million m3 oftimber from felling residues and non-forest land (protection zones of product pipelines,corridors of railway transport routes, riparian vegetation, municipal greenery, etc.). Thus, atotal of 13.28 million m3 (8.22 million tons) per year.

3.2. Estimate of Timber Stocks in Mostly Coniferous Stands Undamaged by Bark Beetle Calamityuntil September 2019

As of September 2019, the bellow estimates were obtained [52] based on remote sensingresults, LMS, Sentinel-2, and Planet data:

• area of standing coniferous forests, 1.721 thousand ha• area of felling and dead standing trees for January 2016–September 2018, 106 thousand

ha• area of felling and dead standing trees for September 2018–September 2019, 47 thou-

sand ha

Finally, three basic categories were established for the framework definition of thecategories of spruce stands endangered by bark beetle calamity:

1. up to 500 m above sea level—high-risk stands in which spruce cannot be used eco-nomically in a systematic way are currently already felled, or residues of stands ofsterile dead tree stands remain unfelled

2. above 500 to 800 m above sea level—endangered stands where spruce in living standsis currently still endangered by the impact of bark beetles, especially Ips typographus,L.

3. above 850 m above sea level—less endangered stands; up to 950 m above sea level,spruce can be systematically used as an admixture in normal habitats, in water-affected habitats as a basic tree species; above 950 m above sea level, spruce can besystematically used as a basic tree species.

Estimates of stand areas and total timber stock in selected stands are presented inTable 2.

Energies 2022, 15, 47 7 of 16

Table 2. Estimated stand areas and total wood stocks in predominantly coniferous stands in 2019(million m3 up to 7 cm without bark).

Up to 500 m aboveSea-Level

500–850 m aboveSea-Level

Above 850 m aboveSea-Level Total

Area of predominantlyconiferous stands (ha) 700,702 838,050 182,511 1,721,263

Estimation of Norwayspruce stock in undamaged

stands (million m3 without bark)103.3 ± 11.1 243.4 ± 16.1 54.1 ± 7.6 400.8 ± 15.4

Estimate of stocks of undamagedmostly coniferous stands(million m3 without bark)

197.5 ± 13.9 298.2 ± 17.6 56.2 ± 7.7 552.0 ± 15.4

Estimate of stocks of all treespecies in undamaged mostly

coniferous stands(million m3 without bark)

227.6 ± 15.3 323.9 ± 18.8 60.0 ± 8.1 611.5 ± 16.6

Source: [52].

Based on the total published volume of total felling in 2019 and 2020 in the amount ofapprox. 32.6 million m3 or 35.8 million m3 [49], it can be concluded that:

• the estimated stock of coniferous trees in predominantly coniferous stands as of 31December 2020 was 505.34 ± 15.4 mil. m3 without bark (w.b.) in total; a decrease of8.5% excluding the timber increment,

• the estimated stock of all coniferous trees in predominantly coniferous stands as of 31December 2020 was 564.84 ± 16.6 mil. m3 w.b. in total; a decrease of 7.6% excludingthe timber increment.

• the estimated stock of all coniferous trees in economically exploitable stands in theCzech Republic as of 31 December 2020 amounted to a total of 632.21± 1.09 mil. m3

w.b. including the lower limit of the point estimate of the overall annual increment(24.43 mil. m3 w.b.); a decrease of 3.2%.

3.3. Assumption of Infestation and Felling Outlook for 2021

The favorable weather development in 2020 led to a slowdown in the development ofbark beetles and the spread of infestation in the first half of the growing season, thanks towhich there was no further sharp increase in calamity in terms of the volume of infestedwood.

With the currently high logging levels, a significant part of the infested timber washarvested; for instance, state forests entered 2021 with a significantly lower recordedunprocessed balance than in previous years (only 34% of the state in 2019). Nevertheless,4.027 million m3 w.b. of bark beetle wood in the forests of the Czech Republic remainedunprocessed as of 31 December 2020. These statements are illustrated in Figures 3 and 4.

