Sunday, November 01, 2009

Navy Incentives to save fuel

I realized that I didn't pay enough attention to the US Navy’s innovative solutions to fuel consumption challenges. That is why I decided to compile some information on that issue. Here is my preliminary report.

Navy's Energy Conservation (ENCON) efforts seeking cost savings or avoidance have been in place for some time now. There are two major programs.

(1) Naval Sea Systems Command's (NAVSEA's) Incentivized Energy Conservation (i-ENCON) Program.
(2) Fleet Readiness, Research and Development Program (FRR & DP).

The Navy i-ENCON program

The Navy i-ENCON program is a hands-on "meet the fleet" initiative that routinely meets with ship operators to review specific fuel-saving operational procedures. It's committed to reducing ships' energy consumption by 10 percent each year by providing ships' commanding officers and masters and ships' chief engineers energy-saving strategies and techniques and operations modifications. The strategies include "smart steaming," obtaining maximum fuel efficiency without impairing mission objectives. Techniques revolve around operating only the systems needed to support the mission, proper placement of ships' cargo and ballast to achieve balanced weight distribution, and more. Program sponsors recommend quarterly awards for ships with the most fuel-efficient operations.

One of the ways i-ENCON measures fuel and cost avoidance is through underburn, the reported fuel rate for the quarter that's below the ship class' average burn rate.

The motto is simple: Saving fuel and finding ways to cut back on fuel consumption through incentives saves money.

Ship Crews Find Fuel Conservation A Rewarding Experience. i-ENCON program is an effort where ships are recognized for submitting fuel conservation ideas that show results. Every year ships submit Secretary of the Navy (SECNAV) Energy Conservation Award write-ups, These write-ups include how they save fuel, how much they save fuel and what actions they took. The i-ENCON team evaluates them. The best ideas from the top eight ships, four ships from each hull configuration, are selected and recommended for the SECNAV's award.

The SECNAV ENCON awards are made annually to ships in two categories:
Large Hull - Crew of 400 or more and significant energy efficiency
Small Hull - Crew of less than 400 and significant energy efficiency

To encourage surface ships to reduce the fuel they use, the Navy is offering serious cash to ships for implementing cost avoidance measures. i-ENCON rewards leading fuel conservers among underway surface ships with special recognition and cash incentives. The top prize is $67,000, which commanding officers can use any way they want. Any ship that spends at least 96 hours underway per quarter is eligible for the prizes. Award winners are authorized to fly the SECNAV Energy Flag for a period of one year.

In fiscal 2008, the Navy saved $136 million in energy costs. According to i-ENCON Program Manager Hasan Pehlivan, the program helped Navy ships save more than 1 million barrels of oil in fiscal year 2008, (1.1 million barrels of fuel) enough to fill the 12-gallon gas tanks of more than 3.5 million cars resulting in a record cost avoidance of more than $136 million. In FY 2008, 148 ships received incentive cash awards, a total of $2 million. Award money is routed to each commanding officer's discretionary funds, which are often used to buy items like damage control gear or to augment the ship's welfare and recreation programs.

Naval Sea Systems Command announced 18 February 2009 (i-ENCON Program Realizes Record $48M Fuel Savings) that Navy ships realized a record of more than $48 million in fuel cost avoidance during the first quarter of fiscal year 2009.

Among the ideas Pehlivan shares are: shutting off the main propulsion system at night when ships are waiting for the next day's mission. By keeping the electric plant operating for what he calls "hotel loads," showers, lights, etc., a ship can see fuel savings of upward of 70 percent. "It's amazing savings. That's number one," Pehlivan noted. On ships with gas turbine and diesel engines with twin screws, they have the option of using only one scew--one shaft, one propeller, for driving the ship, Pehlivan said. That effort can result in a 50 percent fuel savings.

The destroyer Porter, based in Norfolk, Va., received $34,000. Porter spent as much time as possible underway last year using only one propeller, Feyedelem said, or running both screws with just two of its four gas turbines. The ship got to the point that even when it was going in and out of port, the crew would wait until the last possible moment to power up all four turbines, then power down the extras as soon as it was safe. The only other time it always kept all four turbines running was during underway replenishments, so it could break away from the other ship even if an engine failed. (source)

Cleaning the hull and propeller can result in a significant cost avoidance. A clean hull gives you a 12 percent cost avoidance. A clean propeller gives you 6 percent cost avoidance,according to Pehlivan. Maintaining machinery also results in fuel savings for ships.

Navy ships account for roughly 40 percent of logistics fuel consumption, that is fuel used to move something. To make ships more efficient at sea, Navy has focused on two major areas: better hull coatings and better hull forms, and hybrid electric drive to provide greater operational capabilities by allowing ships to operate longer without refueling.

