powerpoint presentationswanacal.com/downloads/2019wrstrackbpresentations/4b...title powerpoint...

www.jacobs.com | worldwide

Estimating GHG Impacts

for Residential Waste

Management Programs

Presented by Doug Huxley

Climate Change Practice Leader

At the SWANA Western

Regional Symposium

April 9, 2019

2

Disclaimer

The material in this presentation has been prepared by Jacobs Engineering Group

Copyright and other intellectual property rights in this presentation vest exclusively with Jacobs. Apart from any use

permitted under applicable copyright legislation, no part of this work may in any form or by any means (electronic,

graphic, mechanical, photocopying recording or otherwise) be reproduced, copied, stored in a retrieval system or

transmitted without prior permission.

© Copyright

February 27, 2019

Jacobs Engineering Group. All rights reserved.

Image by Markus Distelrath from Pixabay

3

Thousands of cities and

counties have pledged action

Aspirational targets,

often with no solid plan

Responsibilities with

multiple departments

Uncertainty with limited

understanding of benefits,

costs, and risks

Solid waste GHG reductions

mandated in California

Challenges facing local governments

We Are Still In

America’s Pledge

Global Covenant of Mayors

California SB1383

4

80% Targets Require Action Across All Sectors

To view the full documents, visit https://ghgprotocol.org/public-sector-protocol-0

5

Need common platform for

analysis of benefits

Typically compares against

zero, versus true baseline

Scope 1, 2, and 3 focus means

secondary impacts often

ignored

Annual focus, vs. solid waste

life cycle

Only used in corporate and

muni protocols

Limitations of Corporate Accounting for evaluating mitigation options

6

Project based accounting approach

Figure from GHG Protocol Project Accounting Standard, P. 13

Baseline scenario: absolutely required for meaningful evaluation of change

Evaluate all impacted GHG emission sources, regardless of ownership and control

Yearly updates are usually to include updated information for life of project, not to indicate annual performance

7

Project based accounting approach Key Concepts

1

2

3

8

Example GHG Profile Landfill Future Growth

Profile shows the change at

this landfill but is incomplete

picture of city-wide baseline.

9

Example GHG Profile Food Waste Diversion

Profile includes landfill and

digestion benefits and is

more consistent with

city-wide baseline since it

incorporates growth.

10

Example GHG Profile City-wide waste management

Profile includes city-wide

emissions, but evaluation

of LFGTE and recycling

benefits still requires

evaluation of impacts

outside city Scope 1, 2,

and 3 footprint

Baseline is not zero

Baseline is dynamic

GHG emission increases / decreases vary by year

Boundary definition must match the question at hand

11

Example GHG Profile Concepts

1

2

3

4

12

Existing tools for solid waste GHG analyses

WARM (USEPA Waste Reduction Model)

– EPA model built in 1998, now V14

– Life cycle GHG comparative evaluation

– Good tool for general comparison of alternatives, however:

• Hard to customize for multiple transportation steps, alternative fuels, capture rates, etc.

• Only one option for use of biogas, displacement of grid power

• Black box makes it hard to understand where benefits or emissions occur

• Discrepancies exist between guidance and model

LandGem

– EPA model and accepted standard for landfill gas production

– Good tool for landfill gas flows, poor tool for GHG impacts of alternatives

Landfill

Dry digestion

Wet digestion

Wet digestion –

headworks

Composting

Chip & grind

Recycling

Transportation

13

GHG Calculator - Processes Included Flow diagram #3 of 5 from LASAN model

14

GHG Calculator – transparent and customizable

15

Ability to specify haul

distances including

intermediates and residuals

Consideration of

CNG and RNG

Functionality for food waste to

WWTP headworks

Ability to specify average gas

collection efficiency

Definition of benefits of landfill

& digester biogas use besides

grid electricity displacement

Good basis for demonstration

of SB1383 emissions

reductions

GHG Calculator

Transportation is small impact compared to other

categories

CNG fuel a relatively small difference vs. diesel on

a life cycle or tailpipe basis

Benefits of alternatives highly sensitive to gas

collection efficiency and landfill moisture

Food waste - big benefit to digestion vs. landfill

– Gas capture higher in digester

– Low landfill carbon storage

Yard Waste - small benefit to digestion vs. landfill

– Slower decay rate, less landfill gas

– Higher carbon storage

Soil and landfill carbon storage are important in

considering reduced biogenic emissions

Recycling benefits dwarf other categories (if

recyclables are really recycled!)

16

Lessons learned - examples

Reduction targets of 80-100% require action

across all sectors

Actions must be evaluated against future baseline

to be meaningful

WARM is useful in understanding life cycle

impacts, but limited

Customized GHG calculator allows a city-specific,

comprehensive planning view

GHG impacts that occur outside system

boundaries (e.g., LFGTE) are accounted for as

“negative” emissions

17

Summary

Doug Huxley Golan Kedan 1.720.286.5503 1.206.234.6524

doug.huxley@jacobs.com golan.kedan@jacobs.com

18

Thank You

Thanks to: Jeremy Pathmanabhan, and his

team at LA Sanitation & Environment

jeremy.pathmanabhan@lacity.org