automate generator deluge systems units 5 and 6 – bay d'espoir

A REPORT TO

THE BOARD OF COMMISSIONERS OF PUBLIC UTILITIES

Electrical

Mechanical

Civil

Protection & Control

& Distribution:::System Planning

Automate Generator Deluge Systems on Units

5 and 6

Bay d'Espoir Hydroelectric Generating Station

March 2012

newfoundland labrador

hydroa nalcor energy company

Automate Generator Deluge system on Units 5 and 6 in Bay d’Espoir

Newfoundland and Labrador Hydro i

SUMMARY

This project is the first year of a three year program to replace the existing generator deluge

systems on the seven hydroelectric generating units in Powerhouse 1 and 2 at Bay d’Espoir

Hydroelectric Generating Station (Bay d’Espoir). Under this project two units will be

upgraded. A deluge system is a fire suppression method that will spray water onto the

generator in the event of a fire. At present these systems have to be activated manually by

plant personnel opening a deluge valve that is located next to the generator. This procedure

has been identified by Hydro’s insurance provider, FM Global, as a significant risk and they

have recommended automating these systems to improve response time and ensure a

response is made if human access is not possible. An automatic system will also provide a

safer fire protection system for plant personnel to operate. In addition the National Fire

Protection Association recommends providing automated systems for generator fire

protection.


Newfoundland and Labrador Hydro ii

TABLE OF CONTENTS

SUMMARY .................................................................................................................................. i

1 INTRODUCTION ................................................................................................................... 1

2 PROJECT DESCRIPTION ........................................................................................................ 2

3 JUSTIFICATION .................................................................................................................... 3

3.1 Existing System .......................................................................................................... 3

3.2 Operating Experience ................................................................................................ 6

3.2.1 Legislative or Regulatory Requirements ........................................................ 6

3.2.2 Safety Performance ....................................................................................... 6

3.2.3 Industry Experience ....................................................................................... 7

3.2.4 Maintenance or Support Arrangements ........................................................ 7

3.2.5 Maintenance History ..................................................................................... 7

3.2.6 Anticipated Useful Life ................................................................................... 8

3.3 Development of Alternatives ..................................................................................... 8

4 CONCLUSION ....................................................................................................................... 9

4.1 Budget Estimate ......................................................................................................... 9

4.2 Project Schedule ...................................................................................................... 10

APPENDIX A ............................................................................................................................. A1

APPENDIX B ............................................................................................................................. B1

APPENDIX C ............................................................................................................................. C1


Newfoundland and Labrador Hydro 1

1 INTRODUCTION

Hydro’s largest hydroelectric generating station in the Island Interconnected System is

located at Bay d’Espoir. The Bay d’Espoir Hydroelectric Generating Station consists of seven

generating units producing a total capacity of 604 MW which is approximately 39 percent of

the Island Interconnected System’s installed capacity. The company’s insurer, FM Global,

visits hydro generating stations annually and makes recommendations for improvements

that will reduce the risk of asset damage, increased costs, and power interruption. This

report addresses a condition identified by FM Global. At present the fire protection systems

serving the generating units at Bay d’Espoir are all manually activated. This project will

replace these systems on two generating units with automatically activated systems as

recommended by FM Global and the National Fire Protection Association (NFPA).



2 PROJECT DESCRIPTION

The scope of work for this project is to replace the existing manually operated generator

deluge system on generating Units 5 and 6 with a modern fully automatic deluge system. A

new deluge control cabinet will be installed along with a new sprinkler distribution ring as

the existing ring is not compatible with the new system as well it is not advisable to connect

a new automated control to the old existing sprinkler ring. The existing piping is over 45

years old and its condition is unknown. In the event of a fire the reliability of the existing

piping with a new automated control would be uncertain. The distribution ring is a system

of pipes that surround the generator and deliver water to spray nozzles in the event of a

fire. When the system is activated water flows immediately through all nozzles at once. The

budget estimate to complete this project is $532,000 and the work is scheduled to be

performed in 2013. An outage on each generating unit will be required to complete the new

installations. The outages will take place concurrently during the annual maintenance

period and will be two to four weeks in duration.



3 JUSTIFICATION

This project is justified on the need for Hydro to upgrade the existing equipment to reduce

exposure to harm by operations personnel and reduce the potential for damage to

equipment in the event of a fire on a generator.

