overhaul diesel engines - newfoundland and … diesel engines newfoundland and labrador hydro page 1...

A REPORT TO

THE BOARD OF COMMISSIONERS OF PUBLIC UTILITIES

Electrical

Mechanical

Civil

Protection & Control

S1GNATLJL

2oü4 "DAT

Transmission & Distribution

Telecontrol-

System Planning

OVERHAUL DIESEL ENGINES

July 2011

rewfoundIand labrador

() hydroa nakor energy company

Overhaul Diesel Engines

Newfoundland and Labrador Hydro i

Table of Contents

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

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

3 EXISTING SYSTEM ............................................................................................................. 3

3.1 Age of Equipment or System ............................................................................... 3

3.2 Major Work and/or Upgrades ............................................................................. 3

3.3 Anticipated Useful life .......................................................................................... 5

3.4 Maintenance History ........................................................................................... 5

3.5 Outage Statistics .................................................................................................. 6

3.6 Industry Experience ............................................................................................. 9

3.7 Maintenance or Support Arrangements .............................................................. 9

3.8 Vendor Recommendations .................................................................................. 9

3.9 Availability of Replacement Parts ........................................................................ 9

3.10 Safety Performance ........................................................................................... 10

3.11 Environmental Performance .............................................................................. 10

3.12 Operating Regime .............................................................................................. 10

4 JUSTIFICATION ............................................................................................................... 11

4.1 Net Present Value .............................................................................................. 11

4.2 Levelized Cost of Energy .................................................................................... 11

4.3 Cost Benefit Analysis .......................................................................................... 11

4.4 Legislative or Regulatory Requirements ............................................................ 11

4.5 Historical Information ........................................................................................ 12

4.6 Forecast Customer Growth ................................................................................ 12

4.7 Energy Efficiency Benefits .................................................................................. 12

4.8 Losses during Construction ................................................................................ 12

4.9 Status Quo .......................................................................................................... 13

4.10 Alternatives ........................................................................................................ 13

5 CONCLUSION .................................................................................................................. 14

5.1 Budget Estimate ................................................................................................. 14

5.2 Project Schedule ................................................................................................ 14

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


Newfoundland and Labrador Hydro Page 1

1 INTRODUCTION

Newfoundland and Labrador Hydro’s (Hydro) Diesel Engine Overhaul Project has been

developed to ensure the reliability of diesel engines at isolated diesel generating stations.

Hydro has a total of 69 prime power diesel engines (including mobile units) at 21 isolated diesel

generating stations serving approximately 4000 customers. With the exception of one system

(Ramea), these generating stations are the sole source of electricity for their communities. The

failure of a unit at any of these stations could result in a load reduction and/or customer outage

in that community. This highlights the importance of the reliability of these diesel engines.

The prime power diesel engines are the primary power source for these communities and

require major overhauls to achieve their expected service lives.

Figure 1 below is a photo of Ramea Unit 2077 prior to its installation in the Ramea Diesel Plant.

Figure 1 – Ramea Unit 2077



2 PROJECT DESCRIPTION

This project is required to overhaul the diesel engines at diesel generating stations. The project

consists of overhauling 53 engines over the next five years (2012 to 2016). The overhaul

schedule, which can be found in Appendix A, is based on the engines being overhauled every

20,000 hours of operation. This is the criteria currently being used for diesel engine overhauls.

The overhaul schedule is a projection based on the estimate of when each engine will reach

20,000 operating hours since its last overhaul. 20,000 operating hours accumulates on average

in 7.5 years but depends on the usage of the engine. As such, this schedule is subject to change

and the year for which an engine is projected to become due for an overhaul can vary

depending on plant conditions and the actual hours accumulated.

An overhaul consists of either a rebuild or a long block replacement. A rebuild consists of the

replacement of pistons, liners, main bearings, connecting rod bearings, fuel injectors, oil cooler,

turbo charger, water pump, oil pump, cylinder heads and all necessary gaskets. Also included in

a rebuild is a bench overhaul of the fuel pump and an overhaul of the alternator typically at

40,000 hours or when the maintenance staff identifies this through their maintenance checks.

A long block replacement consists of replacement of the block of the engine minus the auxiliary

parts such as cooler, actuator, turbo chargers, manifolds, fuel lines etc. The main difference in

the long block involves the replacement of the crank shaft and the block.