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Figure 3. Development of total felling. Source: [49].

Figure 4. Development of salvage felling. Source: [49].

Based on the current development of felling intensity in spruce stands or the stands with a predominance of coniferous trees and the current weather pattern, the total volume of incidental felling in connection with the processing of the bark beetle calamity in 2021 could be estimated within the range of 25–30 million m3.

3.4. Timber Flow Model for the Czech Republic (Data of the 2017 Base) Within the project entitled “Potential for structural changes in sustainable forestry

and wood processing” [51], a model of wood flow between individual branches of the forestry and timber complex (FTC) for the Czech Republic was created, which is shown in Figure 5.

For this model, input data were processed to create a cascade of wood flow based on verifiable factual information, which is generally available, namely the revenues of wood

Figure 3. Development of total felling. Source: [49].

Energies 2022, 14, x FOR PEER REVIEW 8 of 16

Figure 3. Development of total felling. Source: [49].

Figure 4. Development of salvage felling. Source: [49].

Based on the current development of felling intensity in spruce stands or the stands with a predominance of coniferous trees and the current weather pattern, the total volume of incidental felling in connection with the processing of the bark beetle calamity in 2021 could be estimated within the range of 25–30 million m3.

3.4. Timber Flow Model for the Czech Republic (Data of the 2017 Base) Within the project entitled “Potential for structural changes in sustainable forestry

and wood processing” [51], a model of wood flow between individual branches of the forestry and timber complex (FTC) for the Czech Republic was created, which is shown in Figure 5.

For this model, input data were processed to create a cascade of wood flow based on verifiable factual information, which is generally available, namely the revenues of wood

Figure 4. Development of salvage felling. Source: [49].

Based on the current development of felling intensity in spruce stands or the standswith a predominance of coniferous trees and the current weather pattern, the total volumeof incidental felling in connection with the processing of the bark beetle calamity in 2021could be estimated within the range of 25–30 million m3.

3.4. Timber Flow Model for the Czech Republic (Data of the 2017 Base)

Within the project entitled “Potential for structural changes in sustainable forestry andwood processing” [51], a model of wood flow between individual branches of the forestryand timber complex (FTC) for the Czech Republic was created, which is shown in Figure 5.

Energies 2022, 15, 47 9 of 16

*production of matches, special pencil cutters,

production of peeled and turned columns,

poles, palisades and rounded products

FOREST TIMBER HARVESTING

NON-FOREST TIMBER

HARVESTING

19.4 mil. m3

? mil. m3

IMPORT

OF TIMBER

1.6 mil. m3

EXPORT

OF TIMBER

5.7 mil. m3

FIBERWOOD

PULPWOOD

ROUNDWOOD

SAWMILL

PRODUCTION

TIMBER

OTHER

PRODUCTION*

BIOMASS

ENERGY

PRODUCTION

BOARDS

MATERIAL

PRODUCTION

INDUSTRIAL TIMBER FUELWOOD LOGGING

RESIDUES

PULP

PRODUCTION

3.34 mil. m3

SAWN

TIMBER

PRODUCTION

8.5 mil. m3

PLYWOOD

AND VENEER

PRODUCTION

0.215 mil. m3

PARTICLE

BOARD

PRODUCTION

1.7 mil. m3

ENERGY

PRODUCTION

>4.5 mil. m3

PELLET

PRODUCTION

CHIPS

SAWDUST

BARK

4.4 mil. m3

1.3 mil. m3 1.6 mil. m3

RECYCLATE FROM

CONSUMPTION INDUSTRIAL CONSUMPTION: 13.8 mil. m3

12.9 mil. m3 2.4 mil. m3 2.1 mil. m3

>1.3 mil. m3 1.2 mil. m3

up to 13 mil. m3

0.6 mil. m3

Figure 5. Timber flow model for the Czech Republic.

