Green Partnerships – WP3 Joint approach for more efficient
implementation of local energy strategies
Expert Working Groups
Biomass
CONTENTS
1.
Introduction .......................................................................................................................... 3
2.
Strategic and economic prospects ........................................................................................ 3
3.
Biomass Availability ............................................................................................................... 4
4.
5.
3.1.
Data Sources.................................................................................................................. 4
3.2.
Selection of forest and agricultural areas ..................................................................... 5
3.3.
Biomass Availability ....................................................................................................... 6
3.4.
Available Energetic Potential ........................................................................................ 6
3.5.
SIG Implementation ...................................................................................................... 6
3.6.
Fieldwork ....................................................................................................................... 7
3.7.
Results ........................................................................................................................... 9
Use of biomass for thermal purposes in public buildings ................................................... 11
4.1.
Biomass systems ......................................................................................................... 11
4.2.
Applications ................................................................................................................. 12
4.3.
Decision Steps to Biomass Heating ............................................................................. 13
4.4.
Example ....................................................................................................................... 14
Case Study ........................................................................................................................... 16
1. Introduction
Sustainable development has increasingly become a priority in many communities and one of
its main elements is related to the production of energy from environmentally adequate
sources. In this sense, bioenergy, as energy obtained from biomass, presents itself as one of the
most popular alternatives to fossil fuels, with conditions to be an effective solution to the
current environmental and energetic issues. In fact, biomass is the only renewable energy
source (if used sustainably) that can be converted into gaseous, liquid or solid fuel by means of
known technologies for conversion.
Currently, we can use energy produced from biomass in several applications, ranging from
heating and electricity production to fuel supply for transport sector. Thus, bioenergy has
potentially the ability to offer support sustainable structural development in rural areas.
Biomass is a term used to describe all the (non-fossil) contemporary organic materials that arise
from the conversion of sunlight through photosynthesis, including agricultural and forest waste,
energy crops and organic waste from industrial and domestic activities.
2. Strategic and economic prospects
The option of promoting and increasing the use of renewable energy drags benefits not only in
terms of prevention of fossil resources’ decrease, but also the level of autonomy and reduction
of energy dependence on external sources that, due to the current and constant political and
social instability in some countries, are not always guaranteed.
The energetic valuation of organic waste associated with biomass has also a number of
externalities arising from the implementation of management and exploitation operations.
These influences can be environmental or non-environmental and include:

Reduction of CO2 emissions and other greenhouse gases into the atmosphere if the
resource is sustainably used; the reduction of problems associated with erosion and
desertification; the contribution to the cleaning of forests and the forest regeneration;
reducing the risk of fires and easiness in their extinction;

The diversification of energy sources; increased certainty regarding the cost of energy;
the lowest susceptibility to political and social instability in the exporting countries; the
decrease in transportation costs of electricity due to the decentralized location of
production; more jobs due to market growth associated with bioenergy; promoting
sustainable development translated into a decrease in the use of fossil energy; greater
rural development and improving equity between regions; positive impact on the
industrial sector, employment opportunities and settlement of populations in rural
communities.
3. Biomass Availability
The assessment of the potential biomass in a given region can be developed using a Geographic
Information System (GIS), which integrates different kinds of spatial and geographic information
in its own database. The use of this type of tool will allow, firstly, the storage and compilation of
information efficiently, and have greater ability to model and analyse a range of relevant factors
when the theme is bioenergy. Specifically, GIS tools can be used as dynamic environments in the
analysis of the geographical distribution of the residual biomass from forest and livestock, thus
allowing the identification and integration of various parameters that affect the potential
biomass available.
The benefits in using this tool are those linked to geographical and graphical visualization, since
the presentation of summary statistics and simple sets of data in map format with site
information, is considered as more pleasant when compared to a more traditional presentation
(paper maps).
3.1.
Data Sources
The data sources to be used for the development of the biomass potential survey in a region
must contain the following elements:

Administrative Charts;

Charts of Soil Occupancy;

Digital Terrain Models;

Cartography (various scales);

Production Factors (per crop);

