Maine’s GHG Inventory, 1990-2000

Maine’s GHG Inventory, Maine’s GHG Inventory, 1990-20001990-2000

Prepared by the Maine DEPPrepared by the Maine DEP

November 6th, 2003November 6th, 2003

What is an Emissions Inventory ?What is an Emissions Inventory ?

Comprehensive list by source, of Comprehensive list by source, of

air pollutant emissionsair pollutant emissions

• Covers a specific geographic areaCovers a specific geographic area

• Over a specific time intervalOver a specific time interval

What is an Emissions Inventory ? What is an Emissions Inventory ? Cont.Cont.

Type of emissions sourcesType of emissions sources

• Point Source - individual sources of Point Source - individual sources of

emissions emissions

• Area Source - aggregate of small sourcesArea Source - aggregate of small sources

• Mobile Source - cars, trucks and othersMobile Source - cars, trucks and others


Approaches to inventoriesApproaches to inventories

• Top Down - Based on national or regional Top Down - Based on national or regional

estimates for similar types of emissions estimates for similar types of emissions

sourcessources

• Bottom Up - Source specific informationBottom Up - Source specific information

Note - Top down inventories are less resource intensive; Note - Top down inventories are less resource intensive;

however the resource savings comes at a cost to the however the resource savings comes at a cost to the

precision of the inventoryprecision of the inventory..


Emission Inventories are Emission Inventories are estimates of estimates of

emissionsemissions

Why do a GHG Emissions Why do a GHG Emissions Inventory ?Inventory ?

Identify sources of GHGsIdentify sources of GHGs

Quantify sources of GHGsQuantify sources of GHGs

Develop strategies to control GHGs Develop strategies to control GHGs

Assess effectiveness of the strategiesAssess effectiveness of the strategies

GHG Emissions Source GHG Emissions Source SectorsSectors

TransportationTransportation• Mobile on-road and non- road emissionsMobile on-road and non- road emissions

Waste Waste • Solid waste disposal (landfills, combustion)Solid waste disposal (landfills, combustion)• Waste water treatment plantsWaste water treatment plants

LUCFLUCF• Land use change and forestry practices Land use change and forestry practices

(may be a net source or sink)(may be a net source or sink)

GHG Source Sectors Cont.GHG Source Sectors Cont.

ResidentialResidential

• Home heatingHome heating

IndustrialIndustrial• Space heating at industrial facilitiesSpace heating at industrial facilities

CommercialCommercial• Heating in retail and office spaceHeating in retail and office space

GHG Source Sectors Cont.GHG Source Sectors Cont.

Industrial ProcessIndustrial Process• Manufacturing process emissions Manufacturing process emissions • Cement and Semi-conductorsCement and Semi-conductors

Electric UtilitiesElectric Utilities• Power plants and Co-generation Power plants and Co-generation

facilitiesfacilities

Agriculture Agriculture • Enteric Fermentation, Manure ManagementEnteric Fermentation, Manure Management• Agriculture Soil ManagementAgriculture Soil Management

Greenhouse GasesGreenhouse Gases

Carbon dioxide (COCarbon dioxide (CO22))

Methane (CHMethane (CH44))

Nitrous oxide (NNitrous oxide (N22O)O)

Hydrofluorocarbons (HFCs)Hydrofluorocarbons (HFCs)

Perfluorocarbons (PFCs)Perfluorocarbons (PFCs)

Sulfur Hexafluoride (SFSulfur Hexafluoride (SF66))

Units of MeasureUnits of Measure

Non-CONon-CO22 gases converted to CO gases converted to CO22 equivalents using agreed Global equivalents using agreed Global Warming Potential (GWP) valuesWarming Potential (GWP) values

Total inventories generally measured in Total inventories generally measured in million metric tons of carbon equivalent million metric tons of carbon equivalent or COor CO22 equivalent -- check units when equivalent -- check units when comparing inventoriescomparing inventories

Guidance Materials for Guidance Materials for InventoriesInventories

Basic ground rules developed and updated by Basic ground rules developed and updated by Intergovernmental Panel on Climate Change Intergovernmental Panel on Climate Change for Annex I parties to FCCCfor Annex I parties to FCCC

EPA sets guidance for U.S. national inventory EPA sets guidance for U.S. national inventory and for states, based on international and for states, based on international practices with modifications where practices with modifications where appropriate for U.S. appropriate for U.S.

Trade Association may supply guidanceTrade Association may supply guidance

Other entities (World Resources Inst. (WRI))Other entities (World Resources Inst. (WRI))

Guidance Materials, cont.Guidance Materials, cont.

Guidance may change periodically Guidance may change periodically • New data becomes available New data becomes available • Scientific understanding of GHGs improvesScientific understanding of GHGs improves• Refinements in emissions factorsRefinements in emissions factors

State GHG Inventory ToolState GHG Inventory Tool

Developed for EPA, by a contractor, to make Developed for EPA, by a contractor, to make

the inventory process less time- and resource-the inventory process less time- and resource-

intensive and to make state inventories more intensive and to make state inventories more

comparable in terms of data and methodscomparable in terms of data and methods

Provides state-specific default data from Provides state-specific default data from

Federal sources in spreadsheet form; states Federal sources in spreadsheet form; states

can use defaults or insert their own datacan use defaults or insert their own data

Default data use represents a Top Down Default data use represents a Top Down

inventory approach.inventory approach.