For this model, input data were processed to create a cascade of wood flow basedon verifiable factual information, which is generally available, namely the revenues ofwood processing companies published in the collection of deeds. Based on the retroactivecalculation of the produced volume of products and the application of material decaycoefficients, it is thus possible to create a framework for the flow of raw materials inprimary processing and, based on partial refinements implemented in the last stage of theproject, create a real wood flow model. Its correct evaluation required choosing adequateindicators expressing the efficiency of processing, both absolute and relative, related to acertain economic or physical value.

For the model of timber flow between individual FTC branches for the Czech Republicto show theoretical volumes of timber flows between individual segments derived fromthe 2017 base, it is necessary to correct the volumes of flows from forest logging by at least

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a 7% decrease in timber stock in forest stands between 2017–2019 and a 22% decrease intotal felling opportunities by 2027 or 2030.

3.5. Partial Conclusions of the Results

Based on the data presented in Sections 3.1–3.4, it can be concluded that in the years2017–2020, the total timber stock in economically usable forest stands in the Czech Republicdecreased due to an enormous increase in incidental logging, mainly processing sprucewood due to the bark beetle calamity, and including a decrease in the total current incrementof 20.79 million m3 of timber to the top of 7 cm o.b. (3.2% to the base of 2017). Whilerespecting the prediction of felling volume for 2021 and the outlook for bark beetle calamityprocessing until 2024, it can be estimated that the maximum total felling possibilities forthe decennium 2027–2036 will decrease by ≥7%, i.e., to an annual volume ≤ 13.73 millionm3 of timber to the top of 7 cm o.b.

Based on all data and partial conclusions from the previous chapters, it is possible todeduce and estimate the total annual available volume of dendromass, including forestbiomass, for energy production in the Czech Republic for the period extending up to 2036in the structure shown in Table 3.

Table 3. Estimation of the total annual available volume of dendromass for energy production in theCzech Republic for the period extending up to 2036.

Type of Forest Biomass

Fuelwood 8.165 mil. m3 up to 7 cm w.b.Forest residues 4.185 mil. m3

Pre-production 5.169 mil. m3

Non-industrial wood production 1.488 mil. m3

Non-industrial wood recyclate 0.558 mil. m3

Secondary production 2.200 mil. m3

Total 21.765 mil. m3/year(13.473 mil. t/year)

This derived and estimated value must currently be considered as the maximum andlimit for the following reasons:

• An absolute decline in logging opportunities in Czech Republic forests.• An absolute increase in the processing capacity for saw logs of the forestry and timber

complex sawmill segment of approx. 0.89 million m3 in 2021 and 1.00 million m3 in2022, thanks to commissioning the LABE WOOD plant in Štetí and increasing thecompetitive environment in the sawmill industry segment, which will translate intoincreasing wood prices after the bark beetle calamity has subsided.

• Interest in the maximum utilization of the production capacity of MONDI Štetí, a.s., i.e., an escalation of the competitive and pricing environment in the segment ofpulpwood and white (paper) chips.

• Increasing social pressure on increased retention of logging residues and timber fordecay in forest stands intending to improve the retention capacity of forest soils(postponed effectiveness of Section 33 (3) of Act No. 289/2015 Coll., On Forests andon Amendments to Certain Acts [47]).

• Increasing social pressure on the production of wood-based products as renewablewood raw material, with a long period of carbon sequestration to achieve carbonneutrality by 2050 (see [3]).

A significant problem for meeting European commitments in the area of carbonneutrality and the share of RES in the Czech conditions is not only the total volume ofavailable raw materials but also the share of wood chips in the total annual production,upon which mainly small and medium heating plants are primarily dependent. As woodchips are a commodity with a limited shelf life due to their relatively short life cycle,

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their annual volume is an essential parameter for assessing the possibilities of increasingthe energy potential of the Czech Republic, especially if the estimates do not account forregrouping resources from other sectors and segments within the timber processing cascade(Figure 5).