Calorific value (per crop).
3.2.
Selection of forest and agricultural areas
Taking as an example the methodology for biomass mapping in North Alentejo region (Portugal),
developed in 2011, and considering an evaluation focused on the resource (bottom-up
methodology), with estimation of the physical potential of biomass at regional level and adding
a number of technical constraints on its use, taking into account the data sources abovementioned.
This first evaluation after the crossing with statistical information on the production of biomass
and information on the calorific value of each vegetation capable of estimating the amount of
biomass and the amount of which can be truly exploited and turned into energy.
Note that the evaluation of biomass potential took into account only the main species. A
graphical representation of agricultural crops and forest species in North Alentejo can be found
in Figure 1.
Figure 1 – Graphical representation of agricultural crops and forest species in North Alentejo
3.3.
Biomass Availability
After the general quantification of existing forest and agricultural areas through a geographical
analysis of administrative boundaries and land use of the total study area, proceeded to the
classification of these areas according to the road network and altimetry, considering that
collection of residual biomass would be subject to some technical restrictions, having excluded
from areas with slope greater than 20% or located more than 3 km of a road or passable path.
3.4.
Available Energetic Potential
The energetic potential was defined as a quantification of the energy from waste biomass found
within the administrative boundaries of the total study area. The expression used for the
estimation was as the following one:
𝐸𝑑 = 𝐵𝑑 ∗ 𝑄 ∗ 𝜂 𝑇
Where:

𝑄 represents the lower calorific value of each type of biomass waste (GJ/ton);

𝜂𝑇 the efficiency of transformation of the resource into energy;

𝐸𝑑 available potential energy (GJ / year).
3.5.
SIG Implementation
The tools provided by several existing GIS software in the market allow the combined use of
different data sources needed to quantify the potential associated with biomass as reliably and
analysis, editing and integrated visualization.
In the case of North Alentejo region, the final estimation of the availability of biomass made up
as follows:
1. Import of data on usable areas (reclassified taking into account only the main species)
for a table of attributes with content relating to production factors and calorific values
of each species;
2. Calculation of availability of biomass in tons/year;
3. Graphical representation of data in a GIS format.
The development of the layer corresponding to the area capable of producing agro-forestry
biomass can be obtained from the intersection with the layers corresponding to the areas
effectively usable according to the criteria classification considered (route distances and slopes
less than 20% and 3 km, respectively).
Figure 2 – Integrated classification according to criteria presented. Four categories represent possible combinations
between the distance classes and slope classes. This information allows predict the type of collection (manual or
mechanized collection) as well as the ease / difficulty of access biomass.
3.6.
Fieldwork
The diversity of sources than can be classified as biomass as well as the lack of ground data with
detailed information on each culture may lead to the necessity to move to a more detailed
characterization of the region to be analysed, in the form of a fieldwork.
Effectively, as the main objective of the study is to define the territorial capacity of the region
regarding the implementation of bioenergy projects, it is quite interesting to use the
methodology previously identified to make a first qualitative analysis (although necessarily brief)
of some characteristics of different types of biomass available in the region.
The background methodology used to define the places of Alto Alentejo region visited during
the fieldwork was similar to the one used in mapping the biomass potential. Basically, the initial
procedure corresponded to a general quantification of forest and agricultural existing areas
through the integrated analysis of administrative boundaries and land use of the entire region,
also applying a set of representative technical restrictions of the difficulty in accessing the
resource.
In Figure 3 are represented, respectively, the model structure of the methodology used in the
identification of the places subjected to fieldwork and the selected cells for their realization.
Figure 3 – Cells selected for conducting the fieldwork
Once identified the places, we must prepare the interventions in the field throughout the
identification of the centroid coordinates of the selected cells to a GPS device in order to
facilitate the identification in the field. The preparation of data sheets for field data recording
can be an asset for a more detailed and comprehensive characterization.
3.7.
Results
The fieldwork took place in 9 Municipalities belonging to Alto Alentejo region and was
distributed by 97 cells of approximately 197 ha. In Table 4 we can find a summary of the number
of cells visited in each county and the corresponding percentage of effective area of vegetation.
The surrounding was visually characterized as close to the centre of each cell and was mainly
characterized by the existence of pastures, forest plantations of holm oak (Quercus rotundifolia),
cork oak (Quercus suber) and eucalyptus (Eucalyptus globulus) and, on a smaller scale, rainfed
crops and olive groves, among other types. We can find the detailed list of data collected during
the execution of the work in ALTERCEXA Platform (http://altercexa.irradiare.com).
This biomass mapping developed under ALTERCEXA Project was at the origin of BIOATLAS
Project (www.bioatlas.pt), which aims the development of a national biomass mapping
(Portugal) during the period 2014-2015. This Project aims to provide the biomass sector for
energy purposes of an instrument of geographical information which may aggregate a set of
data, methodologies and scientific knowledge in an integrated way or a “user-friendly”
interface.
4.7.1.
Availability of Biomass
The availability of biomass was obtained by the disaggregation of the amount of waste in
different classes within the GIS database. For instance, the graphical representation and the
geographical distribution of biomass availability was performed using ten classes of colour, as
illustrated in Figure 4.
Figure 4 – Geographical distribution of biomass availability (tons/year)
4.7.2.
Available Energy Potential
The energy potential was calculated based on the total waste of the area and the calorific value
of each type of biomass waste. We considered as well a conversion efficiency of 25% in energy
(electricity).
They were created as well ten classes of colour used to graphically represent energy potential
associated with the resource and its geographical distribution in the study area. The results are
shown in Figure 5.
Figure 5 – Geographic distribution of energy potential (GWh / year)
4. Use of biomass for thermal purposes in public buildings
Biomass is used for facilities’ heating and, to a less extent, for electric power generation and
combined heat and power. The term biomass encompasses a large variety of materials, including
wood from various sources, agricultural wastes, and animal and human waste. The focus of this
section is limited to woody biomass for heat only.
4.1.
Biomass systems1
Woody biomass systems commonly use wood biomass for facility heating in three forms:

