Michigan WEA, 2013 Conference

June 24, 2013

Peter V. Cavagnaro, P.E., BCEE

Johnson Controls, Inc.

Andrew T. Cronberg, P.E.

City of Fort Worth

Alan Bush, P.E., BCEE

AECOM

Steam Powered Energy

Conservation at

Fort Worth’s Village Creek

WRF

First Construction 1950’s

Qdesign = 166 MGD

Qaverage = 105 MGD

Single Stage A/S w Nitrification

Anaerobic Digestion of Wastewater Solids

Village Creek

Wastewater Reclamation Facility

The Project

The project was delivered using the Energy Performance

Contracting (PC) model

Energy savings funded all improvements identified in this

project

Johnson Controls was the Energy Services Company

(ESCO) for the project

Engineering provided by AECOM, Freese & Nichols, Vic

Weir Consulting, and CDM Smith

3

Project Cost $35 million

Annual Utility Savings $2.56 million

Annual O&M Impacts $0.24 million

Total Annual Benefits $2.80 million

Simple Payback 12.4 years

4

Costs & Benefits

Project Drivers in 2007

• City Wide Effort to Comply with State Legislation

• SB12 (2007) renewed in 2011 via SB898

Extended the SB5 Goal of reducing annual electricity

consumption by 5% for 6 more years, from 2007-2012

“Cost-Effective” Electricity-Based Energy-Efficiency

Measures

Legislation was for air quality improvements

• State Energy Conservation Office (SECO)

Annual Reporting Requirement continues, with 2007

as the Baseline

5

Project Drivers

• A list of projects competing for limited capital

dollars

• Control of operating budget

• The Water Department represented 47% of the

City’s energy expenditures

6

City of Fort Worth PC to Date

Reducing electric consumption 37% in over 100

City facilities $93 million in total savings guaranteed over the

contract term Secured approx. $2 million in utility rebates

7

Department Project Cost

Transportation & Public Works (6 Phases) $34 million

Water (Village Creek WRF) $35 million

Total $69 million

Village Creek Electric Utility

In FY 2008 the City purchased $3.4M for electricity

at Village Creek

Total Demand averaged 7 to 8 MW

• Aeration Blowers

• Primary Effluent Pumps

• Other pumps & Odor Control

Aeration Blowers the main consumer

• Three to four blowers operated at a time

• 1 - 2250 HP

• 2 to 3 - 1,000 HP

… a Net Zero Energy

Village Creek Facility!

Goal

9

1 - Turn off electric motor blowers

10

Pre-project: 2-3 @ 1000 HP + 1 @ 2200 HP

2 – Reduce flaring of digester gas

11

3 – Recover Gas Turbine Waste Heat

12

13

Journey to Net Zero began in the 1960’s

Digester Gas fueled Engine Blowers & Generators

Some heat recovery for anaerobic digesters

Photo courtesy of Vic Weir Consulting, Inc.

In FY02, the City’s wastewater plant began utilizing a

biogas-fired turbine-generator system

and continued in 2002

Provided

about 50%

the

electricity

needs

14

15 15

Journey to Net Zero Energy,

Phase III

FIM #3A: Codigestion

FIM #4: SCADA System

FIM #6E: HVAC

Improvements FIM #6D:

Pump Operation

Improvements

FIM #6H:

Power

Factor

Correction

FIM #1:

Aeration Diffusers

FIM #5: Anoxic Zones FIM #6A: Aeration

Control Improvements

FIM #2: Heat

Recovery

FIM #3B:

Linear Motion

Mixers

Dedicated facility:

Truck unloading pad

30,000 gal mix tank

Two 8,000 gal batch tanks

Recirculation, transfer and feed

pumps (six total)