The long block replacement program is relatively new to Hydro and comes with the advantage

of warranty and a manufacturer overhauled engine that can be delivered to site. Hydro is in the

process of evaluating the effectiveness of this approach and has targeted specific engines in the

Labrador Region to have long block replacement.



3 EXISTING SYSTEM

The existing system of isolated diesel generating stations consists of a total of 69 prime power

diesel engines at 21 diesel generating stations. The number of units at a generating station

ranges from three to five and the rated output of the units range from 30kW to 1375kW.

3.1 Age of Equipment or System

The diesel engines range in age from less than one year to 31 years and currently range in

operating hours from less than 1,000 hours to over 119,000 hours (as of the end of 2010).

3.2 Major Work and/or Upgrades

Please refer to Table 1 below for details concerning the major work and upgrades to each diesel

engine during the previous five years.

Table 1: Major Work or Upgrades

Year Major Work/Upgrade

2011* Rebuild of Grey River Unit# 2062

2011* Rebuild of McCallum Unit# 2063

2011* Rebuild of Ramea Unit# 2077

2011* Rebuild of St. Brendan’s Unit# 2056

2011* Rebuild of St. Lewis Unit# 2039

2011* Rebuild of William’s Harbour Unit# 2057

2011* Rebuild of Port Hope Simpson Unit# 2043

2011* Rebuild of Natuashish Unit# 2069

2011* Rebuild of Cartwright Unit# 2052

2011* Rebuild of Rigolet Unit# 2081

2011* Rebuild of Rigolet Unit# 2051

2011* Rebuild of Postville Unit# 577

2011* Rebuild of Hopedale Unit# 2053

2010 Rebuild of St. Brendan’s Unit# 578

2010 Rebuild of Ramea Unit# 2045




2010 Rebuild of Spare Unit# 2072

2010 Rebuild of Charlottetown Unit# 2079

2010 Rebuild of Mary’s Harbour Unit# 2038

2010 Rebuild of Cartwright Unit# 2045

2010 Rebuild of Nain Unit# 574



2009 Rebuild of Port Hope Simpson Unit# 2073

2009 Rebuild of Paradise River Unit# 254

2009 Rebuild of Rigolet Unit# 2065

2009 Long block replacement of Postville Unit# 573

2009 Rebuild of Makkovik Unit# 2059

2009 Long block replacement of Makkovik Unit# 2029

2009 Rebuild of Hopedale Unit# 2054

2009 Rebuild of Hopedale Unit# 2074


2009 Rebuild of Natuashish Unit# 2068



2009 Replacement of Cartwright Unit# 567 with Unit# 2086

2008 Rebuild of Grey River Unit# 2067

2008 Rebuild of Ramea Unit# 2045

2008 Long block replacement of Mary’s Harbour Unit# 2037

2008 Rebuild of Norman Bay Unit# 561

2008 Installation of Norman Bay Unit# 562

2008 Long block replacement of Port Hope Simpson Unit# 2042


2008 Rebuild of Black Tickle Unit# 2066

2008 Rebuild of Paradise River Unit# 324

2008 Rebuild of Postville Unit# 577


2007 Rebuild of Francois Unit# 570

2007 Rebuild of Little Bay Islands Unit# 2058





2007 Long block replacement of Charlottetown Unit# 2034

2007 Rebuild of Charlottetown Unit# 2061

2007 Rebuild of Black Tickle Unit# 287



2006 Rebuild of Norman Bay Unit# 563

2006 Rebuild of Port Hope Simpson Unit# 2043

2006 Rebuild of St. Lewis Unit# 2015

2006 Long block replacement of Cartwright Unit# 2036

2006 Rebuild of Postville Unit# 573

2006 Replacement of Rigolet Unit# 2049 with Davis Inlet Unit# 2027


2006 Long block replacement of Hopedale Unit# 2053



2006 Long block replacement of Mary’s Harbour Unit# 2038

* = planned

3.3 Anticipated Useful life

The diesel engines have an estimated service life of 30 years. Actual life depends primarily on

the operating hours of the unit.

3.4 Maintenance History

The five-year maintenance history for the diesel engines is shown in Table 2 below.