whole logs or firewood

wood chips

wood pellets
Biomass systems require more operator interaction than other renewable energy systems such
as solar and wind. This includes ordering and delivering fuel, removing ash, and maintaining
moving parts. Generally, however, biomass heating systems typically require only a few minutes
of attention each day, plus a few hours per year for annual maintenance.
A biomass heating system is made up of several key components, which include some
combination of the following items:
1

Fuel storage and handling/conveying

Combustor

Boiler

Fire suppression systems

Pumps

Fans

Exhaust / emissions controls

System controls

Automatic ash handling (optional)

Backup boiler

The building facility's heat distribution system.
http://www.wbdg.org/resources/biomassheat.php
Biomass heating systems often include a secondary fossil fuel-fired heating unit. This offers
several advantages, including:

Reduced capital costs and increased operating efficiency by under-sizing the biomass
system;

Reduced uncertainty, as the buildings will still have a heat source even if the biomass
system is down for any reason;

Increased operational flexibility;

Increased fuel options.
Direct combustion is the most common method of producing heat from biomass. In a direct
combustion system, the biomass is burned to generate hot gas, which is either used directly to
provide heat or fed into a boiler to generate hot water or steam. In a boiler system, the steam
can be used to provide heat for process or space heating. The hot water or steam from the boiler
can be used to transfer heat to a facility through typical space heating methods.
4.2.
Applications
The type of system best suited to a particular application depends on many factors, including:

Availability and cost of each type of biomass (e.g. chip, pellet);

Competing fuel cost (e.g. fuel oil and natural gas);

Thermal peak and annual load;

Building size and type;

Space availability;

Operation and maintenance (O&M) staff availability;

Local emissions regulations.
The following recommendations are critical to the success of any biomass energy project.

