Powering down

Powering down Alaris helps vessels find energy savings.

By Chris Dupin and Eric Kulisch

      Slow steaming is catching on as a common business practice designed to reduce fuel burn for ocean-going vessels.
      But going slower doesn't always make a ship more efficient. And the trend towards shore-side electrification to run ship systems while at berth doesn't mean ports are always cutting down on pollution.
   Those are the conclusions of Mike Gaffney, executive vice president of Alaris Cos. LLC, a Petaluma, Calif.-based firm    that specializes in shipboard energy management.
      The high cost of bunker fuel and the international community's push to reduce greenhouse gases is placing a premium on energy efficiency for companies that operate commercial vessels and creating new opportunities for Alaris.
      That's because achieving an optimal level of efficiency while saving money isn't necessarily an intuitive exercise. Many companies on terra firma utilize energy management programs to eliminate waste, but most vessel operators do not have a systematic way to analyze their energy use.
      Saving money and minimizing the risk of future emissions violations requires careful financial and technical analysis of a ship's operating systems and how they consume fuel. The analysis can be done on each piece of equipment or an overall system.
      Slow steaming has grown in popularity the past couple of years as bunker fuel prices shot up above $500 per ton and freight demand tailed off. Some carriers are not only slow steaming, they're moving to 'super-slow steaming' in which vessels are operated at speeds as low as 12 knots.
      But slowing ships down too much might knock them off their efficiency curve and end up consuming more energy, Gaffney said in an October presentation to the International Propeller Club's annual conference in Seattle. Finding the optimal speed from the standpoint of energy use depends on the relationship between hull speed and engine efficiency.
      'You need to plot that out because sometimes slowing down too much can actually decrease your efficiency and make your carbon footprint worse,' he said.
      Advocates of shore-side electrification argue that it eliminates the dirty practice of operating diesel auxiliary engines to run refrigeration, lighting, computers, pumps and other power-hungry systems on a ship, thereby improving air quality in and around ports. Cold-ironing, as the practice is referred to in the maritime industry, may only end up transferring the emission zone from one area to another, according to Gaffney.
      'A lot of times when you plug a ship in, you're actually using more energy shore-side, and if you have coal-fired plants you're increasing emissions because you're using more energy,' he said.
      The cold-ironing concept deserves more study because it works well in ports such as Seattle that have lots of hydro-electric power, but less so in places such as Norfolk that depend on electricity from coal-fired plants, he declared.

Mike Gaffney executive vice president, Alaris
'Sometimes slowing down too much can actually decrease your efficiency and make your carbon footprint worse.'

      Gaffney, a certified energy manager, said the maritime industry would get more bang for its buck by first reducing its energy requirements in port instead of building up electric energy infrastructure (ship modifications, substations and massive power cables) to meet current wasteful operations.
      Ships are designed for being at sea in worst case conditions so systems are oversized for most power loads in port, Gaffney said, pointing to the salt water pump for cooling the engine and fan for cooling the engine room as examples of equipment that are geared beyond normal operational requirements and not used judiciously.
      'A lot of energy is being wasted,' Gaffney said in an interview. 'Ships could realistically cut their loads in half by taking some practical steps.'
      Load leveling allows systems to cycle off when not in use so that energy is efficiently delivered to another system with a critical load. The concept is to keep energy use constant by stopping energy flow to components of a system that don't need it and supplying cooling, heating or electricity to equipment at peak demand times ' and in only the amount that is needed.
      Many types of equipment, such as heavy oil purifiers, that aren't needed while in port are usually kept operating, Gaffney said. Ships also run saltwater pumps at maximum capacity regardless of the requirement.
      Incorporating ice storage systems is one method of leveling loads, according to Gaffney. When the galley opens to prepare the next meal, for example, it adds to the power demands of the vessel. Instead of continuing to power the air conditioning by drawing on a diesel generator or shore power, the cold from the ice system, which stores energy in the form of ice during low demand periods, can be transferred to a special liquid and put through the air conditioning system.
      Turning systems on and off requires additional work and which may require a tradeoff between increasing labor hours or saving energy, especially with smaller crews on modern vessels.
      Gaffney, a former chief engineer on the APL Singapore, said using automation and variable drives eliminates the manpower issue.
      Load leveling ' equivalent to rolling blackouts by utility companies in the summer ' can also be used at sea to reduce the size of generator required or operate at peak efficiency.
      If all the loads are operating at once, it can overload one generator and require two to be online versus a normal load that can be handled by one machine.
      By reducing the power loads and energy requirements of various systems, companies can save money at sea or in port, Gaffney said.

What's An Energy Audit? Alaris, in addition to performing energy audits and making recommendations on how ships can reduce operating costs and carbon emissions, also provides other marine engineering and ship management services for crews and shore-side personnel.
      The five-year-old company has two additional chief engineers who are certified energy managers and three more who are preparing to receive certification.

Bobbi Wolff CEO, Alaris
'There are so many companies out there selling something that are making claims ' if you believe everything that everyone said the ship would eventually be producing fuel.'