Table 2: Five-Year Maintenance History

Year

Preventive

Maintenance

($000)

Corrective

Maintenance

($000)

Total

Maintenance

($ 000)

2006 23.0 1,281.0 1,304.0

2007 24.2 983.6 1,007.8

2008 27.4 872.4 899.8

2009 39.9 1,371.8 1,411.7

2010 77.5 1,290.0 1,367.5

3.5 Outage Statistics

Newfoundland and Labrador Hydro tracks all distribution system outages using industry

standard indexes, SAIDI and SAIFI which are explained as follows:

SAIDI- indicates the System Average Interruption Duration Index for customers served per

year, or the average length of time a customer is without power in the respective

distribution system per year.

SAIFI - (System Average Interruption Frequency Index) indicates the average of sustained

interruptions per customer served per year or the average number of power outages a

customer has experienced in the respective distribution system per year.

Loss of Supply is defined by the CEA as:

Customer interruptions due to problems in the bulk electricity supply system such as

underfrequency load shedding, transmission system transients, or system frequency excursions.

During a rotating load shedding cycle, the duration is the total outage time until normal

operating conditions resume, while the number of customers affected is the average number of

customers interrupted per rotating cycle. In this case it applies to the loss of the diesel plant.



Table 3 below lists the SAIDI Loss of Supply outage statistics for the diesel generating stations

for the previous five years. Table 4 below lists the SAIFI Loss of Supply outage statistics for the

diesel generating stations for the previous five years.

Table 3 – 2005 to 2009 Outage Statistics (SAIDI Loss of Supply)

SAIDI (Loss of Supply)

System 2005 2006 2007 2008 2009

TRO Central

Francois (FRS) 0.900 0.117 0.550 2.583 0.481

Grey River (GYR) 0.167 0.086 0.083 0.000 0.000

Little Bay Islands (LBI) 1.217 1.633 0.167 3.333 1.084

McCallum (MCC) 1.000 0.083 0.000 0.000 1.500

Ramea (RAM) 0.415 2.158 2.183 1.518 0.167

St. Brendan's (SBN) 0.683 0.083 0.000 0.083 0.000

TRO Northern

Charlottetown (CHT) 2.102 3.350 0.682 2.233 3.667

L'Anse au Loup 2.573 0.867 0.000 1.655 0.576

Mary's Harbour (MSH) 1.915 3.883 3.925 1.205 7.284

Norman Bay (NOB) 3.017 1.450 3.553 4.129 1.250

Port Hope Simpson (PHS) 2.516 6.000 6.282 0.783 0.000

St. Lewis (SLE) 1.500 1.634 0.450 0.455 0.566

William's Harbour (WHR) 0.333 1.404 1.000 1.083 0.450

TRO Labrador

Black Tickle (BKT) 1.599 2.233 0.483 18.900 2.078

Cartwright (CTW) 1.179 1.233 1.433 6.400 0.417

Hopedale (HPD) 5.005 2.391 8.241 5.100 3.302

Makkovik (MAK) 0.967 3.745 0.500 2.717 2.933

Nain (NAN) 3.657 6.778 0.533 11.265 4.651

Paradise River (PDR) 0.717 0.383 0.267 0.269 0.383

Postville (POV) 1.250 13.068 0.617 4.400 4.500

Rigolet (RIG) 1.861 3.683 0.850 1.967 4.312



Table 4 – 2005 to 2009 Outage Statistics (SAIFI Loss of Supply)

SAIFI (Loss of Supply)