Navy ships typically run two generators simultaneously to provide shipboard power requirements, with one acting as an emergency back-up for possible power loss. The uninterruptable power supply would allow ships to routinely run one generator. Only running one generator at 70 percent load versus two generators at 35 percent load saves about 10 percent of the fuel, somewhere on the order of six to seven thousand barrels of fuel a year. (Navy Innovation Reduces Fuel Consumption at Sea)

Fleet Readiness, Research and Development Program

This program aims at helping Navy ships, including MSC ships, to conserve fuel now and to find long-term fuel reduction solutions that enable us to meet mission requirements even when fuel prices go through the roof.

One of the initiatives is stern flaps for dock landing ships and multi-purpose assault ships that could yield annual cost avoidance of around $6.3 million. Stern flaps, projecting parallel to the water from the ships' transoms, would make the ships more hydrodynamic, which would reduce the energy needed for propulsion.

An article of Office of Naval Research Corporate Strategic Communications in June 2009 stated that new hull coatings being developed by the Office of Naval Research are showing promise in reducing the build-up of marine crustaceans – namely barnacles – on ships' hulls, optimizing vessel performance and dramatically reducing fuel costs. Marine growth adds weight and increases drag reducing a vessel's fuel efficiency. The practical problem for ships is simply that biofilm can add up to 20 percent drag and barnacles more than 60 percent. This increases fuel consumption and green house gas emissions. ONR-sponsored biofouling prevention coatings provide an environmentally safe alternative for protecting naval ship hulls, which could also benefit the commercial shipping industry.

The Naval Surface Warfare Center at Carderock estimates that biofouling reduces vessel speed by up to 10 percent. Vessels can require as much as a 40 percent increase in fuel consumption to counter the added drag. High-performance naval warships and submarines rely on critical design factors such as top speed, acceleration and hydroacoustic stealth. Previous biofouling prevention methods used toxic coatings, or biocides, to clear barnacle colonies from the ship exteriors. Although effective in the short-term, biocides exact a heavy environmental burden.

The question was why some marine animals, such as whales, harbor barnacles and others, such as sharks, stay relatively clean. Brennan discovered that the unique pattern of shark skin contributed to its ability to fend-off microorganisms.

Navy Stern Flap Installations Project to Save Millions in Fuel Costs

The U.S. Navy began installing stern flaps in April 2009 on amphibious ships in an effort make ships more fuel efficient and save up to $450,000 in fuel costs per ship annually. USS Whidbey Island (LSD 41) was the first dock landing ship to receive stern flaps.

According to Petter Kristiansen (FRR&DP program manager) "A stern flap, located on the aft end of a ship, makes the ship more hydrodynamic, reducing drag and the energy required to propel them through the water. Previous installations on other Navy ships generated annual fuel savings of $365,000 to $450,000 per ship."

Once installed fleetwide on both LSDs and LHDs, the initiative is expected to yield an annual cost avoidance of approximately $6.3 million, based on fuel oil costing $96 per barrel.

FRR&DP's Underwater Hull Coatings initiative

The marine fouling such as barnacles that accumulate on ships is a typical problem which causes hydrodynamic drag and reduces fuel efficiency. Colonized barnacles and biofilms on the hull of a Navy ship translate into roughly 500 million dollars annually in extra maintenance and fuel costs that are required to keep ships free of barnacles, oysters, algae and other marine life. But cleaning and recoating ship hulls is expensive and time-consuming, and recoating can only be done while a ship is in dry dock. The Naval Surface Warfare Center at Carderock estimates that biofouling reduces vessel speed by up to 10 percent. Vessels can require as much as a 40 percent increase in fuel consumption to counter the added drag.

New underwater hull coatings applied in to the guided missile destroyer USS Cole (DDG 67) are projected to save more than $180,000 in fuel costs per year. (USS Cole (DDG 67) Sports New Fuel-Saving Hull Coating). The new coatings will help reduce marine bio-fouling, build-ups of tubeworms, mussels, barnacles and other shell organisms on the ship's hull, according to Petter Kristiansen, program manager of the Fleet Readiness Research & Development Program (FRR&DP).

The new process is reported to use a fouling-release coating system. It is a silicone-based, non-toxic technology that provides a very smooth, slick, low friction surface. Settling marine organisms like barnacles, tunicates and algae can't attach themselves firmly to the slick surface.

In September 2009 the new underwater hull coating was applied to USS Port Royal (CG 73). Testing will assess fuel cost savings for the ship while underway.(First Cruiser Sails with New Fuel-Saving Hull Coating). The process uses a fouling-release coating system.

The initiative aims to apply new anti-fouling hull coatings on Arleigh Burke-class destroyers and Ticonderoga-class cruisers. Once fully implemented on the 70-plus active ships across the two classes, the program could potentially deliver fuel consumption cost avoidances of more than $12.6 million per year, based on fuel oil prices of $100 per barrel.

