Project “GREEN BARBADOS”
Electricity from Biomass –
A competitive alternative for base load
electricity production in large-scale applications
and an interesting opportunity for small-scale
CHP systems
Ingwald Obernberger
Peter Thonhofer
BIOS BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz, Austria
TEL.: +43 (316) 481300
FAX: +43 (316) 4813004
E-MAIL: office@bios-bioenergy.at
HOMEPAGE: http://www.bios-bioenergy.at
BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
Overview
 BIOS – a short introduction
 Biomass – a renewable energy source
 Biomass to power – large-scale applications
 Examples of large-scale power plants
 Biomass combined heat and power – small-scale applications
 Example for a small-scale CHP plant
 The role of biomass to power within the
“GREEN BARBADOS” project
 Summary and conclusions
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
BIOS – a short introduction
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
BIOS - Company information
 BIOS BIOENERGIESYSTEME GmbH, founded in 1995,
is an internationally active R&D and engineering company with
the main focus on bioenergy applications such as


District heating

CHP (combined heat and
power) applications

CHCP (combined heat,
cooling and power)
applications


Pelletizing plants
Process heating and
cooling
Hybrid (biomass/solar) plants
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz

BIOS – selected references
40 biomass CHP and CHCP plants –
based on ORC, steam turbine, screwtype engine, Stirling engine, vegetable
oil and biogas including hybrid plants

9 plants for waste heat utilisation

13 biomass district heating plants

3 pellet production plants

3 cooling plants (absorption chillers
and heat pumps)

more than 25 CFD simulation projects
(development, design & optimisation
of biomass combustion and
gasification systems)
Lienz / A – CHP plant & district heating
Marstal / DK – CHP plant & solar heating
Fussach / A – CHCP plant
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
Biomass – a renewable energy source
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
Biomass – a renewable energy source
 Biomass is a renewable energy source as long as it is used
sustainably (the harvested amount must not exceed the
growth)
 Advantages of using biomass:
 Biomass is chemically stored solar energy  thus, in
contrast to wind or solar power it can be used on demand
 Biomass is the renewable energy source with the highest
short- and medium-term application potential
 Prices of biomass are considerably more stable and lower
than of fossil fuels
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Energetic biomass utilization carbon and mineral cycle
BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
CO2 uptake via
photosynthesis
CO2 emissions
Biomass for
energy generation
(bound CO2 and minerals)
Recycling of ash back to
forest or short rotation coppice
plantations
Combustion residue
biomass ash
Uptake of nutrients
contained in the ash
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Biomass utilization –
example Austria
BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
100%
90%
80%
14.4
20.4
19.5
18.9
70%
60%
16.8
50%
0.1
0.8
22.4
21.5
11.7
11.9
1.7
2.5
2.1
25.3
11.4
26.1
10.2
18.5
22.6
42.3
43.2
42.7
40.9
36.2
1984
1994
2004
2007
2011
23.1
20.8
23
40%
30%
20%
49.4
not renewable waste
electricity
renewables
coal
natural gas
oil
10%
0%
1974
Total in 2011: 1,427 PJ; share of renewables: 28.2%
Target for 2020: 34% of renewables
Source: Austrian Biomass Association, 2013: Basic data Bioenergy Austria
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
Renewable energies and bioenergy
in Austria
Contribution of renewable energy
sources to the gross energy
consumption in 2011 [PJ]
Contribution of different sections on
the total bioenergy utilisation
in 2011 [PJ]
combustible
waste, 5.7
log wood,
60.6
hydro, 123.0
PV, 0.7
wind, 7.1
solar thermie,
7.1
Bioenergy,
228.8
waste liquor,
28.1
gaseous
biomass, 6.6
biofuels, 21.9
wood pellets,
12.1
heat pumps,
geothermal,
6.3
forest wood
chips, bark,
sawmill
residues,
80.2
Source: Austrian Biomass Association, 2013: Basic data Bioenergy Austria
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Percentage of the primary EU27
energy consumption covered by
renewable energy sources
BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
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Solar
Wind
Geothermal
Hydro
Biomass and waste
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8
7
6
EU27 – 2020 targets:
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 20% renewable energy in gross final energy
consumption
 cutting greenhouse gases by 20%
 reducing energy consumption by 20% through increased
energy efficiency
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3
2
1
2010
2009
2008
2007
2006
2005
2004
2003
2002
2001
2000
1999
1998
1997
1996
1995
1994
1993
1992
1991
1990
0
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
Worldwide energy consumption
Overall (2011)
Source: World Biomass Association
Electricity
production
(2013)
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
Fuels used in
biomass combustion plants
 Woody biomass fuels







