Q: How many San Francisco Bay Ferries use Cummins diesels?

A: The Golden Gate Ferry is the first high speed ferry to use Cummins engines. In addition, the Oakland/Alameda Ferry just ordered a new ferry with Cummins engines. Incidentally, Cummins engines are used in Boston Harbor and other sites throughout the world.

However, Cummins engines power approximately 25% of the workboats on the bay and Cummins engines are used almost exclusively in the Gulf of Mexico for the large crew and supply boats operating there. Cummins engines are also widely used in the commercial fishing industry throughout world.

Overall, Cummins is the world’s biggest producer of diesel engines over 200 horsepower, which amounts to about half a million engines per year. And we’re rapidly becoming the industry leader in CNG engines as well.

Q: Russell Long of the Bluewater Network says your engines, person for person, create ten times the air pollution a single-occupant automobile. Is he right?

What I want to stress above all else is how much we want to work with the environmental movement. We are making a major push in CNG and LNG engine technology and are second to none in being able to show environmental progress generally. Indeed, I don’t see Russell Long as a critic, I see him as a partner.

But I think what Russell Long did with his study is to compare apples and oranges by using obsolete diesel engines in coming up with his numbers. The engines we’re installing today simply can’t be compared with the engine Russell used in his study. Another important factor Russell overlooked is the "stop and go" of the car versus the "steady state" operation of the ferry, which is a huge factor when comparing the two.

Keep in mind that the new ferries presently being constructed will use only about 0.2 of a gallon of diesel fuel to move one passenger one-way. If you compare this to a car making the approximately 22-mile trip into the city to the ferry building, that car would conservatively use at least 1 gallon of gasoline (assuming mileage of 20 miles per gallon average car, let alone SUV’s which get far less).

Looking at it another way, an average car engine is in the neighborhood of 300 cu. inches. The new ferry will have four 3,000 cu. Inch engines or 12,000 cu. inches in all,. To be sure that’s forty times the cubic inches of a car but remember that the ferry will carry 400 times the number of people as a single occupant car.

But again, proud as I am of our progress, we have lots more work to do and I look forward to meeting regularly with Russell Long and his people to compare notes.

Q: Can you explain in layman’s terms why environmentalists are concerned about diesel engines? Are their concerns valid?

A: Of course their concerns are valid, but there is debate because there are many acknowledged benefits of diesel fuel. For example, diesel fuel has such low CO2 (carbon dioxide) and excellent fuel economy when compared to other fuels that it is arguably better over all for the environment.

Environmentalists are concerned, just like we are, because there are indeed elements in diesel exhaust that aren’t good for the environment. But many of these same elements are in gasoline exhaust, too, and they, too, can be dangerous depending on exposure time and unit risk factors, meaning how long you are exposed to how much. Keep in mind; this is true with alternative fuels (i.e. natural gas) exhaust, also.

What I think gets lost sometimes is the unparalleled progress we’ve made cleaning up diesel emissions. Consider:

Nitrous Oxides Nox - Reduced 75%

Particulate matter - Reduced 90%

Hydrocarbons - Inherently low already in diesel

Carbon Monoxide - Inherently low already in diesel

And Cummins continues to work with the EPA, California Air Resource Board and various Air Quality Management Districts to do even better.

Q: Do diesel emissions present any kind of potential health hazard for ferry riders? What about the ferry workers, who ride the ferries all the time?

A: The best people to determine the answer to this question are the folks doing the health research. Cummins, along with other engine manufacturers, funds independent health research with the EPA, the Health Effects Institute in Cambridge, Mass. and the Natural Environmental Respiratory Center in Albuquerque, New Mexico.

I imagine any research we, the engine maker, did would be considered tainted, so it is best and independent group do the data and we then work with the results.

Q: What are you doing to make diesel engines environmentally friendly? How will this affect ferry riders (will fares have to go up?

A: Well, it’s an ongoing effort and it gets kind of technical. For starters, we’re working on what’s called full authority electronic engine controls and in-cylinder improvements to increase performance and efficiency. Then there’s exhaust after-treatment and exhaust gas re-circulation. Lower sulphur fuel and other alternative fuels are also on the way.

Q: How much does a tune-up for a ferry run?

Well, Jiffy-Lubes won’t take ferries if that’s what you mean. A tune-up for a ferry is referred to as "running the overhead" which refers to re-setting the valves of the engine for maximum performance and minimum emissions. It’s done every 2,000 hours or twice per year and costs about $2,000.

Q: What’s the mileage? How much fuel, say, does the Del Norte use going one-way from Larkspur to San Francisco?

A: I don’t know about the Del Norte specifically, but the Cummins engines will use about 80 gallons of diesel fuel for the one-way trip.

Editors note: our information is that the current engines on the Del Norte require approximately 160-180 gallons per one-way trip. Reducing fuel usage would, obviously, reduce emission output.

Q: Should maritime engines remain exempt from environmental laws?

A: No. Cummins supports stringent, but fair and achievable emissions standards for all engines in all applications.

Q: Are diesel engines here for the long-term, or do you think they will eventually give way to compressed natural gas (CNG) technology?

It depends on what you mean by long term. If long term means the next 10 to 15 years, then I personally believe that you will see cleaner and cleaner diesel engines operating on cleaner and cleaner diesel fuel. I also believe there is no one answer. The alternative fuels such as natural gas will come more and more into play in applications where it makes practical sense; we are already seeing how a diverse strategy will help us make huge clean air gains over-all.

Q: Is Cummins developing CNG or other types of new engine technology?