It has been proven that carbon dioxide emissions (greenhouse gases GHGs) absorb energy, slowing or preventing the loss of heat to space. In this way, GHGs act like a blanket, making Earth warmer than it would otherwise be. This process is commonly known as the “greenhouse effect”. How much GHGs are actually emitted from Ontario plants.

1. COCO22 Emission Rate per MWh of EnergyEmission Rate per MWh of Energy
Generated from Coal-Fired PlantsGenerated from Coal-Fired Plants
© Copyright 2008 David Palmer

2. CoalCoal
Coal is one type ofCoal is one type of
fossil fuelfossil fuel
It is the largest singleIt is the largest single
source of:source of:
fuel for thefuel for the
generation ofgeneration of
electricityelectricity
carbon dioxidecarbon dioxide
emissionsemissions
© Copyright 2008 David Palmer

3. Complete Combustion of CoalComplete Combustion of Coal
OH
y
xCOO
y
xHC yx 222 )
2
()
4
( +⇒++
WaterCOheatoxygenfuel 2 ++⇒+
© Copyright 2008 David Palmer

4. The Energy Density of CoalThe Energy Density of Coal
Energy density ‘Q’ is also referred to fuelEnergy density ‘Q’ is also referred to fuel
content or heating ability (MJ / kg)content or heating ability (MJ / kg)
1000
93)
8
(1442337 S
O
HC
Q
+−+
=
where; C is the mass percent of carbon,
H is the mass percent of hydrogen,
O is the mass percent of oxygen, and
S is the mass percent of sulfur in the coal
The energy density of coal is roughly 24 kg
MJ
© Copyright 2008 David Palmer

5. Various Types of CoalVarious Types of Coal
ASTM classASTM class ASTM groupASTM group MJ/kgMJ/kg
LigniteLignite Lignite ALignite A <14.6<14.6
Lignite BLignite B 14.6-19.314.6-19.3
Sub-bituminousSub-bituminous Sub-bituminous CSub-bituminous C 19.3-22.119.3-22.1
Sub-bituminous BSub-bituminous B 22.1-24.422.1-24.4
Sub-bituminous ASub-bituminous A 24.4-26.724.4-26.7
High volatile CHigh volatile C 24.4-30.224.4-30.2
BituminousBituminous High Volatile BHigh Volatile B 30.2-32.530.2-32.5
High Volatile AHigh Volatile A >32.5>32.5
Medium volatileMedium volatile >32.5>32.5
Low volatileLow volatile >32.5>32.5
AnthraciteAnthracite Semi-anthrciteSemi-anthrcite >32.5>32.5
AnthraciteAnthracite >32.5>32.5
Meta-anthraciteMeta-anthracite >32.5>32.5
© Copyright 2008 David Palmer

6. As mentioned earlier the energy density ofAs mentioned earlier the energy density of
coal is 24 , this converts tocoal is 24 , this converts to
from,from,
Energy Density of CoalEnergy Density of Coal
kg
hkW⋅
kg
MJ
kg
hkW
MW
kWh
sJ
Ws
kg
MJ ⋅
=×××× 67.61000
min6060
min
24
© Copyright 2008 David Palmer

7. Thermodynamic EfficiencyThermodynamic Efficiency
of Coal-Fired Plantsof Coal-Fired Plants
Typical thermodynamic efficiency of coalTypical thermodynamic efficiency of coal
plants is about 30%.plants is about 30%.
Coal has 6.67 kW·h of energy perCoal has 6.67 kW·h of energy per
kilogram and approximately 30% cankilogram and approximately 30% can
successfully be turned into electricity – thesuccessfully be turned into electricity – the
remaining energy is heat waste.remaining energy is heat waste.
Coal power plants obtain approximatelyCoal power plants obtain approximately
2.0 kW·h per kg of burned coal.2.0 kW·h per kg of burned coal.
© Copyright 2008 David Palmer

8. Energy Consumption ExampleEnergy Consumption Example
As an example, running one 100 watt light bulb forAs an example, running one 100 watt light bulb for
one year requires 876 kW·h.one year requires 876 kW·h.
(100 W × 24 h/day × 365 {days in a year}(100 W × 24 h/day × 365 {days in a year}
= 876000 W·h= 876000 W·h
= 876 kW·h= 876 kW·h
Converting this power usage into physical coalConverting this power usage into physical coal
consumption:consumption:
coaloflbs966coalofkg438
kghkW2.0
hkW876
==
⋅
⋅
© Copyright 2008 David Palmer

9. COCO22 ProductionProduction
Coal is at least 50% carbon (by mass), then 1 kgCoal is at least 50% carbon (by mass), then 1 kg
of coal contains at least 0.5 kg of carbon.of coal contains at least 0.5 kg of carbon.
Carbon has an atomic weight of 12 kg / kmol,Carbon has an atomic weight of 12 kg / kmol,
where 1 mol is equal to NA (Avogardo’swhere 1 mol is equal to NA (Avogardo’s
Number)Number)
Therefore, 0.5 kg of carbon is,Therefore, 0.5 kg of carbon is,
Carbon reacts with oxygen during combustion,Carbon reacts with oxygen during combustion,
producing carbon dioxide, COproducing carbon dioxide, CO22, which has an, which has an
atomic weight of (12 + 16 × 2 = 44 kg / kmol)atomic weight of (12 + 16 × 2 = 44 kg / kmol)
kmol
24
1
12
5.0
=
⋅ kmolkg
kg
© Copyright 2008 David Palmer