Bark
Industrial wood chips
Sawdust
Forest wood chips
Short rotation coppice
Waste wood
Pellets, briquettes
 Herbaceous biomass fuels
 Straw, cereals
 Grasses (miscanthus, giant reed)
 Alternative biomass fuels
 Kernels, shells, rice husks etc.
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Fuel selection and appropriate
conversion technology
BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
 The selection of biomass fuel sources is important since
the fuel quality differs from species to species
 As a consequence, the biomass conversion technology
needs to be adapted to the fuels available
ash content wt% (dry basis)
moisture content wt% (wet basis)
8,0
7,0
6,0
5,0
4,0
3,0
2,0
1,0
0,0
70,0
60,0
50,0
40,0
30,0
20,0
10,0
0,0
Wood chips
Bark
Straw
Waste wood
Poplar (SRC)
Pellets
Wood chips
Bark
Straw
Waste wood
Poplar (SRC)
Pellets
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
Biomass to power – large-scale
applications
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Technologies for
industrial biomass combustion
BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
fuel
bed material
freeboard
secondary
air
secondary
air
secondary
air
bed
material
bed
material
fuel
fuel
secondary
air
fuel +
primary air
fuel
primary air
primary air
primary air
ash
ash
fixed bed combustion bubbling fluidised
(grate furnace)
bed combustion
up to 50 MWth
> 20 MWth
ash
circulating fluidised
bed combustion
> 30 MWth
ash
pulverised fuel
combustion
all sizes
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
Biomass to power applications –
characteristics & combustion
technologies (I)
 Large-scale biomass to power applications
 > 20 MWe power output
 Power generation only
(excess heat is cooled off)
 Net electric efficiency: > 30%
 Combustion technologies:
• Bubbling fluidised bed
combustion (BFBC)
BFBC
CFBC
• Circulating fluidised bed
combustion (CFBC)
• Pulverized fuel combustion
 Power generation technology
• Steam turbine
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
Examples of large-scale power plants
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
Large-scale power plants (I)
 Wilton 10 power plant:
 Location: Middlesborough,
England
 Start of operation: 2007
 Power output: 35 MWe; net electric efficiency (based on NCV): 30%
 Combined heat and power production (currently power only)
 Technology: Bubbling fluidized bed combustion, steam boiler,
(520°C/120 bar) steam turbine
 Fuel demand: 300,000 t (wet basis) such as forest residues, wood
processing residues, waste wood, short rotation coppice
 Fuel logistics: fuel supply by truck & rail, storage capacities for 14
days, fuels are either delivered ready to use or are processed on site
 Investment costs: £64 million
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
Large-scale power plants (II)
 Wilton 10 power plant: process diagram
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
Large-scale power plants (III)
 Steven's Croft biomass power station:
 Location: Lockerbie, Scotland
 Start of operation: 2007
 Power only
 Power output: 44 MWe, net electric efficiency (based on NCV): 29%
 Technology: Bubbling fluidized bed combustion, steam boiler
(537°C/137 bar), steam turbine
 Fuel demand: 480,000 t (wet basis)
 Fuels used: forest wood and agricultural residues, urban wastes and
short rotation coppice
 Fuel logistics: fuel supply by truck, storage capacities for 14 days,
fuels are either delivered ready to use or are processed on site
 Investment costs: £90 million
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
Large-scale power plants (IV)
 Aerial view Steven's Croft biomass power station:
Main round wood storage area
Boiler house
Chipped wood
storage area
Fuel storage (10,000 m³)
Condenser
Fuel processing
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
Large-scale power plants (V)
 Polaniec, Poland
 205 MWe, circulating fluidized bed combustion, steam boiler
(565°C/127 bar), steam turbine
 Power only, net electric efficiency (based on NCV): 36.5%
 Fuel demand 1,110,000 t/a (wood chips and agricultural residues)
 Fuel logistics: fuel supply by ship, truck & rail, fuels are stored
and processed on site
 Simmering, Austria
 17 MWe (CHP mode), bubbling fluidized bed combustion, steam
boiler (520°C/118 bar), steam turbine
 Combined heat and power production, net electric efficiency: 27%,
thermal efficiency: 59%, total efficiency: 86%
 Fuel demand 130,000 t/a (wood chips); fuel supply by ship, fuels
are stored and processed on site
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
Biomass CHP – small-scale
applications
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
Biomass CHP applications –
characteristics & combustion
technologies (I)
 Small-scale biomass CHP applications
 20 - 200 kWe power output
 Combined heat and power generation only (in combination
with process or district heating)
 Net electric efficiency: 5 – 15%
 Thermal efficiency: 70 – 80%
 Overall efficiency: up to 90%
 Combustion technology:
• Fixed bed (grate) combustion
 Power generation technology
• Organic Rankine Cycle (CraftEngine)
CraftEngine
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Biomass CHP applications –
characteristics & combustion
technologies (II)
BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
 Plant layout grate furnace with pressurized hot water boiler
