IMX Sessions Focus On Future Of Propulsion

With a look toward the future, participants in the virtual Inland Marine Expo (IMX) sponsored by The Waterways Journal September 29-October 1 talked about innovations in propulsion and held a roundtable discussion on putting hybrid to work.

Joshua Sebastian, engineering manager of The Shearer Group Inc., led the discussion on propulsion innovations, which included liquefied natural gas (LNG) and diesel-electric options as well as energy storage development. The Shearer Group also sponsored the session.

Sebastian began by speaking about major regulatory developments within the industry over the past couple of years. In October 2019, the Coast Guard adopted ASTM F3353-19 as guidelines for vessels with lithium ion battery installations instead of proceeding on a case-by-case basis. For natural gas use, the big change was that the Coast Guard adopted the International Code of Safety for Ships Using Gases or Other Low-Flashpoint Fuels (IGF code) in July 2017, Sebastian said. He also spoke about changes in propulsion options over the last 15 years, showing examples of six different propulsion variations on 2,400 hp. inland towboats as an example.

“There are just a myriad of options so we can now try to tailor the propulsion system to the exact needs of the vessel. It can improve performance, it can improve efficiency, and it can overall improve the product.”

Sebastian also gave details regarding current LNG towboat projects The Shearer Group is working on with SCF Marine Highway and SCF Container Express and talked about the need for more data on various systems.

Scott Myers, president of OptiFuel Systems LLC, talked about the state of LNG in the industry, noting that it has been used more in the rail sector so far. The rail market is increasingly moving away from dual fuel to 100 percent natural gas, he said, noting that in California and some other markets, the switchover helped meet toughened emissions standards and that dual fuel doesn’t save costs over time the way full LNG systems do.

Cummins has approved OptiFuel for rail and over the next three months will be doing so for marine EPA certifications, Myers said, creating a new engine market that includes no nitrogen oxides (NOx), particulate matter (PM) or carbon dioxide (CO2) emissions and products running on LNG, compressed natural gas (CNG) and renewable natural gas (RNG), Myers said. RNG is made from renewable sources like landfill gas or biomethane from digester operations.

The Cummins line of natural gas engines is available in up to 400 hp. currently and up to 500 hp. next year, he said.

Myers said although some people have been concerned about refueling LNG-powered engines, sufficient refueling technology is already in place in both the rail and marine markets, and conversion to natural gas comes with free installation of refueling equipment.

“The good news is it’s affordable,” Myers said, again turning to experience with locomotives to note that it now costs about the same to have a zero-emissions line-haul locomotive as it does a diesel one, and the fuel savings are between 20 and 40 percent.

Myers sees great potential in the marine market, which he noted is a very large market with more than 5,000 tugs and towboats in the United States and about 2,000 work/harbor/ferry boats. The average age of equipment in the marine industry is more than 25 years old. In particular, he said, the industry has potential emissions and cost savings converting the inland marine market to natural gas hybrid solutions by 2035 and using RNG blend as fuel.

“That’s where we’re now trying to focus our business as a company,” Myers said. The switch to natural gas could reduce operators’ average fuel cost by half, he estimated.

Use of the technology in the marine sector is already taking place in California because of strengthened emissions standards, he said, noting that the state is focusing on repowering commercial harbor craft to achieve zero or near zero emissions starting in 2023. That includes fishing vessels, ferries, excursion vessels, tugboats, towboats, crew and supply boats, work boats, barges and pilot vessels and dredges. Myers said this major change is likely to move to all 50 states eventually.

What will help make the conversion affordable is the Low Carbon Fuel Standard (LCFS) and Alternative Fuels tax credit programs being extended to rail and marine, providing a financial incentive for fleet owners to replace their equipment, he said.

Hybrid Systems
Peter Brooks, account manager for marine and port solutions at BAE Systems Inc., talked about his company’s HybriDrive Solutions hybrid electric propulsion systems for transportation and power management, noting that BAE is the market leader for heavy duty electric-hybrid propulsion systems both in the United States and Europe.