System 2005 2006 2007 2008 2009

TRO Central

Francois (FRS) 4.000 1.000 5.000 2.000 5.961

Grey River (GYR) 1.000 1.029 1.000 0.000 0.000

Little Bay Islands (LBI) 8.000 11.000 1.000 5.993 6.000

McCallum (MCC) 2.000 1.000 0.000 0.000 1.000

Ramea (RAM) 4.362 6.283 2.000 5.266 1.000

St. Brendan's (SBN) 3.000 1.000 0.000 1.000 0.000

TRO Northern

Charlottetown (CHT) 9.010 10.000 5.990 5.000 6.000

L'Anse au Loup 5.999 3.001 0.000 0.999 1.394

Mary's Harbour (MSH) 17.008 9.996 15.032 9.762 12.004

Norman Bay (NOB) 12.000 6.000 17.003 17.158 6.000

Port Hope Simpson (PHS) 12.000 8.000 13.987 4.000 0.000

St. Lewis (SLE) 8.000 8.000 5.000 2.015 2.992

William's Harbour (WHR) 1.000 11.026 5.000 13.000 6.000

TRO Labrador

Black Tickle (BKT) 7.990 8.000 4.000 17.000 10.981

Cartwright (CTW) 4.988 5.003 7.000 10.000 6.000

Hopedale (HPD) 5.918 2.992 9.009 7.000 11.000

Makkovik (MAK) 6.000 5.978 1.000 7.000 4.000

Nain (NAN) 7.018 10.002 1.000 17.998 10.951

Paradise River (PDR) 8.000 6.000 3.000 5.000 4.000

Postville (POV) 6.000 11.000 2.000 17.000 8.000

Rigolet (RIG) 3.947 10.000 7.000 4.000 8.975



3.6 Industry Experience

Manufacturers of diesel engines will provide recommended overhaul frequencies which

typically are in the 15,000 hour range. Hydro completed a review of its maintenance tactics in

2003 and extended the overhaul period to 20,000 hours.

3.7 Maintenance or Support Arrangements

For the most part, routine maintenance is performed by internal resources. Routine

maintenance consists of an annual inspection. The inspection checks the fuel, coolant, and

exhaust systems as well as the engine structure. Problems identified during the inspection are

typically corrected during the inspection. If an engine fails prematurely, the manufacturer is

typically consulted to help with a failure analysis.

Also to help manage the service of the parts for diesel engine, blanket orders have been set up

for Caterpillar and Detroit Diesel engines. Such arrangements are necessary to ensure lead

times on parts are acceptable and Hydro does not have to incur the cost of stocking diesel parts

in inventory.

3.8 Vendor Recommendations

The diesel engine manufacturers generally recommend an overhaul interval of 15,000 hours but

as a result of a review of maintenance tactics and failure history it was decided to extend

Hydro’s overhauls to 20,000 hours.

3.9 Availability of Replacement Parts

Hydro history has shown that parts are readily available for Toromont and Detroit Diesel

engines, while the Mitsubishi engine parts have larger lead times and can present operational



problems at times.

3.10 Safety Performance

This is a reliability-based project. However, if this project is not executed, there is a higher risk

of diesel engine failure and diesel engine failure can result in extended customer outages which

can negatively impact public safety.

As well diesel engines can fail catastrophically with pieces of the engine becoming projectiles

presenting possible flying object hazards for the employees in the vicinity. The risk of this

occurring increases if overhauls are not completed.

3.11 Environmental Performance

This project is being justified from a reliability perspective but if overhauls are not completed,

failures could result in oil and glycol being released into the environment.

3.12 Operating Regime

Isolated diesel generation operates continuously since it provides the primary source of

electricity to communities isolated from the province’s electrical grid. A given unit is not in

service continually since the number of units in service varies based on the demand. In

automated plants the engine mix is automatically controlled by a control system to maximize

fuel efficiency, while in a manual plant this control is completed by the operator.

In any of the plants the operator has the flexibility to shut down engines for maintenance

provided there is another engine available to take the load for that time. As a result outages to

engines can occur without outages to customers.



4 JUSTIFICATION

Hydro’s current maintenance philosophy is to complete an engine overhaul on all diesel engines

every 20,000 hrs. This philosophy was established as a result of a review of the maintenance

tactics and failure history in 2003. Performing overhauls too frequently results in additional

expenditure for negligible improvement in reliability. An overhaul interval of 20,000 hours is

considered to be the optimum interval for providing least-cost, reliable electrical service.

4.1 Net Present Value

A net present value calculation was not performed for this project as the justification is

reliability-based and there is no option but to overhaul the engines.

4.2 Levelized Cost of Energy

The capital expenditures for this project will not affect the levelized cost of energy for the

system.

4.3 Cost Benefit Analysis

A cost benefit analysis is not required for this project proposal, as the project is required for

reliability reasons and there is no option but to overhaul the engines.

4.4 Legislative or Regulatory Requirements

This project does not involve any legislative or regulatory requirements.