and CraftEngine
Flue gas recirculation
Biomass fuel
Flue gas
Air
Ash
CraftEngine
Feed of pressurized
hot water
Return of pressurized
hot water
Electricity production
Adsorption or absorption chillers
To
chimney
Flue gas
fan
Biomass
combustion
To heat consumer
Buffer
storage
Biomass
Ash discharge
Biomass combustion with pressurized hot water boiler
Low temperature dryers
Heat / cold production
To ash container
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
Correct dimensioning
of a biomass CHP plant
Nominal thermal
power
BM - CHP
Thermal output of the
CHP plant in %
 A minimum of 5,000 full load operating hours is a target for
an economic operation of CHP plants  a correct
dimensioning based on local constraints is important!
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
The role of biomass to power within
the “GREEN BARBADOS” project
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
Basic principles for
green energy production
 Use an efficient mix of renewables
 Biomass
 Solar
 Wind
 Geothermal energy
 Waste
 Utilize the optimisation potential regarding energy savings
and efficiency improvements
 Efficient energy generation
 Efficient energy distribution
 Efficient energy utilization
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
Potential fuel sources for
“GREEN BARBADOS”
 Pellets
 Transport per ship from
North America
 Industrial wood chips
 Local sawmills (if available)
 Transport per ship from
North and South America
 Short rotation coppice
 From local agricultural land
(e.g. former sugar cane
plantations)
 Yield dependent on local conditions (typical yields vary
between 10 and 30 t/ha*a (dry basis))
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
Biomass to power within
“GREEN BARBADOS” (I)
 Biomass to power - large-scale application:
 Centralized power generation
 providing base load power by replacing conventional fossil
fuels (e.g. diesel)
 Continuous operation at full load to minimize power
generating costs
 Biomass fuel supply by ship transport
 Biomass fuel supply may also serve decentralized smallscale CHP applications
 Combination of biomass and solar power possible
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
Biomass to power within
“GREEN BARBADOS” (II)
 Scenario for a large-scale biomass power plant:
 Average power demand Barbados: 120 MWe
 Peak power demand Barbados: 157 MWe
 Base load coverage by biomass power plant: 50 MWe
 Technology: fluidized bed combustion with steam boiler and
steam turbine
 Target net electric efficiency: 35%
 Full load operating hours per year: 8,000 h
 Annual electricity production: 400 GWh (about 40 to 45% of the
annual demand)
 Fuels used: pellets, industrial wood chips, short rotation coppice
 Fuel demand: from 250,000 t/a (wet basis, pellets) to 500,000 t/a
(wet basis, industrial wood chips)
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
Biomass to power within
“GREEN BARBADOS” (III)
 Biomass CHP - small-scale application:
 Decentralized units with combined heat/cold and power
generation
 Operation at sites with rather permanent power and
heat/cold demand providing power and reducing the
electricity demand for chilling/cooling
 The size of the small-scale applications is dependent on the
local heating (e.g. for drying processes) or chilling/cooling
(process cooling, space cooling) demand
 Heat controlled operation:
Heat is the main product and power a valuable by-product
 Buffer tanks for an intermediate heat storage can be
meaningful to avoid load fluctuations
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
Biomass to power within
“GREEN BARBADOS” (IV)
 Scenario for a small-scale biomass CHP plant:
 Power output: 30 kWe, Heat output: 400 kWth
 Technology: fixed bed combustion (grate furnace) with pressurized
hot water boiler and CraftEngine
 Target net electric efficiency: 6 - 8% (based on fuel input NCV),
thermal efficiency: 80 - 82%, overall plant efficiency: 88%
 Full load operating hours per year: 5,000 h
 Annual electricity production: 150 MWhe
 Annual heat production: 2,000 MWhth (flow temperature 81°C, return
temperature 70°C)  potential use for drying or cooling/chilling
processes
 Fuels used: pellets, industrial wood chips, short rotation coppice
 Fuel demand: from 530 t/a (pellets) to 1,000 t/a (industrial wood chips)
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BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
Summary and conclusions
 Biomass is an important renewable energy source with the
highest short- and medium-term application potential
world-wide
 Biomass to power and biomass CHP applications represent
state-of-the-art renewable energy solutions
 Potential fuel sources for “GREEN BARBADOS” are pellets,
industrial wood chips and short rotation coppice
 Two potential application options have been identified:
 Large-scale power plant for national base load power coverage
 Decentralized small-scale CHP plants for power and heat
generation for locations with power and heat/cooling/chilling
demand
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Thank you very much for your attention!
BIOENERGIESYSTEME GmbH
Inffeldgasse 21b, A-8010 Graz
For further information, please visit our website at:
www.bios-bioenergy.at
or send an e-mail to:
office@bios-bioenergy.at
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