Brooks detailed BAE’s three core standardized systems, the HybriGen Power and Propulsion, HybriGen Assist and HybriGen Power, each of which are designed to meet different needs. An analysis by MJ Bradley of the HybriGen Power system showed it averaged a 25 percent reduction in fuel consumption, Brooks said, with total annual fuel savings estimated as much as 15,000 gallons. The system is also designed for improved reliability with greater than a 52,000-hour life, and he described it as nearly maintenance-free.

Dave Lee, senior account manager-new sales with ABB Marine & Ports, talked about battery and hybrid-electric towboats as one step on a pathway to carbon-free shipping. Another step is using fuel cells, and he noted that ABB will have the world’s first inland towboat with a fuel cell system in it next year. Eventually, he said, the industry is likely to focus on carbon-free hydrogen in shipping.

Lee also took a closer look at integrated diesel-electric workboat propulsion systems, saying that the electric is the most important part of diesel-electric systems as they “future-proof” the vessels, which can last 30, 40 or 50 years.

He also talked through what he called a battery revolution, saying the batteries available now can provide a spinning reserve with no need to have engines running “just in case”; peak shaving for bumping and holding, using the engines for true demand and not a short stressful burst; enhanced dynamic performance with instant power to supplement running engines; and strategic loading, utilizing an engine’s fuel curve to advantage.

Putting Hybrid To Work
Joe Hudspeth, director of business development for BAE Systems, Robert Kunkel, president of alternative marine technologies and the managing partner of Harbor Harvest and Micah Tucker, founder of design, engineering and construction management firm Tucker Yacht Designs spoke in a separate session on their shared experiences with putting hybrid to work for them, with Hudspeth introducing Kunkel and Tucker as well as serving as moderator. BAE Systems sponsored the webinar.

Kunkel detailed his experience with hybrid, beginning with working with Tucker on a teaching vessel for the Maritime Aquarium in Norwalk, Conn., that operates in Long Island Sound. The aquarium chose a hybrid system because they wanted something that would have no environmental impact or emissions as they taught environmental lessons and also be quiet enough for teachers directing the children in their activities, he said. The 65-passenger design allows for a school bus-load of children to be carried at one time. Harbor Harvest is also part of a marine highway designated project that transports farm products across Long Island Sound on hybrid catamarans.

Kunkel said he now has great confidence in the reliability of hybrid systems. “We’re literally coming down, disconnecting shore power, flipping a switch and taking off,” he said.

Tucker talked about systems available for owners and operators looking to reduce fuel costs and emissions, noting that a range of options is now available. One option is where an electric motor can be added to a diesel drive train as a boost function or as an optional diesel or electric functionality with a duel-input gear box or a gearbox with a PTI input with an electric motor on it. The diesel and electric systems can either work together or individually, he said. Another option is an electric motor directly driving a shaft line and propeller, powered either through a battery system or a battery and a generator option. A last option involves use of a hydrogen fuel cell supplementing the battery bank.

“That’s basically as clean as you can get because the only emissions out of there are pure water,” he said.

Hudspeth noted that BAE Systems is bringing the first hydrogen fuel cell-powered vessel into operation in America, a ferry that will go into service in San Francisco, Calif., later this year.

In response to a question, Tucker said most hybrid systems so far have been new builds for Coast Guard-inspected vessels, adding that few people have been interested in refits or repowers so far. In considering such systems from a boat builder or naval architect’s perspective, he said, an advantage is a range of design flexibility, as designers are not tied to the typical engineroom arrangement required for a diesel power plant. Instead of having a typical large engineroom full of equipment, he said, designers can split up and spread out equipment. However, he stressed it will be important to get the Coast Guard involved as early as possible before getting too far into the design phase to make sure designers don’t run afoul of any Coast Guard regulations as the Coast Guard adapts to the emerging hybrid market.