4.5 Historical Information

Currently, diesel engine overhauls are being performed at 20,000 hour intervals under

operating projects. Between 2006 and 2010, an average of 10.8 engines (54 over 5 years) have

been overhauled annually. Up to the present, these overhauls have been done as operating

projects. However, in 2012, Nalcor Energy is adopting International Financial Reporting

Standards (IFRS). Under the IFRS, major overhauls are capitalized. As a result, beginning in

2012, diesel engine overhauls are required to be performed under capital projects.

4.6 Forecast Customer Growth

This project is not required due to forecasted customer growth but required to maintain

reliability.

4.7 Energy Efficiency Benefits

There are no energy efficiency benefits (or losses) associated with this project.

4.8 Losses during Construction

The overhaul of each diesel unit will be performed during a scheduled outage. These outages

are designed around the system load requirements and do not require any customer outages.

Therefore, there are no production or revenue losses resulting from this project.



4.9 Status Quo

The consequence of not completing this project is an increase in the frequency and duration of

customer outages as a result of an increase in diesel unit failures. Unlike with the province’s

interconnected system (in which the loss of a generating unit can be compensated for with

another generating unit elsewhere on the system), an isolated diesel plant has no other

generation on which to rely which means there is a higher probability that the loss of a diesel

unit will result in a load reduction and/or customer outage.

4.10 Alternatives

There are no alternatives to overhauling the engine as it is a requirement to attain the service

life of the unit. However for overhauls Hydro is using two approaches, rebuild the engine with

internal resources or purchase a rebuilt long block from the manufacturer as is stated earlier in

this report.



5 CONCLUSION

This project is necessary in order to provide least-cost, reliable electrical service to the

customers served by isolated diesel generation. Overhauling diesel engines is a necessity in

operating this type of equipment.

5.1 Budget Estimate

Table 5 – Budget Estimate

Project Cost:($ x1,000) 2012 2013 Beyond Total

Material Supply 585.4 585.4 1,756.2 2,927.0

Labour 132.0 132.0 396.0 660.0

Consultant 0.0 0.0 0.0 0.0

Contract Work 16.6 16.6 49.8 83.0

Other Direct Costs 73.4 73.3 219.8 366.3

Interest and Escalation 88.8 109.4 474.7 672.9

Contingency 77.9 77.9 233.7 389.5

TOTAL 974.1 994.6 3,130.2 5,098.7

5.2 Project Schedule

Table 6 – Annual Project Schedule

Activity Milestone

Initial Planning and Equipment Ordering Tendering February – July

Equipment Delivery March – August

Equipment Installations and Commissioning March – October

Project In Service March – October

Project Completion and Close Out December


Appendix A

Newfoundland and Labrador Hydro A1

APPENDIX A


Appendix A


Overhaul Schedule Unit Projected Year of

Overhaul

LBI 2058 2012

RAM 2047 2012

CHT 2079 2012

PHS 2042 2012

PHS 2073 2012

SLE 2080 2012

BKT 579 2012

HPD 2054 2012

MAK 2059 2012

NAT 2076 2012

POV 573 2012

FRS 570 2013

GYR 2067 2013

CHT 2034 2013

WHR 2075 2013

HPD 2074 2013

NAN 576 2013

NAN 2085 2013

NAT 2068 2013

PDR 324 2013

POV 2084 2013

MCC 2064 2014

SBN 2055 2014

CHT 2061 2014

MSH 2038 2014

BKT 582 2014

CTW 2052 2014

MAK 2029 2014

NAN 574 2014

NAT 2070 2014

POV 577 2014


Appendix A


Overhaul Schedule Unit Projected Year of

Overhaul

RIG 2081 2014

FRS 566 2015

GYR 2062 2015

NOB 581 2015

Mobile 2044 2015

CTW 2036 2015

CTW 2086 2015

HPD 2054 2015

HPD 2053 2015

HPD 2074 2015

PDR 585 2015

POV 2084 2015

RAM 2045 2016

SBN 2056 2016

MSH 2037 2016

WHR 580 2016

BKT 579 2016

MAK 3033 2016

NAN 576 2016

NAN 2085 2016

NAT 2069 2016

RIG 2065 2016

overhaul diesel engines - newfoundland and … diesel engines newfoundland and labrador hydro page 1...

Documents