Long-term Strategies for Energy Utilities

Long-term Strategies for Energy Utilities

WSWC – WGA Water/Energy WorkshopApril 2, 2013

2

Water/Energy Nexus – Colorado Context Self-supplied Industry

Thermoelectric generation (~ 50%)

Snowmaking Sand/Gravel Other large industry

Source: Colorado Water Conservation Board, Statewide Water Supply Initiative, Denver Water

90%

Agriculture

8%

Municipal

Self-supplied Industry

2004

2%

82%

Agriculture

15%

Municipal

Self-Supplied Industry

2050

3%

Avg. residential electric demand – 9.3 gallons per day, <6% Denver Water daily per capita water use in 2011.

3

Water Supply Strategy

Supply Diversity Direct-flow/Storage Self-supplied/contract supply Native basin/trans-basin Recycled wastewater

Supply Integration/Flexibility Engagement

4

Drought Resilience thru Cooperative Agreements

Municipal Agreements Contract supplies Trades “Unique” arrangements

Agriculture Agreements Interruptible Supply Recharge Credits

5

DENVER

LONGMONT

GREELEY STERLING

South PlatteP

oudre

St. V

rain

Clear C

reek

Northern Water

Denver Water

Contract

Ag

GLENWOOD SPRINGS

Ag

Hydro

Storage

Storage

6

Water Stewardship Plant process improvement and reuse opportunities

Process wastewater for lime scrubbing Process wastewater for bottom ash removal Increased cooling tower cycles

Technology Combined-cycle gas generation Hybrid cooling Recycled wastewater Renewables Demand-side management

7

Water Usage at PSCo Generating StationsAnnual Water Consumption vs. System Generation

0

10,000

20,000

30,000

40,000

50,000

60,000

2005 2006 2007 2008 2009 2010 2011

An

nu

al W

ater

Co

nsu

mp

tio

n (

acre

-fee

t)

0

5

10

15

20

25

30

35

40

Gen

erat

ion

(M

illi

on

MW

h)

Annual Water Use Annual Generation

8

Future Trends and Water Use Impacts

Gas and combined cycle generation Renewables Emission controls Carbon capture