10. Kilograms of COKilograms of CO22 ProducedProduced
per Kilogram of Coalper Kilogram of Coal
As mentioned earlier,As mentioned earlier,
The same number of ‘x’carbon atoms are found in coal (CxHy)The same number of ‘x’carbon atoms are found in coal (CxHy)
before combustion as seen in carbon dioxide CObefore combustion as seen in carbon dioxide CO22 afterafter
combustion then,combustion then,
1 / 24 kmol of CO1 / 24 kmol of CO22 is produced from the 1 / 24 kmol present inis produced from the 1 / 24 kmol present in
every kilogram of coal, which weighs approximately,every kilogram of coal, which weighs approximately,
OH
y
xCOO
y
xHC yx 222 )
2
()
4
( +⇒++
kg1.83
kmol
kg44
kmol
24
1
≈⋅
© Copyright 2008 David Palmer

11. Carbon Cost of EnergyCarbon Cost of Energy
with the use of Coal Powerwith the use of Coal Power
Variables:Variables:
Thermodynamic efficiency of coal fired plant = 30%Thermodynamic efficiency of coal fired plant = 30%
Energy density = 6.67 kW·h of energy per kilogram of coalEnergy density = 6.67 kW·h of energy per kilogram of coal
Energy produced = 2.0 kW·h/kg (coal)Energy produced = 2.0 kW·h/kg (coal)
As calculated earlier,As calculated earlier,
1 kg of coal produces roughly 1.83 kg C01 kg of coal produces roughly 1.83 kg C022, then using electricity from coal, then using electricity from coal
produces COproduces CO22 at a rate of,at a rate of,
or,or,
hkW
kg
915.0
kghkW2.0
kg1.83
⋅
=
⋅
MJ
kg
254.0
MJ
kJ
1000
kJ
kWs
60s
min
60min
h
hkW
kg
915.0 =××××
⋅
© Copyright 2008 David Palmer

12. Comparison withComparison with
U.S Energy ReportU.S Energy Report
This estimate compares with the U.S Energy InformationThis estimate compares with the U.S Energy Information
Agency’s Report on COAgency’s Report on CO22 emissions for energyemissions for energy
generation, which quotes a production rate ofgeneration, which quotes a production rate of
By comparison COBy comparison CO22 generation from oil wasgeneration from oil was
and natural gas wasand natural gas was
hkW
kg
950.0
⋅
hkW
kg
0.890
⋅
hkW
kg
600.0
⋅
© Copyright 2008 David Palmer

13. SummarySummary
Using electricity from coal produces COUsing electricity from coal produces CO22
at a rate of, , which is also equal to,at a rate of, , which is also equal to,
hkW
kg
915.0
⋅
hMW
kg
915
MW
kW
1000
hkW
kg
915.0
⋅
=×
⋅
© Copyright 2008 David Palmer

14. Ontario’s Five Coal-Fired PlantsOntario’s Five Coal-Fired Plants
Lambton
Nanticoke
Atikokan
Thunder Bay
Lennox
© Copyright 2008 David Palmer

15. Ontario’s Lambton Coal-Fired PlantOntario’s Lambton Coal-Fired Plant
The following table shows the COThe following table shows the CO22 emission rates, in kilograms peremission rates, in kilograms per
megawatt-hour (kg / MWh) of each of the Lambton Generatingmegawatt-hour (kg / MWh) of each of the Lambton Generating
Station’s coal-fired boilers, (results from 2005).Station’s coal-fired boilers, (results from 2005).
Emission
Rates
kg / MWh
Lambton
Unit 1
Lambton
Unit 2
Lambton
Unit 3
Lambton
Unit 4
Carbon
Dioxide
CO2
927.80 927.35 926.87 926.57
© Copyright 2008 David Palmer

16. Resistance and HeatingResistance and Heating
in the Power Linesin the Power Lines
One should also take into account transmission andOne should also take into account transmission and
distribution losses caused by resistance and heating indistribution losses caused by resistance and heating in
the power lines. Which is in the order of 5–10%,the power lines. Which is in the order of 5–10%,
depending on the distance from the power station anddepending on the distance from the power station and
other factors.other factors.
If this was taken into account our earlier calculation ofIf this was taken into account our earlier calculation of
would equal,would equal,
hkW
kg
915.0
⋅
hkW
kg
960.005.1
hkW
kg
915.0
⋅
=×
⋅
© Copyright 2008 David Palmer

17. Other Types of COOther Types of CO22 ProductionProduction
Steel-makingSteel-making
1.97 ton CO1.97 ton CO22 / ton of steel produced/ ton of steel produced
Cement makingCement making
0.87 to 0.97 ton CO0.87 to 0.97 ton CO22 / ton of cement produced/ ton of cement produced
AutomobliesAutomoblies
165 g CO165 g CO22 / km driven or,/ km driven or,
2.5 kg CO2.5 kg CO22 / Litre of gasoline consumed/ Litre of gasoline consumed
© Copyright 2008 David Palmer