Post on 27-Mar-2018
A REPORT TOTHE SoMo OF COMMISSIONERS OF PUBLIC UTILITIES
Electrical
Mechanical
Civil
( Protection & Control
& Distribution
System Planning
Overhaul Diesel Engines
Various Locations
July 2012
newfoundland labrador
hydroa nalcor energy company
Overhaul Diesel Engines
Newfoundland and Labrador Hydro i
SUMMARY
This report presents the capital budget proposal for diesel engine overhauls performed on a
usage-based schedule at an interval of 20,000 operating hours. Overhauls or long block
replacements are required to ensure the generator set is able to meet its Hydro expected
life of 100,000 hours. The projection of future overhauls forecasts 48 overhauls over the
2013 to 2017 period at a total estimated cost of $5.12 million.
Overhaul Diesel Engines
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 ................................................................................................ 4
3.2.1 Reliability Performance .................................................................................. 5
3.2.1.1 Outage Statistics ......................................................................................... 5
3.2.2 Safety Performance ....................................................................................... 7
3.2.3 Environmental Performance .......................................................................... 7
3.2.4 Industry Experience ....................................................................................... 8
3.2.5 Vendor Recommendations ............................................................................ 8
3.2.6 Maintenance or Support Arrangements ........................................................ 8
3.2.7 Maintenance History ..................................................................................... 8
3.2.8 Historical Information .................................................................................... 9
3.2.9 Anticipated Useful Life ................................................................................... 9
3.3 Development of Alternatives ..................................................................................... 9
3.4 Evaluation of Alternatives .......................................................................................... 9
3.4.1 Economic Analysis ........................................................................................ 10
4 CONCLUSION ..................................................................................................................... 11
4.1 Budget Estimate ....................................................................................................... 11
4.2 Project Schedule ...................................................................................................... 11
APPENDIX A ............................................................................................................................ A1
Overhaul Diesel Engines
Newfoundland and Labrador Hydro 1
1 INTRODUCTION
Hydro’s Diesel Engine Overhaul Project has been developed to ensure the reliability of
diesel engines at prime power diesel generating stations. Hydro has 21 prime power diesel
generating stations serving approximately 4,400 customers. With the exception of two
systems (Ramea and L’Anse-au-Loup), these generating stations are the sole source of
electricity for their community which means that if the station cannot meet the load then
customer outages will occur. The reliability of the prime power diesel generating stations is
single contingency, meaning that the plant is designed to be able to provide maximum load
in the event of the unavailability of up to one diesel unit (due to failure). This means that
while the failure of a single unit will not result in customer outages the failure of any
additional units before the initially failed unit is returned to service may result in customer
outages. This highlights the importance of the reliability of these diesel engines. In short,
the prime power diesel generating stations are the only power source for their community
and require major overhauls to achieve their expected service lives while providing reliable
power.
Figure 1 below is a photo of Ramea Unit 2077 prior to its installation in the Ramea Diesel
Plant.
Figure 1: Ramea Unit 2077
Overhaul Diesel Engines
Newfoundland and Labrador Hydro 2
2 PROJECT DESCRIPTION
This project is required to overhaul the diesel engines at diesel generating stations. The
project consists of overhauling 48 engines over the next five years (2013 to 2017). 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 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. For a typical unit, 20,000
operating hours accumulates on average in 8.7 years but it 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. While the specific engines projected to be due for overhaul in a
given year can vary from year to year, the number of engines projected to be due for
overhaul in a given year tends to be relatively consistent.
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 identified through 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, and fuel lines. Both rebuilds and long
block replacements use remanufactured parts and include the replacement of the fuel lines.
The long block replacement program also comes with the advantage of warranty and a
manufacturer overhauled engine that can be delivered to site. Hydro is utilizing the long
block replacement approach where possible in the northern Labrador region to minimize
travel costs and engine downtime.
Overhaul Diesel Engines
Newfoundland and Labrador Hydro 3
3 JUSTIFICATION
3.1 Existing System
The existing system of isolated diesel generating stations consists of prime power diesel
engines at 21 isolated 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 30 kW to
1,825 kW. The diesel engines range in age from one year to 41 years and currently range in
operating hours from less than 500 hours to over 122,000 hours (as of the end of 2011).