Data on the volume of wood chips at the national and international statistics levelwere used to define the actual potential for meeting the Czech Republic’s objectives inincreasing the share of RES (significant differences were identified in the interpretation ofdata from FAO and MoA reports). Based on the available statistics, we can speak of anavailable annual volume of wood chip resources at a level of 2 million. m3 (2016) to approx.2.75 million. m3 (qualified estimate for 2020) from data of the Ministry of Agriculture,and 1.395 million. m3 (2016) to 1.676 million. m3 (2020) from FAO data, which representsa relatively large statistical variance. The information provided can be substantiated byTable 4. At the same time, the above statistics point to a relatively low percentage of woodchips related to total felling over the last five years, despite a significant increase in fellingvolume.

Table 4. Annual available volume of wood chips in 2016–2020 related to total felling.

Year 2016 2017 2018 2019 2020

Felling volume (in mil. m3) 17.610 19.390 25.690 32.590 35.760Wood chips, particles and residues (in mil. m3) 1 2.0 2.1 2.2 2.5 2.75

% share in total felling (in %) 11.36 10.83 8.56 7.67 7.69Wood chips, particles and residues (in mil. m3) 2 1.395 1.412 1.547 1.676 1.676

% share in total felling (in %) 7.92 7.28 6.02 5.14 4.691 Zpráva o stavu lesa 2017–2019 (Report on Forest Conditions [2017–2019]), Source [49]. 2 FAO-Forestry Productionand Trade, Source [55].

Data from the NAZV project were used to refine the estimate of the potential volumeof wood chip production in the wood processing cascade in the Czech Republic. In thecase of the data from the NAZV project, the calculation includes the volume producedwithin the primary wood processing, i.e., during the industrial production of productsfrom sources for industrial use in the processing cascade. These statistics do not includethe volume of wood chips, bark, and sawdust delivered to the market from other sourcesand imports.

From the above data from Table 5, we can talk about the current volume of woodchips produced in the Czech Republic at a level of 2.9–3.5 million tons in 2016–2020. Theselected period is associated with the historically highest logging volume in the CzechRepublic. In connection with the limitation of the maximum felling possibilities for thedecennium 2027–2036 to approximately 13.7 million m3 and the forecast, which foreseesthe total volume of primary dendromass for energy purposes of 7.645 million tons peryear, the setting of the Czech Republic’s goals regarding the shares of RES in gross finalconsumption seems overly optimistic.

Table 5. Annual volume of forest chips produced in the Czech Republic in 2016–2020.

Year 2016 2017 2018 2019 2020

Wood chips, sawdust, bark (in mil. m3) 3.955 4.267 4.403 4.820 5.108Calculation per prm (in mil. of prm) 1 9.611 10.370 10.700 11.713 12.414Calculation per tons (in mil. of tons) 2 3.495 2.986 3.081 3.373 3.575

1 TZB: Výhrevnosti a merné jednotky palivového dreva [Calorific values and specific units of firewood], Source[56]. 2 LCR-Drevní hmota: Obnovitelný zdroj energie [LCR—Wood Substance: A Renewable Energy Source],Source [57].

4. Discussion

Renewable energy is one of the basic pillars of the European Union’s energy andclimate protection strategy extending to 2030 and beyond. From 2009 to 2020, the European

Energies 2022, 15, 47 12 of 16

Union’s energy policy had three main objectives: security of supply, development of acompetitive energy sector, and environmental sustainability [45]. In 2010, the Europe 2020Strategy set a target for RES to increase their share in the gross final energy consumption to20% by 2020 [46]. EU countries subsequently issued so-called national renewable energyaction plans to increase renewable energy production [21,42]. EU countries have thus settheir targets for 2020. The Czech Republic set this target at 13% by 2020. Data for 2019 [5]are currently available, showing the progress in developing the use of RES and the stateof meeting the targets for individual EU countries. For the EU, meeting the 2019 targetwas almost within reach. Until about five years ago, however, the goals in the field of RESseemed too ambitious [58,59]. In 2019, the share of RES was 18.88% for the EU-28, but ifthe United Kingdom is left out, then this share is 19.73%; hence, the target for 2020 waslikely met. The Czech Republic had already met its target in 2013 when the share of RESwas 13.93% [5].