The FM Global Risk Report for Bay d’Espoir (see Appendix A, Section 07-11-002) indicates

the hazard associated with a manual system is the ability of a generator fire to spread

rapidly during the time it takes an operator to respond to the initial alarm. The longer it

takes to respond to a fire would result in more extensive damage to the equipment and

increased cost of repairs. A large fire could also prevent access to the manual valves

altogether leading to greater damage with potential loss of 450 MW of generating capacity

to the Island Interconnected System for a period of time ranging in duration from several

months to over a year.

Hydro has not experienced a fire on any of its seven generating units at Bay d’Espoir

however the existing manual system poses a significant risk if there is a fire. It is required

that the deluge systems for each generating unit be upgraded to a fully automatic system to

limit employee exposure to harm and reduce potential equipment damage in the event of a

fire.

3.1 Existing System

Each generator at the Bay d’Espoir Hydroelectric Generating Station is equipped with a

manually operated deluge system that can be used to extinguish a fire that may occur in the

vicinity of the upper and lower stator windings. There have been no major upgrades of the

deluge system since the original installation.

The existing generator fire protection systems consist of an upper and lower sprinkler ring

connected to the main firewater header through a series of piping and valves. In the event



of a fire, an alarm sounds in the control room. An operations person is then fitted with a

self-contained breathing apparatus (SCBA) and proceeds to the appropriate generating unit

to determine if a fire exists. If a fire is present and the unit is still rotating the operator must

stop the unit, open the main disconnect and place the main ground switch to the “On”

position to ensure the unit is de-energized. Once the unit has stopped rotating and has

been de-energized the operator proceeds to the proper generator manual deluge station

and opens the main fire water valve to release water onto the fire (See Figure 1).

FM global indicates that a generator fire could occur if there is a short circuit which could

ignite the insulation on the generator. The fire would start small, however once established

fire can spread rapidly within two to three minutes. The estimated response time of

operations, from the time they receive the alarm to when the unit deluge system is

activated, is approximately six to eight minutes. By this time there could be significant

damage done to the generator and access to the manual deluge valve maybe impeded. The

approximate distance from the valve to the generating unit is 16 feet (Figure 2).

The proposed new system will be activated automatically such that when a fire is detected,

by a sensor located in the generator area, the generating unit will be shut down and de-

energized, the ventilation fans shut down and exhaust louvers closed, and then water

applied to the fire. Shutting down the ventilation system helps to control the fire by

reducing the supply of oxygen to a fire. The operators remain safe in the control room

during automatic activation.

FM Global updated their risk report for Powerhouse 1 and 2 in Bay d’Espoir in 2011 and

identified the lack of an automatic deluge system on generating Units one, three, four and

seven as a hazard that needs to be corrected. This recommendation was based on the units

that still had asphalt windings (Units 1, 3 and 4) or a unit in a different powerhouse (Unit 7).

As noted in the FM report Hydro indicated that all the generating units from one to seven

will be converted to automatic systems. Hydro is taking this approach as this would correct

the operations safety hazard and give better protection to all the units, and would also



comply with National Fire Protection Association (NFPA).

Figure 1: Typical Deluge Valve Arrangement on Units 1 – 6

Figure 2: Deluge Valve (left) with respect to Generating Unit (right)



3.2 Operating Experience

FM Global believes that in the time taken for an operator to respond to a fire alarm on a

generating unit a potentially small fire could turn into something much larger thus leading

to more equipment damage and increased replacement costs. An automatic system is more

effective because there is no delay in responding to an alarm thereby ensuring a greater

potential for extinguishing a fire before major equipment damage occurs.

3.2.1 Legislative or Regulatory Requirements

The National Fire Protection Association (NFPA) maintains a recommended practice

referred to as “NFPA851: Recommended Practice for Fire Protection for Hydroelectric

Generating Plants”. Within this document the NFPA recommends that the protection of

generator windings be provided by an automatically actuated fire suppression system.

Currently Hydro meets this recommended practice at all of its hydroelectric generating

stations with the exceptions of Powerhouse 1 and 2 at Bay d’Espoir. The applicable section

of NFPA 851 is provided in Appendix B.

