EMD Diesel Generator Specifications: The Complete 645 and 710 Model and Rating Guide
If you have inherited an EMD powered station, been offered a used EMD set, or are costing an overhaul on an ageing fleet, the first thing you need is a straight answer on what the machine is actually rated to do. EMD Diesel Generator Specifications are not always easy to pin down, because the same engine block appears in locomotive, marine, drilling, and stationary service at materially different ratings, and because the sets in circulation today were catalogued across four decades of superseded literature. Getting the rating wrong at feasibility stage is expensive. Getting it wrong at commissioning stage is dangerous.
This guide sets out the published continuous ratings for EMD stationary generator sets built on the 645 and 710 engine families, explains how the model designations decode, and shows what to verify before money changes hands. USP&E Global has spent 25 years designing, building, and operating power stations in markets where a mis specified prime mover means a mine stops or a hospital goes dark. We have delivered more than 150 projects across 35+ countries with 350+ engineers and technicians, and we hold ISO 9001:2015 and ISO 45001:2018 certification. Your project is the one that has to run. Our job is to make sure the numbers you build it on are real.
Two definitions before we start, because the rest of this guide depends on them. BHP is brake horsepower, the mechanical power measured at the engine crankshaft. Generator set kW is the electrical power delivered at the alternator terminals, which is always lower, because the alternator is not perfectly efficient.
What EMD Diesel Generator Specifications Actually Describe
EMD stands for Electro-Motive Diesel, originally the Electro-Motive Division of General Motors and now part of Progress Rail. The engines are two-stroke, medium speed, 45 degree V configuration diesels. They were designed for locomotive service and adapted to marine propulsion, offshore drilling, and stationary power generation.
There is a persistent misconception worth correcting here. EMD 645 and 710 engines are diesel engines. The EMD 710 is a line of diesel engines built by Electro-Motive Diesel, and the 710 series replaced the earlier EMD 645 series. The EMD 645 is likewise a family of two-stroke diesel engines designed and manufactured by the Electro-Motive Division of General Motors, intended primarily for locomotive, marine, and stationary engine use. Natural gas operation on these blocks exists only as a third party dual fuel retrofit using a diesel pilot for ignition, not as a factory product. Any listing describing a factory EMD natural gas generator should be treated with caution.
The engine family is identified by displacement per cylinder in cubic inches.
| EMD Engine Family | Displacement Per Cylinder | Bore and Stroke | Cylinder Counts | Typical Service |
| EMD 567 | 567 cu in (9.29 L) | 8.5 in x 10 in | V6 to V16 | Legacy locomotive and marine, largely retired |
| EMD 645 | 645 cu in (10.6 L) | 9.06 in x 10 in | V6, V8, V12, V16, V20 | Locomotive, marine, stationary generation |
| EMD 710 | 710 cu in (11.6 L) | 9.06 in x 11 in | V8, V12, V16, V20 | Current locomotive, marine, stationary generation |
The 645 and 710 share a bore. The 710 achieves greater output through a stroke increase, taking the 645 design from a 10 inch to an 11 inch stroke. This matters commercially, because many 710 components are not interchangeable with 645 components despite the visual similarity between the two engines.
How to Decode an EMD Model Designation
Read the designation in three parts. Take the stationary set SE16G4C as the worked example.
- SE is the application prefix. SE denotes a Stationary Equipment Set. ME denotes a Marine Equipment Set. The prefix changes the published rating even when the engine is identical.
- 16 is the cylinder count.
- G4C is the engine variant. The letter indicates the engine family generation, where E and F variants sit on the 645 block and G variants sit on the 710 block. The trailing number and letter identify the specific build standard.
The engine model is written separately in the form 16-710G4C, meaning a 16 cylinder 710 series engine to the G4C standard.
EMD Diesel Generator Specifications by Model: Stationary Set Continuous Ratings
The table below sets out published continuous ratings for EMD stationary generator sets. Electro-Motive Diesel powered stationary units provide 800 to 5,000 brake horsepower for generator set and mechanical drive applications using two-cycle roots blown or turbocharged engines, and the ratings are quoted on the basis of 96 percent generator efficiency.