Work closely with a biomass equipment manufacturer or seller to coordinate on building
design and equipment requirements;

Coordinate building scheduling with the equipment delivery. For example, it is easier to
deliver and install the equipment if a crane can access the installation site;

Identify a fuel delivery route, to ensure that trucks can reach the storage area easily and
turn around, if necessary.
4.3.
Decision Steps to Biomass Heating
4.3.1.
Screening
The purpose of the screening step is to see if a wood-fired heating system makes sense for a
particular facility. A quick economic analysis should be performed to estimate capital costs
relative to potential annual savings. A discussion should be held with O&M staff, management,
and other affected parties to determine the building characteristics to support biomass heating.
4.3.2.
Conduct Research
If the concept of biomass heating passes the initial quick filter, it is time to learn more about
biomass heating systems. Review manufacturers' websites and literature, talk to others with
knowledge of biomass heating, and consider scheduling an appointment to visit similar regional
installations.
4.3.3.
Assess the Local Biomass Resource
Research the cost and availability of biomass fuel in the area and keep in mind that long haul
distances increase chip cost. Search for potential suppliers that are able to deliver wood chips
to the designated facility. Eventually there will be a need to select one or more suppliers whose
delivery vehicles are compatible with the chosen system.
4.3.4.
Conduct a Feasibility Study
At this stage, it would be profitable to have a feasibility study performed by a company with
experience in biomass heating systems. The study will cover most of the topics in this document
and will provide a detailed economic analysis of heating and comparison of wood versus
conventional fuel. The feasibility study can also determine how well a biomass heating system
will help meet the facility's energy requirements and goals.
4.3.5.
Determine Suitable System Size
The size of the wood-fired system should be based on the peak load. Compared to an undersized
system, an oversized system will not perform as well, will be inefficient, and will have higher
emissions. An additional boiler, using a conventional fuel, will almost always be needed and will
be sized to meet the peak load. The wood-fired boiler can be sized at 50% to 80% of the peak
load, and still meet 90% to 95% of the annual load. The smaller system will have lower capital
costs and will operate more efficiently than a large system. An economic analysis can be used to
determine the optimal size of the wood-fired system.
4.3.6.
Estimate Heating Energy Use
Estimate heating energy use and expenses for a wood-fired system and for a system using
alternate fuel such as natural gas, propane, and heating oil. The annual cost of wood versus
alternate fuel will be a factor in the economic analysis, and will also be used to estimate CO2
emissions, ash production, fuel storage requirements, and wood delivery schedules.
4.3.7.
Make the Decision
After the gathering of enough information, it is time to decide if proceeding with a biomass
heating system fulfils the facility's specific needs, goals, and economic requirements.
4.4.
Example
Dimensioning of a biomass system to an existing municipal pool in Alto Alentejo region
1. Characterization of the building:
In order to meet the energy needs of the Sports Complex for water and environment heating,
the facility consumed an average of 31.674 kg of propane gas, equivalent to an annual cost of
about 28.570 Euros.
The usage of the Sports Complex is around 66 users per day, which corresponds to an annual
thermal load of 305.737 kWh.
According to the Sports Complex’ needs, as well as the current conventional system used, we
considered the acquisition of a pellet boiler system with a power of 430 kW. These needs
correspond to an average investment of 87.650 Euros.
2. Initial Consumption Values:
Facility
Number of
users
(annual)
Energy
consumption
(kWh)
Energy costs
(€)
CO2
Emissions
(t)
Swimming Pool
1.980
306.000
28.500,00 €
89,40
3. Description of the system and technology installed
1 (one) biomass boiler (pellets and/or chips) for hot water and heating of the swimming pool’s
tank. It included one storage system of pellets/chips and a feeding system of the boiler, with the
aim of replacing the existing propane boilers (propane boilers equipped with burners of 440
kW).
The biomass storage system (pellets/chips) consists of an iron silo with proper capacity and
which allows an autonomy of at least 2 weeks between higher thermal requirements.
4. Annual results to be obtained
In terms of contribution of renewable energy sources and reduction of energy costs and CO2
emissions, we can point out the following annual results:
Facilities
RES contribution
(kWh)
RES contribution (%)
Reduction of CO2
Emissions (t)
Swimming Pool
306.000
100%
89,40
5. Case Study
Country
Portugal
Entity
CIMAA – Intermunicipal Community of Alto Alentejo
AREANATejo – Regional Energy and Environment Agency from North Alentejo
Municipality of Sousel
Portugal
Location
Sousel, North Alentejo, Portugal (38.955501, -7.670803)
Identification of the
Best Practice
Installation of a biomass system in the Sports Complex of Sousel
Main area
Biomass
Summary
In order to meet the energy needs of the Sports Complex for water and environment heating,
the facility consumed yearly an average of 31.674 kg of propane gas, representing an annual
cost of about 28.570 Euros. The usage of the Sports Complex is around 66 users per day, which
corresponds to an annual thermal load of 305.737 kWh. Taking into account the Sports
Complex’ needs, as well as the current conditions (namely the installation of a thermal solar
system in 2011), a biomass pellet boiler system with a power of 430 kW was installed in 2013
involving an investment of 87.650 Euros.
Target Group
Municipal technicians; Facility users
The use of biomass constitutes a clear opportunity to create conditions for the growth of a
low carbon economy , thus encouraging innovation and development of new cleaner
technologies by strengthening and diversifying the energy use of various forms of biomass ,
especially residual forest biomass:
Description