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 and/or Upgrades
Year Major Work and/or Upgrade
20121 Long block replacement of Black Tickle Unit 579
20121 Overhaul of Charlottetown Unit 2061
20121 Rebuild of Hopedale Unit 2054
20121 Rebuild of Little Bay Islands Unit 2058
20121 Rebuild of Makkovik Unit 2059
20121 Rebuild of Ramea Unit 2047
20121 Rebuild of St. Brendan’s Unit 578 (alternator only)
2012 Rebuild of Cartwright Unit 2052
2012 Long block replacement of Hopedale Unit 2074
2012 Rebuild of St. Lewis Unit 2080
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 2042
2011 Rebuild of Port Hope Simpson Unit 2043
2011 Rebuild of Rigolet Unit 2081
2011 Rebuild of Rigolet Unit 2051
2011 Rebuild of Postville Unit 577
2011 Rebuild of Hopedale Unit 2053
1 Refers to planned work for the stated year.
Overhaul Diesel Engines
Newfoundland and Labrador Hydro 4
Year Major Work and/or Upgrade
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
2010 Rebuild of Cartwright Unit 2036
2009 Rebuild of St. Brendan’s Unit 2055
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 Nain Unit 576
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 Cartwright Unit 2052
2008 Rebuild of Black Tickle Unit 2066
2008 Rebuild of Paradise River Unit 324
2008 Rebuild of Postville Unit 577
2008 Long block replacement of Makkovik Unit 3033
2007 Rebuild of Francois Unit 570
2007 Rebuild of Little Bay Islands Unit 2058
2007 Rebuild of St. Brendan’s Unit 2056
2007 Long block replacement of Charlottetown Unit 2034
2007 Rebuild of Charlottetown Unit 2061
2007 Rebuild of Black Tickle Unit 287
2007 Rebuild of Nain Unit 575
3.2 Operating Experience
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
Overhaul Diesel Engines
Newfoundland and Labrador Hydro 5
automated plants the engine mix is automatically controlled by a control system to
maximize fuel efficiency, while in a manual plant this is controlled 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.
3.2.1 Reliability Performance
A consequence of not completing this project is an increase in the frequency and duration
of customer outages (i.e. higher SAIDI and SAIFI values) as a result of an increase in diesel
unit failures.
3.2.1.1 Outage Statistics
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 - is the System Average Interruption Frequency Index per year which 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
Overhaul Diesel Engines
Newfoundland and Labrador Hydro 6
average number of customers interrupted per rotating cycle.
In this case it applies to the loss of the diesel plant.
Table 2 below lists the SAIDI Loss of Supply outage statistics for the prime power diesel
generating stations for the previous five years. Table 3 below lists the SAIFI Loss of Supply
outage statistics for the same diesel generating stations for the previous five years.
Table 2: 2007 to 2011 Outage Statistics (SAIDI Loss of Supply)
System SAIDI (Loss of Supply)
2007 2008 2009 2010 2011
TRO Central
Francois (FRS) 0.550 2.583 0.481 0.833 0.249
Grey River (GYR) 0.083 0.000 0.000 0.165 0.000
Little Bay Islands (LBI) 0.167 3.333 1.084 0.083 3.561
McCallum (MCC) 0.000 0.000 1.500 0.167 0.000
Ramea (RAM) 2.183 1.518 0.167 0.283 1.221
St. Brendan's (SBN) 0.000 0.083 0.000 0.017 0.000
TRO Northern
Charlottetown (CHT) 0.682 2.233 3.667 1.545 0.133
L’Anse-au-Loup (LAL) 0.000 1.656 0.576 1.561 1.167
Mary's Harbour (MSH) 3.925 1.205 7.284 4.408 0.661
Norman Bay (NOB) 3.553 4.129 1.250 0.167 2.834
Port Hope Simpson (PHS) 6.282 0.783 0.000 1.228 0.550
St. Lewis (SLE) 0.450 0.455 0.566 0.500 1.531
William's Harbour (WHR) 1.000 1.083 0.450 0.333 12.167