| EMD Diesel Generator Specifications | Engine Model | Rated Speed (RPM) | Continuous Engine BHP | Generator Set kW | Approx. MW |
| SE8E1 (roots blown) | 8-645E1 | 750 | 800 | 570 | 0.57 |
| SE8E1 (roots blown) | 8-645E1 | 900 | 1,050 | 745 | 0.75 |
| SE12E1 (roots blown) | 12-645E1 | 750 | 1,200 | 865 | 0.87 |
| SE12E1 (roots blown) | 12-645E1 | 900 | 1,500 | 1,075 | 1.08 |
| SE16E1 (roots blown) | 16-645E1 | 750 | 1,700 | 1,210 | 1.21 |
| SE16E1 (roots blown) | 16-645E1 | 900 | 2,100 | 1,500 | 1.50 |
| SE8F4B (turbocharged) | 8-645F4B | 750 | 1,425 | 1,010 | 1.01 |
| SE8F4B (turbocharged) | 8-645F4B | 900 | Not published in source | 1,210 | 1.21 |
| SE12F4B (turbocharged) | 12-645F4B | 750 | 2,140 | 1,530 | 1.53 |
| SE12F4B (turbocharged) | 12-645F4B | 900 | 2,550 | 1,825 | 1.83 |
| SE16F4B (turbocharged) | 16-645F4B | 750 | 2,950 | 2,100 | 2.10 |
| SE16F4B (turbocharged) | 16-645F4B | 900 | 3,505 | 2,500 | 2.50 |
| SE20F4B (turbocharged) | 20-645F4B | 750 | 3,600 | 2,580 | 2.58 |
| SE20F4B (turbocharged) | 20-645F4B | 900 | 4,000 | 2,865 | 2.87 |
| SE8G4C (turbocharged) | 8-710G4C | 750 | 1,675 | 1,200 | 1.20 |
| SE8G4C (turbocharged) | 8-710G4C | 900 | 2,000 | 1,440 | 1.44 |
| SE12G4C (turbocharged) | 12-710G4C | 750 | 2,495 | 1,790 | 1.79 |
| SE12G4C (turbocharged) | 12-710G4C | 900 | 3,000 | 2,150 | 2.15 |
| SE16G4C (turbocharged) | 16-710G4C | 750 | 3,325 | 2,385 | 2.39 |
| SE16G4C (turbocharged) | 16-710G4C | 900 | 4,000 | 2,865 | 2.87 |
| SE20G4C (turbocharged) | 20-710G4C | 750 | 4,155 | 2,980 | 2.98 |
| SE20G4C (turbocharged) | 20-710G4C | 900 | 5,000 | 3,580 | 3.58 |
Source: Stewart and Stevenson EMD Powered Products catalogue, 2014, authorised Electro-Motive Diesel distributor. The 645 based E and F series ratings are drawn from legacy EMD stationary literature and should be confirmed against the nameplate on any specific unit.
Three observations that matter when you read this table.
The rated speed sets the frequency. A four pole alternator at 900 RPM produces 60 Hz. A set at 750 RPM with an eight pole alternator produces 50 Hz. This is why the same engine appears twice at two different outputs. Do not assume a unit can be moved between 50 Hz and 60 Hz markets without engineering review.
Turbocharging is worth roughly 75 percent more power from the same block. The roots blown 16-645E1 delivers 1,500 kW at 900 RPM. The turbocharged 16-645F4B on the same block delivers 2,500 kW at the same speed.
The whole EMD stationary range sits between 0.57 MW and 3.58 MW per set. That places it squarely in the distributed generation and industrial band rather than utility scale. Utility scale duty is normally reached by installing multiple sets in parallel.
Roots Blown Versus Turbocharged EMD Diesel Generator Specifications
The single biggest divide in the EMD stationary range is aspiration. Two-stroke engines cannot draw their own air on the intake stroke, so every EMD engine needs forced induction simply to run. The question is what supplies it.
| Characteristic | Roots Blown (E Series) | Turbocharged (F and G Series) |
| Air supply | Gear driven Roots type blower, mechanically coupled | Exhaust driven turbocharger with clutch driven blower at low load |
| Output per cylinder | Lower | Substantially higher |
| Parasitic load | Continuous, driven off the crankshaft | Minimal above half load |
| Fuel consumption | Higher per kWh | Lower per kWh |
| Mechanical complexity | Lower | Higher, adds turbocharger overhaul scope |
| Load response | Very fast | Fast, with a short lag from low load |
| Best application | Standby, low hour duty, simplicity priority | Base load, prime power, fuel cost sensitive sites |
The commercial read is straightforward. If the set will run a few hundred hours a year on standby, a roots blown machine is simpler and cheaper to maintain. If the set is carrying a mine, a processing plant, or an island grid for thousands of hours a year, the fuel saving from turbocharging repays the added overhaul scope many times over. Fuel is normally the dominant lifetime cost in any thermal plant, a pattern visible in the operating cost data published by the U.S. Energy Information Administration.
Marine and Drilling Ratings: Why the Same Engine Shows Different Specifications
An EMD engine does not have one rating. It has a rating per application, because duty cycle, classification society rules, and cooling assumptions differ. This is the most common source of confusion when a broker quotes a figure that does not match the nameplate.
| Application | Model Designation | Engine Model | Rated Speed (RPM) | Engine BHP | Output kW |
| Stationary generator set | SE20G4C | 20-710G4C | 900 | 5,000 | 3,580 |
| Marine ships service generator | ME20G7C | 20-710G7C | 900 | 5,000 | 3,580 |
| Marine drilling power unit | ME20G7C | 20-710G7C | 900 | 5,500 | 3,950 |
| Marine propulsion (ABS rated) | ME20G7C | 20-710G7C | 900 | 5,000 | 3,730 |
Source: Stewart and Stevenson EMD Powered Products catalogue, 2014.