Autonomous Underwater Robot Maintains Naval Commitment to Environment

The Naval Materials Division of ONR´s Sea Warfare and Weapons Department is sponsoring the research on environmentally safe antifouling solutions which is developing this innovation -- an autonomous underwater hull grooming robot. ONR recently conducted tests with a developmental ship hull grooming robot, called the Robotic Hull Bio-inspired Underwater Grooming tool or Hull BUG. The tests showed that this little groomer — similar in concept to a autonomous robotic home vacuum cleaner or lawn mower — has a lot of promise.

The robot incorporates the use of a biofilm detector that utilizes modified fluorometer technology to enable the robot to detect the difference between the clean and unclean surfaces on the hull of a ship. Used to groom ships in port, the Hull BUG removes the marine biofilm and other marine organisms before they get solidly attached. This is especially important because Navy ships spend more than 50 percent of their service life in port, giving barnacles and marine life ample time to become settled and, if allowed, to further colonize and grow on the ship´s hull. While originally focused on reducing the use of toxic antifouling hull paints, these investments have also yielded technology breakthroughs that reduce the use of fossil fuels. Partners in ONR´s development of the Hull BUG include NSWCCD, SeaRobotics and the Florida Institute of Technology.

Military Sealift Command conservation efforts[1]

Fuel economy within the MSC fleet is impacted by two major factors — operational requirements and engineering plant operations.

Operational efficiencies

“MSC's Naval Fleet Auxiliary Force is being driven hard to supply Navy combatants spread out all over the globe. Operational commanders typically require NFAF ships to deliver across great distances quickly. The mission may require the replenishment ship to use 7,000 barrels of fuel to deliver 18,000 barrels to the customer. That's not very efficient, but the mission has to come first. When operations permit, we automatically shift to most economical hull speeds. We've issued a table that lists those speeds to all our ships. The values in the table are based on years of data collection, operational trend analysis and best shipboard practices. For instance, the most economical speed for fleet replenishment oilers, ammunition ships, dry cargo/ammunition ships and combat stores ships is 14 knots. For tugs it's 13 knots when not towing anything. Rescue and salvage ships, when not towing, do best at 12 knots. Fast combat support ships, on the other hand, do their best at 16 knots, while hospital ships are most economical at 7 knots. Other underway techniques include bottom and propeller polishing and use of the newer, super-slick bottom paints that reduce drag.”

Power plant efficiencies

“Efficient engineering plant operations depend primarily on proper maintenance. Keeping heat exchangers, air and fuel filters, and after coolers clean leads to better thermal transfer, more efficient fuel burning, and less wear and tear on the cylinder liners. In the Prepositioning Program, most of the fuel we use is for power generation. Much of the time, our Prepositioning ships are anchored or in port, waiting for tasking orders. However, while not sailing, they do still have to maintain the combat equipment they carry at the temperatures and humidity levels specified by our customers. That requires air conditioning, which takes a great deal of power from the ships' generators.

Studies have proven that operating one diesel generator at 80 percent load is much more efficient than operating two at 40 percent. It's the way diesels are designed. Our prepositioning ship masters routinely run only those generators needed to meet power needs while operating at about 80 percent load. Of course, when at anchor, there aren't any propulsion needs, but when sailing, if one engine can be shut down and the second engine can run at 80 percent load without affecting the mission, then more savings are generated.”

USMC Energy Summit on 13 August 2009

Commandant of the Marine Corps, Gen. James T. Conway along with Raymond E. Mabus, Secretary of the Navy, hosted and headlined a one-day USMC Energy Summit on 13 August 2009. The purpose was to raise awareness and understanding of what the Marine Corps is doing to lessen energy consumption and dependence on fossil fuels and inform people what the Corps’ is experimenting with, and what the greatest challenges will be.

A Marines news piece on August 14, (Marine Corps sets vision to conserve energy) reported the followings;

“The Marine Corps is doing a two-tier approach,” Conway said. “We talk about net zero – wanting our installations to produce as much energy as we use.” Conway said two Marine Corps installations, Marine Corps Air Station Miramar and Marine Corps Logistics Base Barstow, already have programs in place to help reduce the use of energy while producing their own through solar power and obtain “net zero” status.

Mabus said it’s important for the military not to depend on oil, and the military spends too much time using oil to get oil. “Only 10 percent of our energy is used by combat vehicles,” Mabus said. “A good portion of the other 90 percent is used is to get the combat vehicles their supplies. We simply have to have a better source of energy for our military than what we have today. We must move away from oil.”

[1] Robert D. Reilly Jr., Rear Admiral, U.S. Navy, Commander, Military Sealift Command, Rising fuel costs mean fuel conservation challenges, Sealift Magazine, August 2008.



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