“Simply put, we as a military rely too much on fossil fuels. That dependence creates strategic, operational and tactical vulnerabilities for our forces and makes them susceptible to price and supply shocks caused by either man-made or natural disasters in the volatile areas of the world where most fossil fuels are produced.” — Secretary of the Navy Ray Mabus
What is the “Great Green Fleet”?
- In 2009, Secretary of the Navy (SECNAV) Ray Mabus announced five aggressive energy goals to reduce the Department of Navy’s (DON’s) consumption of energy, decrease its reliance on foreign sources of oil, and significantly increase its use of alternative energy.
- One of the five energy goals is to demonstrate and then deploy a “Great Green Fleet,” a Carrier Strike Group fueled by alternative sources of energy, including nuclear power.
- The Great Green Fleet is named in honor of President Theodore Roosevelt’s Great White Fleet, which helped usher in America as a global power on the world stage at the beginning of the 20th Century.
Why is the Navy doing this?
- SECNAV’s goals are designed to not only help save the US Navy money in the long run, but to make us more safe through decreasing our reliance on foreign sources of fuel.
- The SECNAV’s goals, in addition to the Great Green Fleet, include:
- By 2020, 50 percent of total DON energy consumption will come from alternative sources.
- By 2020, DON will produce at least 50 percent of shore-based energy requirements from alternative sources; 50 percent of DON installations will be net zero.
- By 2012, DON will demonstrate a Great Green Fleet in local operations and sail it by 2016.
- By 2015, DON will reduce petroleum use in the commercial vehicle fleet by 50 percent.
- Investments in an alternative to foreign sources of fuel will help the Navy and the nation become less dependent on foreign oil, and less subject to volatility in oil prices that can directly affect our readiness.
- Price hikes resulting from last year’s instabilities and other market forces left the Department of the Navy this year with an additional nearly $1 billion bill for fuels.
- To pay this added cost, we transferred funds from our Training and Readiness budget.
- That means that our Sailors and Marines fly less, steam less, and train less.
- This is not an insubstantial expense, and we cannot, and should not, keep trading readiness for fuel.
- The Navy views energy as a resource that must be conserved efficiently so that we can extend our range and reduce our fuel tether, making us more agile and more combat capable.
When will the Navy be sailing the “Great Green Fleet”?
- The Navy plans to deploy the “Great Green Fleet” sometime in 2016.
How is this fleet “Green”?
- The ships and aircraft will be powered by alternative fuel, either nuclear or advanced biofuel blends.
- The biofuel blends are 50-50 mixtures of biofuel (made from animal waste fat and algae) and petroleum-based marine diesel or aviation fuel.
- Navy surface ships will be powered using 350,000 gallons of hydroprocessed renewable diesel (HRD-76) blended with an equal amount of marine diesel (F-76).
- Navy aircraft will burn 100,000 gallons of hydroprocessed renewable jet fuel (HRJ-5) blended with aviation fuel (JP-5).
- These ships, and others worldwide, have been utilizing “Smart Voyage Planning Decision Aid (SVPDA), a computer software application that will be used by the Navy’s Fleet Weather Centers in Norfolk and San Diego to push optimized ship routes to all Navy ships for both maximum fuel efficiency and safety.
- SVPDA reduces energy consumption by exploiting real-time knowledge of the physical environment including:
- Ship-specific hydrodynamic and propulsion data
- SVPDA capitalizes on real-time data and computing power to plot routes with the potential to save 3% across the Fleet in annual fuel costs.
Is the Navy doing anything else to be “Green”?
- The Navy is doing several things to help its ships and commands become far more energy efficient.
- It is establishing “Energy Dashboards” aboard ships:
- Energy Dashboard is a shipboard tool that provides the Sailor with real-time situational awareness of the energy demand associated with equipment lineups and mission.
- Energy Dashboard uses the Integrated Condition Assessment System (ICAS) to collect data from shipboard equipment.
- The Energy Dashboard includes the Fuel Management System (FMS), which assists pre-underway planning by recommending efficient equipment lineups.
- Energy Dashboard calculates and instantly displays daily energy consumption rates.
- It is implementing Solid State Lighting aboard ships and facilities:
- Light Emitting Diodes (LED) are replacements for incandescent and fluorescent lighting fixtures.
- SSL lamps are arrays of individual LEDs producing light at the same quality and brightness as legacy lamps with an increased lifespan.
- Incandescent and berth lights will be replaced with fixture-form-fit-function SSL bulbs, and legacy fluorescent tubes will be replaced with SSL tubes.
- SSL improves energy efficiency, saves fuel at-sea and saves shore power in-port.
- SSL also improves lamp lifespan, and drives down maintenance and sparing costs.
- Removal of mercury-containing fluorescent tubes drives down handling and storage costs.
- The Navy has been working to update Navy ships with a new Gas Turbine Online Water Wash:
- Currently, U.S. Navy surface ship gas turbine generators and main propulsion engines are periodically shutdown and washed to improve compressor performance and extend operating life.
- The online water wash system allows the compressor wash to be performed while the engine is in operation.
- This extends the period between offline washes and improves performance in the interim.
- Online water wash will reduce maintenance, improve starter life and reduce fuel consumption by extending the time between offline washes and keeping the compressor section of the gas turbine cleaner in the interim.