      Co-founder and Chief Executive Officer Bobbi Wolff said the company is working with about 10 companies to prepare audits. Customers have included companies that manage vessels for government agencies such as the Maritime Administration and Military Sealift Command, as well as private companies such as Foss.
      The audits generally cost about $25,000 to $100,000 to perform and the findings can often be applied to several ships. The firm also performs energy audits for terminals.
      While the economics of the shipping industry have changed dramatically over the past two years, Wolff said engaging companies in energy conservation remains a tough sell.
      'A couple of years ago if you told a shipping company you could save them $1 million they didn't care,' because firms were making so much money, Wolff explained. 'Now $1 million is a lot of money and they are interested, but don't have the money to invest even if a survey may give them $1 million in savings.
      'The other thing that makes it difficult is that there are so many companies out there selling something that are making claims: 'You are going to save 15 percent,' 'you are going to save 10 percent' ' if you believe everything that everyone said the ships would eventually be producing fuel,' she joked.
      In Seattle, Gaffney called for the government to extend the Energy Star program, which helps consumers understand which appliances meet the strictest energy standards, to shipboard equipment and vessels. That would help engineers make decisions when replacing equipment rather than simply relying on the high efficiency claims of manufacturers.
      Gaffney also urged the Department of Energy to speed up expansion of its SmartWay program for trucking and rail to the maritime sector so shippers have a standard by which to judge whether their carrier is using green ships. Many retailers and other shippers have made environmental stewardship a core part of their branding strategy and are trying to reduce their carbon footprint.
      SmartWay assists shippers and carriers in measuring the impact of their transportation operations on the environment, and identifying products and best practices for reducing fuel use and air pollution. Shippers in the program commit to using SmartWay carriers whenever possible.
      Pilot programs that validate and certify which technologies provide a good financial return would also help the maritime industry, Gaffney added.
      Wolff said she hopes efforts by the International Maritime Organization to get the shipping industry to reduce greenhouse gas emissions give the audit business a boost.
      Other organizations such as the class society Det Norske Veritas say they have developed programs because of the IMO's efforts to reduce carbon dioxide emissions. DNV's 'Triple-E Environment & Energy Efficiency Rating Scheme' aims to classify ships roughly to how energy efficient they are.
      The advantage of having engineers on staff with experience working at sea, Wolff said, is that their recommendations are more likely to be implemented.
      'They speak 'chief.' They understand what engineers are up against in their main mission, which is to get a vessel from here to there,' she said.
      'A lot of shore-side companies don't understand the dynamic environment on a ship. A building is static ' it stays still and conditions don't really change that much. But on ships you have to take into account all the different conditions. The ship could be discharging cargo, maneuvering, it could be plugged in, the ship may be at a different draft, operating in different weather.'
      'There are many systems that are all connected on a ship that you don't see on shore side,' explained Gaffney. 'If you go to a facility like a hospital, you typically have heating, ventilation, air conditioning and some plumbing, but you don't have a diesel engine. Your power comes from the grid. On a ship you're both your power supplier, the grid supplier, and you have all the consumers and it's very dynamic because the ship is moving all over the world and constantly moving.'
      To perform a ship audit, engineers at Alaris will spend several weeks studying the ship, the equipment it has on board, diagrams for wiring and other systems, understanding how they are interrelated. They then go onboard a ship for a voyage with several suitcases of meters, clamping instruments on equipment and seeing how energy use varies when the ship is performing different operations.
      The company has a patent pending on a software tool called the Energy Quantification Utilization and Assessment Tool Electronic (EQUATE) it has developed for this work.
      Often the company is able to identify many easily obtained savings ' things like turning off lighting in cargo holds or closing doors to reduce air conditioning bills.
      'In many cases it's just a matter of going on board and talking to people and giving people an idea of the magnitude of what some of these operational changes mean. A typical organization will then take those ideas and take it to the next level and the program will just continue to grow and get better,' Gaffney said.
      Wolff and Gaffney gave several examples of vessel audits where they have identified savings:
      ' For a ferry on the East Coast they recommended 20 energy conservations measures that could be implemented at low or no cost, which resulted in annual savings of $300,000, or a 16 percent reduction in energy expenses, and a reduction of 2,038 metric tons, or 18 percent, in carbon dioxide emissions.
      ' Reduced the energy budget of a new tug-and-barge unit by $1.1 million, or 47 percent, and CO2 output by 7,560 tons. Gaffney said the company discovered that the optimal speed for the combined tug and barge was lower than the published speed for the tug engine. Taking advantage of slack time in the schedule, the ship saved $800,000 by slowing down while still moving the same amount of cargo.
      ' The company found a government cargo ship could reduce operating expenses by nearly $1.1 million and reduce CO2 by 7,808 metric tons by turning off equipment that was not needed or operating it
differently.
      'We've actually found in some cases that companies can only take so many recommendations, so we've stopped at 20, 25 of the top energy conservation measures because they can't implement more than that in a reasonable period of time,' Wolff said.
      The return on investment from upgrading to more energy efficient equipment varies depending on how good it is at reducing energy use.
      Gaffney said installing a variable frequency drive on cooling water pumps in many cases provides more than a 500 percent return within months.
      The company also noted it will sometimes identify measures that could save energy, but a company may not want to pursue them. For example, the company once recommended to a ferry operator that one of two engines on board could be shut down, but the company said it wanted to always have both engines operating.
      Gaffney believes that energy conservation needs to become a part of every ship engineer's training in the future. He recommends that the maritime academies incorporate the subject in their curriculum, not simply as an extra course or only in engineering classes, but even in economics classes where students learn about lifecycle analysis.