Note what happens across those four rows. The same 20 cylinder 710 engine is published at 5,000 BHP in stationary and ships service duty, and at 5,500 BHP as a drilling power unit. The propulsion row shows 3,730 kW because that figure is mechanical output at the shaft, not electrical output at alternator terminals.
The practical rule: never accept a kW figure without the application, the rated speed, and the basis of the rating. A number quoted without those three qualifiers is not a specification. It is a sales claim.
Emissions, Ambient Conditions, and the Specifications Nobody Quotes
Published ratings are reference ratings. Site conditions move them, sometimes considerably.
Altitude and ambient temperature derate the engine. Every naturally aspirated or forced induction diesel loses output as air density falls. A set rated at sea level and 25 degrees Celsius will not make nameplate at 1,500 metres in a 40 degree afternoon. Derate factors must come from the engine manufacturer’s curves for the specific build, not from a rule of thumb.
Fuel specification changes everything downstream. EMD stationary sets are distillate diesel machines. Attempting to run them on heavy fuel oil without a purpose engineered fuel treatment and heating train is not a modification, it is a failure mode. Any fuel supply should be validated by third party laboratory analysis before an engine is committed to a site.
Emissions compliance is jurisdictional and it is live. Two-stroke diesels of this generation produce meaningfully higher oxides of nitrogen than modern four-stroke equivalents. In the United States, stationary compression ignition engines fall under New Source Performance Standards administered by the U.S. Environmental Protection Agency, and applicable limits depend on engine size, build date, and whether the unit is classified as emergency or non emergency. Current marine and offshore EMD 710 packages are certified to EPA Tier 3 and IMO Annex VI Tier 2 for their 60 Hz ratings, but that certification does not transfer automatically to a legacy stationary set. Confirm the applicable rule and the specific engine certification with the regulator before you commit capital.
Grid code compliance is separate again. Frequency response, reactive capability, and fault ride through obligations vary by market. In many frontier grids the interconnection requirement is the binding constraint on plant design rather than the generation technology itself, a theme documented across the International Energy Agency country programmes and the World Bank energy data portfolio.
How to Verify EMD Diesel Generator Specifications Before You Buy
An EMD set that has been properly maintained is a durable industrial asset. An EMD set that has been run hard and documented poorly is a liability wearing the same paint. These ten checks separate the two. They apply whether you are buying, valuing, or taking over an installed fleet.
- Read the nameplate, not the advertisement. Photograph the engine and alternator nameplates and the serial numbers. Match them against the model designation being quoted. Mismatches between advertised and stamped designations are common in the used market.
- Establish original hours and hours since major overhaul separately. These are two different numbers and both matter. A set with 90,000 original hours and 4,000 hours since a full rebuild is a materially different asset from one with 40,000 unrebuilt hours.
- Obtain the borescope report. A recent borescope of cylinder liners, piston crowns, and ports is the cheapest meaningful condition evidence available. If none exists, commission one before contracting.
- Request the full service and overhaul history. Look for the interval discipline, not just the last entry. Two-stroke EMD engines reward scheduled attention and punish deferral.
- Confirm what is actually in the scope of supply. Engine only, engine plus alternator, or engine plus alternator plus control panel are three different purchases. Balance of plant, meaning radiators, day tanks, switchgear, transformers, exhaust, and interconnection, is frequently excluded and frequently the larger cost.
- Verify the aspiration and the turbocharger condition. On F and G series sets the turbocharger is a major overhaul item with its own service history. Ask for it explicitly.
- Establish the last load bank test date and result. A set that has not been load tested has not been proven. Sustained load testing at rated output, not a brief no load run, is the standard.
- Confirm the prior application and fuel. Locomotive, marine, standby, and continuous base load service leave very different wear signatures. So does the fuel the unit actually ran on.
- Check for liens, encumbrances, and pledge. Assets held against a debt cannot be cleanly transferred. This is a documentary check, not a technical one, and it is skipped far too often.
- Model the derate and the parts position before you sign. Calculate site rated output at real altitude, temperature, and power factor. Then confirm that spares for that specific engine variant are commercially available on a lead time your project can absorb. A cheap engine with a twelve month parts queue is not cheap.
USP&E performs this verification work as owners engineer for clients across the mining sector, utilities, and heavy industry. Our power plant engineering team runs the derate modelling and interconnection studies. Where an existing asset is worth saving, our power generation asset refurbishment practice scopes the rebuild. Where it is not, we say so.