For the next period, i.e., until 2030, the target is 32% for the EU and 22% for the CzechRepublic. Dendromass plays an important role in achieving the EU’s goals [58], as otheroptions are not very realistic due to weather, economic, political, and other obstacles. AClean Planet for All [10] states that sustainable biomass will play an essential role in aneconomy with zero net greenhouse gas emissions. Wood-based bioenergy is currentlythe main source of renewable energy, accounting for 60% of the EU’s renewable energysupply [44]. The importance of biomass and its share in RES is therefore undeniable.

As stated in [58], for example, the targets appear realistic if conditions such as reducingenergy consumption, mobilizing dendromass from the available potential, or increasingdendromass imports are met. In other words, those conditions leading to climate neutralityset out in point d of the Climate Act [1]. In the case of the countries that have set increasingthe share of biomass in RES from their resources as one of their goals, such as the CzechRepublic, it is necessary to meet another condition, namely ensuring the secure supply ofthis energy source. The same concerns about the potential, quantity, and supply of biomasshave been addressed in various studies [21–24]. The authors agreed that in the case ofbiomass from forests, trunks, and forest residues, it is not possible to expect a sharp increasein supply by 2030. However, the publications do not account for the possible occurrenceof biotic or abiotic harmful forest factors causing calamities, as is the case in the CzechRepublic.

The IPCC recognizes that biomass from trees affected by natural disturbances cancontribute to the overall technical potential of forest biomass [35]. On the contrary, stud-ies [40,41] assume that in Central Europe, the supply of forest biomass for energy purposeswill be endangered due to the bark beetle calamity and the consequent large-scale defor-estation. The presented research substantiates this statement.

Experience from Canada [60] shows that low-quality trees in forests can be an im-portant source of raw material for the bioenergy industry, provided that the long-termproduction capacity of the forest is maintained. In the Czech Republic, the supply of woodin forests decreased, and with it the overall potential of dendromass for energy purposes.Even strategic documents such as The National Energy and Climate Plan of the CzechRepublic [6] do not envisage an increase in the use of forest biomass for energy purposesby 2030, and even state that in areas with a high intensity of incidental logging, biomassshortages and rising prices for bioenergy can be expected.

Based on data and calculations, the total available volume of dendromass for energyproduction in the Czech Republic for the period up to 2036 was estimated at 7.645 milliontons per year from primary production and 13.473 million tons from the total production. Atpresent, therefore, it is clear that the Czech Republic will probably not be able to achieve thenew goal in the field of energy production from forest biomass to which it has committed.

Due to their inconsistency, the analytical data available at the national (Ministry ofAgriculture) and international (FAO) levels represent a problematic level for making a pre-dictive estimate of the development of possibilities of increasing the volume of dendromassfor energy purposes, as well as the actual decision-making concerning increasing energy

Energies 2022, 15, 47 13 of 16

capacity. Other major shortcomings are the norms, standards, methodologies, and conver-sion tables for determining the weight and volume coefficients for the conversion of massto m3, prm, and tons, which differ for the areas of transport, processing, and consumptionwithin individual sectors. Based on aggregate statistics of the total available volume ofwood chips without lower decay granularity within the wood flow, it is impossible todefine the energy sectors’ actual consumption. The elimination of shortcomings leading tomore accurate statistical reporting on available capacities of wood chips and other inputsources for energy use could realize the possibilities, perspectives, and ambitions of theCzech Republic in setting and achieving the EU’s RES targets and the potential to increaseenergy inputs so as not to affect the carbon neutrality objectives.