TRO Labrador
Black Tickle (BKT) 0.483 18.900 2.078 11.892 2.867
Cartwright (CTW) 1.433 6.400 0.417 3.850 0.699
Hopedale (HPD) 8.241 5.100 3.302 6.913 2.406
Makkovik (MAK) 0.500 2.717 2.933 0.238 2.087
Nain (NAN) 0.533 11.265 4.651 3.767 1.407
Paradise River (PDR) 0.267 0.269 0.383 5.050 2.924
Postville (POV) 0.617 4.400 4.500 0.901 1.866
Rigolet (RIG) 0.850 1.967 4.312 3.503 0.616
Overhaul Diesel Engines
Newfoundland and Labrador Hydro 7
Table 3: 2007 to 2011 Outage Statistics (SAIFI Loss of Supply)
System SAIFI (Loss of Supply)
2007 2008 2009 2010 2011
TRO Central
Francois (FRS) 5.000 2.000 5.961 3.000 1.987
Grey River (GYR) 1.000 0.000 0.000 1.986 0.000
Little Bay Islands (LBI) 1.000 5.993 6.000 1.000 5.947
McCallum (MCC) 0.000 0.000 1.000 1.000 0.000
Ramea (RAM) 2.000 5.266 1.000 3.000 9.537
St. Brendan's (SBN) 0.000 1.000 0.000 1.000 0.000
TRO Northern
Charlottetown (CHT) 5.990 5.000 6.000 11.953 2.000
L’Anse-au-Loup (LAL) 0.000 1.000 1.394 3.99 1.996
Mary's Harbour (MSH) 15.032 9.762 12.004 8.923 5.947
Norman Bay (NOB) 17.003 17.158 6.000 1.000 18.000
Port Hope Simpson (PHS) 13.987 4.000 0.000 4.978 3.000
St. Lewis (SLE) 5.000 2.015 2.992 3.000 7.969
William's Harbour (WHR) 5.000 13.000 6.000 4.000 2.000
TRO Labrador
Black Tickle (BKT) 4.000 17.000 10.981 4.981 4.000
Cartwright (CTW) 7.000 10.000 6.000 10.994 3.991
Hopedale (HPD) 9.009 7.000 11.000 11.602 5.902
Makkovik (MAK) 1.000 7.000 4.000 1.930 9.935
Nain (NAN) 1.000 17.998 10.951 6.937 5.935
Paradise River (PDR) 3.000 5.000 4.000 7.000 5.892
Postville (POV) 2.000 17.000 8.000 2.953 9.000
Rigolet (RIG) 7.000 4.000 8.975 2.958 1.994
3.2.2 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 possible flying hazards for the
employees in the vicinity. The risk of this occurring increases if overhauls are not
completed.
3.2.3 Environmental Performance
This project is being justified from a reliability perspective but if overhauls are not
Overhaul Diesel Engines
Newfoundland and Labrador Hydro 8
completed, failures could result in oil and glycol being released into the environment.
3.2.4 Industry Experience
Manufacturers of diesel engines will provide recommended overhaul frequencies which
typically are in the 15,000 hour range. Hydro adopted this philosophy for many years but
completed a review of its maintenance tactics in 2003 and extended the overhaul period to
20,000 hours.
3.2.5 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.
3.2.6 Maintenance or Support Arrangements
Generally, a routine annual inspection is performed by internal resources. The annual
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.
3.2.7 Maintenance History
The five-year maintenance history for the prime power diesel engines is shown in the
following table:
Overhaul Diesel Engines
Newfoundland and Labrador Hydro 9
Table 4: Five-Year Maintenance History
Year
Preventive
Maintenance
($000)
Corrective
Maintenance
($000)
Total
Maintenance
($000)
2011 69.0 782.7 851.7
2010 80.7 1,309.8 1,390.5
2009 40.2 1,265.4 1,305.6
2008 29.7 871.8 901.5
2007 24.8 950.5 975.3
3.2.8 Historical Information
Prior to 2012, diesel engine overhauls were being performed as operating projects.
Between 2007 and 2011, an average of 9.8 engines (49 over five years) were overhauled
annually. In 2012, Hydro adopted International Financial Reporting Standards (IFRS). Under
the IFRS, major overhauls are capitalized. As a result, since 2012, diesel engine overhauls
have been performed under capital projects.
3.2.9 Anticipated Useful Life
The diesel engines have an estimated service life of 25 years. Actual life depends primarily
on the operating hours of the unit.