Frequently Asked Questions
What are the EMD Diesel Generator Specifications for the 16-645E1?
The EMD SE16E1 stationary set, built on the 16 cylinder 645E1 roots blown engine, is published at 1,700 continuous engine BHP and 1,210 kW generator output at 750 RPM, and 2,100 BHP and 1,500 kW at 900 RPM. The 750 RPM rating corresponds to 50 Hz service and the 900 RPM rating to 60 Hz service with an appropriately poled alternator. Site altitude, ambient temperature, and power factor will reduce these figures in practice.
Are EMD 645 and 710 engines diesel or natural gas?
They are diesel engines. Both the EMD 645 and the EMD 710 are two-stroke compression ignition diesel families originally developed for locomotive service. Natural gas operation is only possible through a third party dual fuel conversion in which natural gas is admitted to the cylinder and ignited by a small diesel pilot injection. There is no factory EMD natural gas generator set product line, and any listing describing one should be verified before you proceed.
What is the largest EMD diesel generator set available?
The largest published EMD stationary generator set is the SE20G4C, a 20 cylinder 710 series machine rated at 5,000 continuous engine BHP and 3,580 kW at 900 RPM, or 4,155 BHP and 2,980 kW at 750 RPM. Larger plant capacity is achieved by installing multiple sets in parallel rather than by a single larger EMD unit. Projects above roughly 10 MW are usually better served by heavy frame medium speed engines or by gas turbines.
How long does an EMD diesel engine last before major overhaul?
Interval depends on duty cycle, fuel quality, load factor, and maintenance discipline rather than on a single published figure. Well maintained medium speed industrial diesel engines in continuous service commonly reach major overhaul at intervals measured in tens of thousands of running hours. The reliable answer for any specific unit comes from its own service history, borescope condition, and oil analysis trend, not from a generic number.
Can an EMD generator set be converted from 60 Hz to 50 Hz?
Frequency change on a medium speed reciprocating set is an engineering project, not a switch. It requires a change in rated engine speed, a matching alternator pole configuration, and revalidation of the governor, controls, protection settings, and driven auxiliaries. It is technically achievable on some sets and uneconomic on others. The determination requires a unit specific engineering assessment.
What does SE mean in an EMD model number?
SE denotes a Stationary Equipment Set, distinguishing land based generator set and mechanical drive packages from ME, which denotes a Marine Equipment Set. The prefix is significant because the same engine carries different published ratings in stationary, ships service, drilling, and propulsion duty. Always confirm which rating basis a quoted figure refers to.
Does USP&E supply and maintain EMD generator sets?
USP&E Global is an EPC and O&M contractor, meaning engineering, procurement and construction, and operations and maintenance. We provide owners engineering, inspection and condition assessment, refurbishment scoping, balance of plant design, installation, commissioning, and long term operations and maintenance for reciprocating engine plant including EMD assets. EMD units are not a permanent line in our diesel generator inventory, which is built principally around Caterpillar, Cummins, MTU, MAN, and Perkins platforms, so availability should be confirmed directly.
Summary: Key Takeaways on EMD Diesel Generator Specifications
- EMD 645 and 710 engines are two-stroke diesel engines. They are not factory natural gas machines, and gas operation exists only as a dual fuel retrofit.
- Published EMD Diesel Generator Specifications for stationary sets span 570 kW to 3,580 kW, or roughly 0.57 MW to 3.58 MW per set.
- Rated speed determines frequency. 750 RPM ratings serve 50 Hz markets and 900 RPM ratings serve 60 Hz markets, and the published output differs at each.
- Turbocharged F and G series sets deliver substantially more output from the same block than roots blown E series sets, at the cost of added overhaul scope.
- The same engine carries different ratings in stationary, ships service, drilling, and propulsion duty. A kW figure without an application and a rated speed is not a specification.
- Site altitude, ambient temperature, fuel specification, and emissions rules all move the usable rating away from the catalogue figure.
- Original hours, hours since overhaul, borescope condition, and a clean lien position determine whether a used EMD set is an asset or a liability.
The catalogue number is where the analysis starts, not where it ends. Across our project experience, every delivery begins by establishing what the equipment will actually do at your site, on your fuel, under your grid code, before a single dollar of capital is committed.
Ready to Power Your Project? Talk to USP&E’s Engineers Free.
USP&E Global offers a complimentary 4-hour engineering consultation for qualified power station, EPC, and O&M projects. Whether you are in early feasibility or ready to mobilize, our team of 350+ engineers across 35+ countries is ready to guide your project to success with speed and without excuses.
USP&E Global, Powering Possibility. Built for the Frontier.
ISO 9001:2015 | ISO 45001:2018 | 150+ Projects | 35+ Countries | Zero Lawsuits