PLC control feeds each digester

once/hour

Receiving up to 9 x 6,000 gal

trucks / day

VCWRF Co-Digestion System

16

HYDRO DISK AT MID DEPTH

17

Anaerobic Digestion Improvements

Type: Linear Motion Mixers

No: Six (6) digesters - One (1) mixer per digester

Power: 10 HP per mixer

Hydro Disk: 7-ft diameter, 18-in travel, 30 cycles per min

18-inch vertical travel

7-ft diam

90-ft diam digester

Linear Motion Mixer

18

LMM Drive

Scotch-yoke & cam

mechanism

Heat Recovery Steam Generator

(HRSG) on Turbine Exhaust

generates steam

19

Waste Heat Recovery

The duct burner uses digester

gas to boost the temperature of

the turbine exhaust. The higher

temperature is needed to

produce enough steam to power

two steam turbines

Waste Heat Recovery

Duct Burner

Steam Turbine Powered Blowers

20

2 unused 1200 HP 31,000 cfm blowers

Rehab’d and equipped with steam turbine drivers

Aeration Infrastructure renewed

New 9-in membrane diffusers

21

PTFE coating

Include a 10-year

manufacturer

material warranty

Anoxic Zones & Nitrate Rich Recycle

22

SCADA System Replacement

Project included the replacement of the existing Johnson

Yokogawa SCADA system with a new Emerson Ovation

SCADA Distributed Control System

23

24

ANAEROBIC DIGESTERS

GAS TURBINE

DRIVEN

GENERATORS

SOLIDS TO

DEWATERING

HEAT RECOVERY

UNIT

UNUSED BLOWERS

HEX WASTE HEAT FROM

TURBINE EXHAUST

HEATS DIGESTERS

2250

MOTOR DRIVEN

BLOWERS

1000

1000

1000

AERATION SYSTEM

OVER 20 YEARS OLD

SCADA SYSTEM OVER

20 YEARS OLD

Fitting the

pieces together

25

ANAEROBIC DIGESTERS

GAS TURBINE

DRIVEN

GENERATORS

SOLIDS TO

DEWATERING

HEAT RECOVERY

UNIT

UNUSED BLOWERS

HEX WASTE HEAT FROM

TURBINE EXHAUST

HEATS DIGESTERS

2250

MOTOR DRIVEN

BLOWERS

1000

1000

1000

AERATION BASINS

DIFFUSERS REPLACED

ANOXIC ZONES ADDED

NEW SCADA SYSTEM

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ANAEROBIC DIGESTERS

CLEANED & ENHANCED

MIXING

ADDITIONAL DG

TO OPERATE

EXISTING GAS

TURBINE DRIVEN

GENERATORS

REDUCTION IN

SOLIDS TO

DEWATERING

HEAT RECOVERY

STEAM GENERATOR

1 - STEAM TURBINE

DRIVEN BLOWER

CONDENSATE

RETURN

HEX WASTE HEAT FROM

CONDENSER HEATS

DIGESTERS

2250

MOTOR DRIVEN

BLOWERS

1000

1000

1000

NEW SCADA SYSTEM

AERATION BASINS

DIFFUSERS REPLACED

ANOXIC ZONES ADDED

27

HIGH

STRENGTH

WASTE

RECEIVING

ANAEROBIC DIGESTERS

CLEANED & ENHANCED

MIXING

ADDITIONAL DG

TO OPERATE

EXISTING GAS

TURBINE DRIVEN

GENERATORS

REDUCTION IN

SOLIDS TO

DEWATERING

ADDITIONAL DG

TO OPERATE

DUCT BURNER

HEAT RECOVERY

STEAM GENERATOR

2 - STEAM TURBINE

DRIVEN BLOWERS

CONDENSATE

RETURN

HEX WASTE HEAT FROM

CONDENSERS HEATS

DIGESTERS

2250

MOTOR DRIVEN

BLOWERS

1000

1000

1000

NEW SCADA SYSTEM

AERATION BASINS

DIFFUSERS REPLACED

ANOXIC ZONES ADDED

$0

$50,000

$100,000

$150,000

$200,000

$250,000

$300,000

$350,000

$400,000

$450,000

$500,000

0

1,000,000

2,000,000

3,000,000

4,000,000

5,000,000

6,000,000

7,000,000

8,000,000

9,000,000

CO

NS

UM

PT

ION

(K

WH

)

TOTAL PURCHASED (kWh) TOTAL GENERATED DIESEL ENGINE GENERATORS

TOTAL GENERATED (TG1 + TG2) SAVINGS

Performance to Date

Electric Consumption (1995-2013)

Acknowledgements

Fort Worth Water Department

Sebastian Fichera, REM

Assistant Water Director

Madelene Rafalko, P.E.

Senior Professional Engineer

Gary LaGassey

Lead Operator

Ana Pena, Ph.D., P.E.

Jerry Pressley

Luke Matus, I&C

Jake Pena, I&C

Ron Carlson, P.E.

Johnson Controls Team

Harry Romine, P.E., C.E.M.

Account Executive

Dennis Gallagher

Construction Manager

Sarah Phillips, P.E.

Project Development Engineer

Velton Ellis

Construction Superintendent

Vic Weir Consulting, Inc.

Vic Weir, P.E.

Freese and Nichols, Inc.

Ted Gay, P.E.

Leonard Ripley, Ph.D., P.E.

Clay Rahn, P.E.

AECOM

Randy Wodrich

Gary Breitwisch, P.E.

The men and women who

constructed and who operate

the facilities.

CDM Smith

Dean Gorell

Nate Mogaru

Thank you

Peter V. Cavagnaro, P.E., BCEE

Project Development Consultant

Johnson Controls, Inc.

peter.v.cavagnaro@jci.com

734-255-5523

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