3.3 Development of Alternatives
The alternatives considered for this overhaul project were to either rebuild the engine with
internal resources or purchase a rebuilt long block from the manufacturer. Overhauls in
areas in Central and Northern are planned to be rebuilt by internal forces, while selected
overhauls for Labrador are planned to use rebuilt long blocks from the manufacturer due to
minimizing downtime, travel, and internal resource requirements.
3.4 Evaluation of Alternatives
In evaluating the two alternatives, it was decided for the island and on the south coast of
Labrador that overhauls should typically consist of rebuilding the engines with internal
resources. In Labrador, selected engines will use long block replacements which are
essentially engines that have been rebuilt by the manufacturer.
Overhaul Diesel Engines
Newfoundland and Labrador Hydro 10
From Hydro’s experience in using long block replacements the following has been noted:
a. A reduction in downtime of the unit. The long block replacement time is
shorter than having to complete an overhaul;
b. The travel time and travel cost is less for long block replacements. This can
be amplified when weather delays occur, which are common in northern
Labrador; and
c. On the north cost of Labrador, in particular, long blocks have helped
improved resource management, to free up resources to deal with other
priority maintenance issues.
Based upon the above, the benefits are mainly in northern areas in which you have to fly in
and out, such as on the north coast of Labrador. As a result Hydro’s budget proposal for
2013 is only considering long block replacements in the Labrador region and engine rebuilds
by internal resources in the Central and Northern regions.
3.4.1 Economic Analysis
There was no economic analysis completed for the two alternatives, as the main options for
the majority of overhauls will be rebuilds of engines with internal resources. The option to
use long block replacement will be used in locations of Labrador only to reduce downtime
on a unit and help minimize internal resource requirements for overhauls due to travel time
to areas on the coast of Labrador. While long block replacements are typically marginally
more expensive than a rebuild, travel in remote areas can be a significant factor in the
overall cost. We will evaluate whether the use of rebuilds or long block replacements of
engines in Labrador is the least cost option consistent with reliability in each community.
Overhaul Diesel Engines
Newfoundland and Labrador Hydro 11
4 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.
4.1 Budget Estimate
Table 5: Project Budget Estimate Project Cost:($ x1,000) 2013 2014 Beyond Total
Material Supply 622.0 0.0 0.0 622.0
Labour 133.1 0.0 0.0 133.1
Consultant 0.0 0.0 0.0 0.0
Contract Work 15.0 0.0 0.0 15.0
Other Direct Costs 61.0 0.0 0.0 61.0
Interest and Escalation 63.6 0.0 0.0 63.6
Contingency 83.1 0.0 0.0 83.1
TOTAL 977.8 0.0 0.0 977.8
4.2 Project Schedule
Table 6: Project Schedule
Activity Start Date End Date
Planning Schedule annual overhauls January 2013 February 2013
Procurement Purchase overhaul components February 2013 March 2013
Installation Complete overhaul March 2013 December 2013
Commissioning Testing after overhaul March 2013 December 2013
Closeout Release For service and Asset Assignment September 2013 December 2013
Overhaul Diesel Engines
Appendix A
Newfoundland and Labrador Hydro A1
APPENDIX A
Diesel Engine Overhaul Five Year Plan
Overhaul Diesel Engines
Appendix A
Newfoundland and Labrador Hydro A2
Unit Planned Year of
Overhaul
2013
FRS 570 2013
GYR 2067 2013
Mobile 2071 2013
CHT 2034 2013
MSH 2037 2013
NOB 581 2013
PHS 2073 2013
WHR 580 2013
NAN 576 2013
POV 2084 2013
POV 573 2013
2014
CHT 2087 2014
MSH 2038 2014
BKT 582 2014
CTW 2052 2014
CTW 2086 2014
MAK 2059 2014
NAN 2085 2014
PDR 324 2014
2015
LBI 586 2015
MCC 2064 2015
SBN 2055 2015
MSH 2083 2015
PHS 2043 2015
HPD 2054 2015
MAK 3033 2015
NAN 574 2015
POV 577 2015
2016
FRS 587 2016
GYR 2062 2016
LBI 2035 2016
RAM 2045 2016
CHT 2079 2016
WHR 2075 2016
BKT 2066 2016
HPD 2074 2016
MAK 2029 2016
RIG 2081 2016
2017
LBI 2023 2017