3.2.2 Safety Performance

In the event of a fire a plant operator must be equipped with SCBA before entering the

generator hall. The operator comes in close proximity to a generating unit that may be on

fire to access manual control valves. The operator first verifies that there is a fire before

proceeding to follow a series of steps to ensure the unit is stopped and de-energized before

the deluge valve is manually opened to release water. This current practice exposes the

operator to unnecessary risk and increases the likelihood of personal harm and extensive

equipment damage.



3.2.3 Industry Experience

The Centre for Energy Advancement through Technological Innovation (CEATI), an

international utilities interest group in which Hydro participates, released a technology

review in 2006 titled “Fire Protection and Suppression in Hydroelectric Plants” that outlines

the current design standard currently used by BC Hydro (see Appendix C). For generator

housings BC Hydro ensures that each generator shall incorporate an automatic water spray

type fire protection system, similar to what Hydro is proposing for Bay d’Espoir. Hydro also

meets this standard at all of its other hydraulic generating.

3.2.4 Maintenance or Support Arrangements

Maintenance of the current generator deluge systems in Bay d’Espoir has been completed

by Hydro.

3.2.5 Maintenance History

There is no maintenance history specifically for the generator deluge system. The five year

history for the Fire Protection and Detection System is provided in Table 1.

Table 1: Five-Year Maintenance History

– Fire Protection and Detection System

Year

Preventive

Maintenance

($000)

Corrective

Maintenance

($000)

Total

Maintenance

($000)

2011 1.4 0.9 2.3

2010 0.4 9.1 9.5

2009 0.0 6.0 6.0

2008 0.6 3.9 4.5

2007 4.8 1.3 6.1



3.2.6 Anticipated Useful Life

The anticipated useful life for fire fighting equipment is 45 years.

3.3 Development of Alternatives

The status quo is not acceptable and there are no viable alternatives to this project. When

obtaining budgetary quotes for this project only the full system was considered for

replacement. This was under the recommendation of a certified sprinkler contractor as the

proposed system is different than the existing and is assumed to not be compatible, and

even if the sprinkler ring is compatible it is not advisable to leave the 40 plus year old piping

in place while upgrading to a fully automated system.



4 CONCLUSION

The current manual generator deluge systems on Units 5 and 6 in Bay d’Espoir need to be

upgraded to fully automatic control. A fully automated system will reduce the safety risk to

plant operators and also will have the potential to significantly reduce equipment damage

in the event of a fire. An automated deluge system will align Hydro with FM Global

recommendations, other Hydro generation plant installations, the standard put forth by the

NFPA Recommended Practice, as well as the industry standard currently adopted by CEATI.

All other Hydro Generating Plants have an automatic generator deluge system. The status

quo is not acceptable and there is no viable alternative to this project.

4.1 Budget Estimate

A budget estimate for this project is provided in Table 2.

Table 2: Project Budget Estimate Project Cost:($ x1,000) 2013 2014 Beyond Total

Material Supply 40.0 0.0 0.0 40.0

Labour 160.6 0.0 0.0 160.6

Consultant 24.9 0.0 0.0 24.9

Contract Work 170.0 0.0 0.0 170.0

Other Direct Costs 16.1 0.0 0.0 16.1

Interest and Escalation 38.1 0.0 0.0 38.1

Contingency 82.3 0.0 0.0 82.3

TOTAL 532.0 0.0 0.0 532.0



4.2 Project Schedule

The anticipated schedule for this project is provided in Table 3.

Table 3: Project Schedule

Activity Start Date End Date

Planning Review Scope

Confirm Schedule

Review Budget

February 2013 February 2013

Design Submit design transmittal

Risk workshop

March 2013 March 2013

Procurement Confirm Schedule

Tender materials / review tenders

Award tender for supply

March 2013 March 2013

Construction Safety meetings

Schedule meetings

Risk / Change management

Site safety tour

May 2013 May 2013

Commissioning Safety meeting

training

June 2013 June 2013

Closeout Financial close out

Post implementation review

October 2013 October 2013


Appendix A

Newfoundland and Labrador Hydro A1

APPENDIX A

FM Global Risk Report


Appendix A



Appendix B

Newfoundland and Labrador Hydro B1

APPENDIX B

NFPA 851


Appendix B

Newfoundland and Labrador Hydro B2


Appendix C

Newfoundland and Labrador Hydro C1

APPENDIX C

BC Hydro Standard


Appendix C


automate generator deluge systems units 5 and 6 – bay d'espoir

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