Uncertainty Associated Uncertainty Associated with Estimating GHG with Estimating GHG EmissionsEmissions

GHGs are rarely measured directly ; GHGs are rarely measured directly ; emissions are more typically calculated emissions are more typically calculated on the basis of emissions factors, or are on the basis of emissions factors, or are inferred on the basis of observed inferred on the basis of observed relationships. relationships.

Precision of input data varies widely Precision of input data varies widely – fuel usage at power plants vs. waste placed in fuel usage at power plants vs. waste placed in

landfills landfills – proprietary processes maybe reported with less proprietary processes maybe reported with less

precisionprecision

ME GHG Emissions, 1990-ME GHG Emissions, 1990-20002000

Gross Emissions Trends GHG 1990 - 2000

24.25

23.54

24.53

25.49

26.75

25.87

26.86

27.25

26.79

24.85

24.62

23.00

23.50

24.00

24.50

25.00

25.50

26.00

26.50

27.00

27.50

1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000

Year

MM

TC

O2

E -

Mil

lio

n M

etr

ic t

on

s o

f C

arb

on

Dio

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e e

qu

iva

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Yearly Totals

ME GHG Emissions, 1990ME GHG Emissions, 1990

1990 GHG Mix

Residential11%

Commercial8%

Electric Utilities7%

Waste6%

Agriculture 2%

Industrial14%

LUCF15%

Transportation36%

Industrial Process1%

Transportation

LUCF

Industrial

Residential

Commercial

Electric Utilities

Waste

Agriculture

Industrial Process

ME GHG Emissions, 2000ME GHG Emissions, 2000

2000 GHG Mix

LUCF19%

Residential16%

Industrial11%

Waste6%



Agriculture 1%

Commercial6%

Transportation34%

Transportation

LUCF

Residential

Industrial

Waste

Commercial

Industrial Process

Electric Utilities

Agriculture

ME GHG Emissions, ME GHG Emissions, revised 2000revised 2000

CO2 emission for 2000 (Utility based on EGRID)

Transportation28%


LUCF15%

Residential14%

Industrial9%

Waste5%

Commercial5%


Agriculture 1%

Transportation

Electric Utilities

LUCF

Residential

Industrial

Waste

Commercial

Industrial Process

Agriculture

ME GHG Emissions, ME GHG Emissions, revised 2000revised 2000

Emissions (MMTCO2E) 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000

Energy 18.455 17.684 18.531 18.374 19.565 18.581 19.421 19.699 19.281 17.332 17.369

CO2 f rom Fossil Fuel Combustion 17.874 17.077 17.892 17.730 18.923 17.941 18.750 19.067 18.719 16.732 16.732

Stationary Combustion 0.268 0.287 0.306 0.306 0.300 0.304 0.339 0.302 0.237 0.273 0.273

Mobile Combustion 0.313 0.320 0.333 0.338 0.342 0.337 0.332 0.330 0.326 0.327 0.319

Coal Mining - - - - - - - - - - -

Natural Gas and Oil Systems - - - - - - - - - - 0.045

I ndustrial Processes 0.200 0.204 0.353 0.435 0.442 0.550 0.597 0.645 0.707 0.725 0.715

Agriculture 0.385 0.391 0.383 0.395 0.388 0.369 0.379 0.374 0.364 0.353 0.343

Enteric Fermentation 0.174 0.177 0.174 0.173 0.174 0.164 0.166 0.164 0.159 0.158 0.154

Manure Management 0.048 0.048 0.048 0.052 0.051 0.050 0.052 0.052 0.053 0.053 0.048

Rice Cultivation - - - - - - - - - - -

Agricultural Soil Management 0.162 0.166 0.162 0.170 0.164 0.155 0.161 0.158 0.152 0.143 0.140

Burning of Agricultural Crop Waste - - - - - - - - - - 0.000

LUCF 3.740 3.756 3.754 4.558 4.568 4.572 4.580 4.584 4.583 4.585 4.585

Waste 1.470 1.504 1.512 1.732 1.790 1.799 1.881 1.949 1.855 1.853 1.609

Municipal Solid Waste 1.373 1.406 1.414 1.633 1.690 1.700 1.781 1.849 1.755 1.752 1.505

Wastewater 0.097 0.098 0.099 0.099 0.100 0.099 0.100 0.100 0.101 0.102 0.104

Gross Emissions 24.249 23.539 24.533 25.493 26.754 25.871 26.859 27.251 26.791 24.849 24.620

Sinks - - - - - - - - - - -

Net Emissions 24.249 23.539 24.533 25.493 26.754 25.871 26.859 27.251 26.791 24.849 24.620

Summary of GHG Emissions by Sector in Maine

(MMTCO2E)Return to Control

Sheet

Go to Summary by

Gas

Documents

Maine’s GHG Inventory, 1990-2000