Electricity production from dedicated plants;
Joint production of thermal and electric energy - cogeneration and trigeneration;
Production of thermal energy - heat/air cooling/hot water;
Production of energy in industrial processes;
Production of biofuels;
Heating of public and multifamily buildings.
Replacing conventional boiler systems that rely on fossil fuels for boilers systems using
biomass pellets constitutes a viable solution and presents very favourable long-term
environmental and economic results despite the initial investment.
Date
Starting date (operation): December 2013
Technical Aspects
1 (one) biomass boiler (pellets and/or chips) for hot water and heating of the swimming
pool’s tank. It included one storage system of pellets/chips and a feeding system of the
boiler, with the aim of replacing the existing propane boilers (propane boilers equipped with
burners of 440 kW).
The biomass storage system (pellets/chips) consists of an iron silo with proper capacity and
which allows an autonomy of at least 2 weeks between higher thermal requirements.
Implementation
approach followed
a) Implementation steps that were necessary for the provision of the concept
The project was developed according to the following items:
i.
ii.
iii.
iv.
v.
vi.
Identification of the thermal needs of the facility (306.000 kWh/year);
Sizing of biomass equipments considering the use/occupation of the facility (see
technical aspects);
Drafting of technical study of economic viability (see Economic Aspects);
Data presentation to local decision makers;
Drawing up procedures for the acquisition of equipments;
Installation and entry into force.
b) Stakeholders involved to the development
i.
Decision makers
ii.
Technicians
iii.
Designers
iv.
Building users
(1.500 characters including spaces)
Economic aspects
The installation of biomass systems in the Sports Complex of Sousel had a total investment
of approximately 88,000 euros, 75% co-financed by MED Programme, allowing a return of
investment in less than 2 years.
Using the feasibility study mentioned above, we can conclude that the implemented system
enables the following annual results:
i.
Full Replacement of propane gas (fossil fuel) consumption;
ii.
Reduce annual energy costs by approximately 12,500 euros, filling over 43.5%
of current expenses;
iii.
Neutral CO2 emissions.
100%
90%
80%
Results
70%
60%
50%
40%
30%
20%
10%
0%
Propane
Risks/Difficulties
Solar
Biomass
Currently the greatest existing difficulty in operating the biomass system installed on the
Sports Complex of Sousel is related to the acquisition of the primary fuel: biomass pellets.
Nowadays the national market is in very competitive situation and there is a lack of
availability of biomass pellets. Thus, and taking into account the thermal requirements, and
consequently the required amount of pellets (high), there are also some difficulties in
storage and transport of pellets to feed the boiler.
Photos
Additional
Documents
Links
Contact Person
Word, PDF, PPT…
www.medzeroco2.eu/
www.areanatejo.pt
Mr. Carlos Nogueiro – carlos.nogueiro@cimaa.pt
00351 245 301 440
Mr. Tiago Gaio – tiago.gaio@areanatejo.pt
Mr. Diamantino Conceição – diamantino.conceicao@areanatejo.pt
00351 245 309 084