“Exploring a Water/Energy Trade-off in

Regional Sourcing of Livestock Feed Crops”

Martin Heller

October 22, 2015

(Heller & Keoleian, Environ. Sci. Technol. 2011, 45, 10619–10626)

LIFE CYCLE ASSESSMENT: the “compilation and evaluation of the inputs

and outputs and the potential environmental impacts of a product system

throughout its life cycle” (ISO 14040)

Impact Assessment Methods

= inventory flows

LCA of large-scale vertically integrated

organic dairy

• 6 farms in CO and in TX – Over 20,000 milking cows

• Ultra-pasteurization (UP) milk plant in CO – Produces over 22 million gallons of milk annually

• Largest provider of U.S. private label organic milk

• 3 successive UM SNRE Master’s Projects

LCA of large-scale vertically integrated

organic dairy

“As a demonstration of our steadfast commitment to

corporate citizenship, we have developed our first-ever

Corporate Citizenship Report. This report contains data on

our comprehensive life cycle assessment (LCA) for energy

use, Greenhouse Gas (GHG) emissions, water use, landfill

waste and recycling programs. We started this work in

2008 with the University of Michigan’s School of Natural

Resources and Environment. Each year, for three years,

groups of graduate students came out to Colorado to study

our facilities and gather data to complete the first ever LCA

of a large-scale integrated

organic dairy company.”

Marc Peperzak, Chairman & CEO

in Introduction to Corporate Citizenship Report

Dairies in water stressed regions

AOD farm

Where is the trade-off between

transportation energy and water use

in supplying feed?

Inventory varies: corn irrigation

0

200

400

600

800

1000

1200

UT

AZ

AK

WA

OR

CA

MT

WY

NV

NM CO AR TX ID KS

OK

NE

GA

WV FL

L co

nsu

med

/ k

g D

M C

orn

gra

in (s

tate

)

Source: USDA Farm and Ranch Irrigation Survey (FRIS) (1998-2008 avg.)

Wa

ter

co

nsu

me

d fo

r co

rn p

rod

uctio

n

(L / k

g D

M)

Water Stress Index (WSI) represents

competition for water, as a function of use

and availability

water consumed (blue water) /

water availability

Impact varies: water stress

Pfister et al., 2009, ES&T

water in competition

due to corn

L consumed /kg corn Water Stress Index (L in comp / L cons.)

Water in competition (impact) = consumption x

stress

Data sources

• USDA NASS 2008 Farm and Ranch Irrigation Survey – Irrigation rates by crop and by state

• Combined with acres irrigated and total crop production (USDA census) state-level “irrigation intensity” per kg harvested crop

– Irrigation energy expenses by fuel type • Combined with fuel costs (EIA) pumping energy per kg

harvested crop

• Transportation energy per kg – Rough distance: center of producer state to hypothetical

farms in Kersey, CO and Rosendale, WI (Google Maps)

– LC energy demand for diesel truck or rail transport (Franklin Assoc.)

Corn Grain:

water use impact vs. transport

0

100

200

300

400

500

600

700

800

900

1,000

0 0.5 1 1.5 2 2.5 3 3.5 4

wat

er

in c

om

pe

titi

on

(L

eq

./kg

)

energy of transport to Kersey, CO (MJ/kg)

UT

NE

FL

CA

AZ

CO

KS

WY

NM

TX

OR

MT

SD IN IL

MN

Damage to Water Resources (from Pfister et al., 2009 Environ. Sci. Technol.)

 

water stress =WTA =total annual freshwater withdrawals

hydrological availability

fraction of feshwater consumption

that contributes to depletion= Fdepletion =

WTA-1

WTA

0

ì

íï

îï

for WTA>1

for WTA £1

• Backup-technology concept: “surplus energy” to make the resource available in the future – Energy of desalination

– Theoretical indicator to make water use comparable to other types of resource use

Water stress impacts outweigh transport.

Corn grain delivered to Kersey, CO

Energy for fertilizer is important,

but does not impart a clear trend to the ranking

Corn grain delivered to Kersey, CO

Corn grain delivered to Kersey, CO by RAIL

Actual transport is likely a blend of rail and road

Transport by rail makes water use impacts even more relevant

Transport per kg more important: favors local production

Corn silage delivered to Kersey, CO

Alfalfa hay delivered to Kersey, CO

0

1

2

3

4

5

6

7

8

9

10

Wisconsin

Illinois

Iowa

Indiana

Minnesota

Michigan

Ohio

Missouri

Kentucky

SouthDakota

Tennessee

NorthDakota

Pen

nsylvania

Arkansas

Virginia

Maryland

New

York

NorthCarolina

Mississippi

Alabam

a

SouthCarolina

New

Jersey

Neb

raska

Louisiana

Delaw

are

Montana

Geo

rgia

Oklahoma

Kansas

Florida

Texas

Colorado

Wyoming

Oregon

New

Mexico

California

Utah

Arizona

MJ/kg

CornGraindeliveredtoRosendale,WI

energyofdesalina on

irriga onpumpingenergy

transporta onenergy

Low irrigation needs; not water stressed; favors local production

Spatial LCA:

Feeds & production across regions in the dairy context

Andrew Henderson, Anne Asselin, Martin

Heller, Olivier Jolliet

Work supported by Dairy Research Institute

water in competition

due to corn

L consumed /kg corn Water Stress Index (L in comp / L cons.)

Water in competition (impact) = consumption x

stress

Water in competition

L_eq / kg state corn grain Weight by US corn grain

production:

mainly in the corn belt!

Corn water stress at the national level

Contribution to

national corn grain

impact

From feed → state milk → national milk

Corn grain

Corn silage

Alfalfa hay

Alfalfa silage

Soybean

S. meal

Grass hay

Grass silage

DDGS

(wet & dry)

Pasture

On-farm

activities

kg milk

produced

in state i

rations in

state i

kg

“national”

milk

kg feed

produced

in states j

Milk water stress at national level

CA

AZ

NM

IDTX

WA

CO

UT

ORKS

NV

NE

OK

SD

NYFL

PA

ND

WY

MT

MOMD WI VAAR

25 Others

0 20 40 60 80 100

0

100

200

300

400

500

600

700

L eq

. in

co

mp

etit

ion

(as

Blu

e w

ater

) /

kg

FPC

M (

stat

e)

Milk Production %

Sources: USDA Ag. Census (2007), FRIS

Wa

ter

str

ess fro

m flu

id m

ilk

(L e

q / k

g m

ilk)

NNLSC: corn grain P emission

What happens to the P once it’s

emitted?

Helmes, Henderson, et al., 2012

Looking at different (water) impacts

26

Martin Heller

mcheller@umich.edu

Thank you!