On 14 July 2021, the European Commission published a new climate and energylegislative package called the “Fit for 55 Package” [43], containing 13 legislative proposalsto enable meeting the set 2030 emission target. The proposals also include amendmentsto the RED II [4], such as increasing the share of renewables in the energy mix from 32%to 40%. Another novelty, for example, is the introduction of a ban on state support forelectricity production from forest biomass, starting in 2026, sustainability criteria that mustalso be applied to biomass, and the production size limits that must monitor compliancewith sustainability criteria in order to receive state aid have decreased from 20 to 5 MW (forplants using solid biomass). One of the proposals also confirms the principle of cascadingresource use, in which the use of wood with the highest added value is given priority [61].A new EU Forestry Strategy was presented together with the Fit for 55 package [43]. Thestrategy states, inter alia, that wood-based bioenergy in the EU is predominantly (49%)based on residues and waste from logging and wood processing (e.g., branches and crowns,sawdust, wood waste). Another 37% comes from so-called “primary biomass sources”,including low-quality logs and pellets (20%), half of which are logs (10%) from woodyplants grown in coppice plantations, while 4% come from industrial-quality logs. Theremaining 14% is not listed in any category in the reported statistics, which means it isnot classified as a primary or secondary source; however, in light of wood biomass flowanalyses, the source is more likely to be primary wood. In the context of the above, the twoEuropean Strategy documents [62] thus contradict each other significantly.

5. Conclusions

In 2013, the share of renewable energy sources in the total gross final energy consump-tion in the Czech Republic was 13.93%. In 2019, the share amounted to 16.24%, representinga total increase of 2.31 percentage points over six years (0.385 percentage points annually),with a relatively stable share of forest biomass in the fuel mix and the total energy mixbetween 2014 and 2017. A more significant increase in the share of forest biomass in thefuel mix has only been occurring since 2018 due to a surplus of firewood and loggingwaste from primary production due to the culmination of bark beetle calamity felling.This increase must be marked as temporary, considering the current development in theintensity of felling spruce stands or stands with a predominance of coniferous trees. Adecline in the intensity of harvesting in forest stands is expected to possibly occur in 2022,with a positive watershed in the development of the bark beetle calamity and a temporaryreduction in standing volume, including a decrease in total current increment. However,the temporary nature of the decline in logging opportunities and the reduction of the rawmaterial base compared to the current level represents a period of at least 30 years.

The results of this study show that the total annual available volume of dendromassfor energy purposes in the Czech Republic extending until 2036 amounts to 13.473 milliontons, with an annual share of forest biomass from primary production of 7.645 milliontons (56.7%). Until 2018, the annual volume averaged 13.880 million tons. Supposing theobjective share of renewable energy sources in the total gross final energy consumption isset at 22% by 2030 (an overall increase of 5.76 percentage points/0.523 percentage pointsannually), it should be stressed that the share of forest biomass from primary productionin the fuel mix is currently at its maximum available limit. Further increasing the share

Energies 2022, 15, 47 14 of 16

through 2030 while maintaining sustainable forest management principles is no longerpossible. Further increase could jeopardize the security of supplies in the long-term view (by2050), including the risk of deformations of timber raw material markets in the assortmentsof technological processing, logs and timber for the pulp and paper industry, and theproduction of timber-based agglomerated materials.

Author Contributions: Conceptualization, J.M. and P.H.; methodology, D.Š.; validation, P.H. and J.M.;investigation, D.Š.; resources, D.Š.; data curation, P.H and J.M.; writing—original draft preparation,P.H.; writing—review and editing, P.H.; supervision, P.H and D.Š.; project administration, J.M.;funding acquisition, D.Š. All authors have read and agreed to the published version of the manuscript.

Funding: This research was funded with support from the Ministry of Agriculture, project numberOK1820358.

Institutional Review Board Statement: Not applicable.

Informed Consent Statement: Not applicable.

Data Availability Statement: The data presented in this study are available on request from thecorresponding author.

Conflicts of Interest: The authors declare no conflict of interest.

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