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Landfill Gas to Energy

Clark WiedetzGeneral ManagerAlternative Energy678-427-0150

Program Overview

Division: Energy & Environmental SolutionsDate: December 12, 2007

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Executive Summary

• The landfill gas (lfg) project marketplace is expanding at record-level proportions.

• The Landfill Gas Methane Outreach Program (LMOP) estimates that 50 projects will become operational in the next 24 months.

• The price of fuel has increased 300% in the last 4 years, thus exceeding the cost to convert lfg into a usable form of utility

• Increased environmental regulations for landfills are being mandated

• Lfg has been designated as a renewable energy source by the Federal Government and in 24 States with Renewable Portfolio Standards, thus making lfg projects eligible for a number of incentives and tax credits.

For internal use only / Copyright © Siemens AG 2006. All rights reserved.

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Landfill Gas

Landfill Gas

Is about 50% CH4 (Methane) Is about 50% CO2 Contains other trace gases & elements Is naturally created by the decomposition of garbage Has a very high greenhouse effect Has a heating content of about 1/4 that of natural gas

Methane creates roughly 20 times the greenhouse effect of CO2

… unless you burn it!

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How can we use these fuels?

Direct Use Project Gas is piped to a boiler, where it is combusted to make heat or steam.

Electric Generation Project Gas is piped to a nearby electric generator, where it is combusted to

make electricity.

Pipeline Injection Project CO content is minimized. Gas is compressed, then injected into a natural

gas pipeline.

For internal use only / Copyright © Siemens AG 2006. All rights reserved.

Landfill Gas - to - Direct Use Process

EXISTING LFG FLARE

Point of

EXTG KNOCKOUT TANK Fuel Gas Delivery

Leachate

Raw Landfill EXISTING LEACHATE Conditioned Gas IN TRANSFER PIPELINE Gas OUT

TO HOLDING POND

Transport Piping

Point of Delivery (HDPE underground) (S/S above ground)

Integrated Quantity & Quality Combustion Controls Metering

NG Fuel IN Fuel Oil IN

LFG BLOWER

LFG DRYING/TREATMENT

STATION

GAS F I E L D

EXISTING LFG BLOWER

EXISTING BOILER w/ EXISTING BURNER andNEW Medium-Btu BURNER

(to supplant fossil fuel)

NEW Med-Btu

Fossil Fuel Burner

Direct Use

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Three Rivers SWA/ Kimberly-Clark

“Landfill gas to be used for diapers” from Waste News

Installed collection system and flare

Conditioned, if necessary, to remove challenging trace gases

Compression system

17 miles of pipe

Boiler retrofit to accept and combust landfill gas

$10MM project

Carbon credits help project economics

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Customer Deal Structure Example (Three Rivers SWA)

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Electric Generation Project

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Electric Generation

For an Electric Generation Project, the gas is also

Collected, compressed and conditioned, if necessary.

Used as fuel for reciprocating engines, fuel cells, microturbines

Larger projects can send renewable power to utilities (thus fulfilling RPS requirements)

Renewable energy credits (RECs) and possibly Production Tax Credits (PTCs) help project economics

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Landfill Gas Project Developers

Siemens

DTE Biomass

Fortistar

Ameresco

Energy Services Group

Waste Management

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Questions?