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The U.S. Navy's Less Than Great 'Green' Fleet Development

John Miller's picture
Owner-Consultant Energy Consulting

During my Corporate career I provided manufacturing with power generation facilities’ technical-operations services and held different technical and administrative management positions.  In order...

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The U.S. Federal Government strongly supports green energy policies to displace fossil fuels. Is the Navy’s recent ‘Great Green Fleet’ initiative a sound and cost-effective action towards significantly reducing U.S. fossil fuels consumption and associated carbon emissions compared to existing alternatives?

The U.S. Navy (USN) began developing its ‘Great Green Fleet’ (GGF) initiative shortly after Obama’s presidency began. The GGF initiative includes the USN’s new energy goal to reduce petroleum consumption by 50% in 2020 by switching to alternative green energy sources including advanced biofuels and renewable electric power. While the use of solar PV to displace backup power generation fueled by petroleum is likely a reasonably sound clean energy strategy, substituting advanced biofuels for petroleum marine fuels has been very expensive, with highly questionable environmental benefits.

This USN green energy strategy is supposed to be consistent with President Obama’s position that “there is no greater threat to U.S. Security than Climate Change”. Unfortunately, the U.S. has recently faced increasing world-wide instabilities and growing security threats from countries and groups totally unrelated to greenhouse gas (GHG) emissions. Actual and increasing security threats include growing terrorist attacks in the Middle East and Europe, Russia’s Crimea invasion and Eastern EU insurgency ambitions, Iran’s likely growing support of terrorists and questionable UN nuclear agreement compliance, and China’s unlawful occupation of the South China Sea. These recent developments appear to be much greater and immediate security threats than developing climate changes.

In 2011 President Obama began issuing a series of announcements indicating that the United States would be expanding and intensifying its already significant USN presence in the Asia-Pacific; to possibly counter China’s occupation-militarizing buildup within these international waters. Such an action would require significant increased presence of the USN fleet forces in the Asia-Pacific in addition to their current world responsibilities; the Americas Pacific/Atlantic Oceans, Europe-Mediterranean Sea, etc. In light of past-and-developing security challenges and evolving-new military strategies in recent years, is the Administration’s GGF energy goals to effectively reduce the USN’s petroleum fossil fuels consumption reasonably feasibly and supportive of its growing responsibilities? To begin answering this question let’s start with reviewing the USN GGF initiative in more detail.

Following the Navy’s GGF initiative implementation to displace petroleum with alternative fuels they initially paid up to $400 per gallon for advanced biofuels. While this enormous clean energy cost rapidly became the subject of major program criticisms, the Department of Defense defended the initial cost as developmental and key to making the GGF independent to fossil fuels in the near future. Totally overlooked in this debate was the fact that the initial ‘algae’ based advanced biofuels had hugely negative ‘net energy values’ (NEV). Having highly negative NEV’s means that these developing USN advanced biofuels consumed far more, or initially many-times the fossil fuels during their ‘full-lifecycle’ production-thru-consumption than the petroleum fuels displaced. In other words, the net carbon emissions were many times greater than the fossil fuels displaced.

Fortunately, due to a combination of generous Federal Government subsidies and hundreds of millions in Government funding to a couple Private Production-Refining Companies, the cost of marine biofuels has dropped to a couple dollars per gallon or about 50% greater than average petroleum marine diesel market costs. Unfortunately, no credible analyses of the actual full-lifecycle NEV’s or carbon emissions appear to have been completed to verify if these latest and much cheaper GGF advanced biofuels actually benefit the environment or future global warming. Yes, biofuels made from waste materials such as animal fats could feasibly reduce full lifecycle carbon emissions by up to 50% compared to the displaced petroleum fuels. However, the actual impact depends on the level of fossil fuels consumed in the full lifecycle’s ‘supply chain’ from production through consumption. Unlike on-road biodiesel that has an existing, reasonably efficient supply chain infrastructure to transport, blend and deliver this successful biofuel throughout most the U.S., the GGF’s developing advanced biofuel system is new and generally segregated from existing marine fuels supply chains and infrastructures. This leads to likely very inefficient operations (increased fossil fuels consumption) compared to existing marine fuels supply chains, which significantly compromises the full lifecycle carbon reduction benefits of this relatively unique-new biofuel. Not only does this significantly increase the full actual and sustainable costs of GGF blended biofuel-diesel marine fuels, but this also directionally minimizes the availability and environmental benefits of the overall program. Current GGF advanced biofuels have generally limited access to the USN via U.S. West Coast ports.

The net result of the unique and very limited access to GGF advanced biofuels is to make the original Navy program’s goal of reducing total petroleum fuels consumption by up to 50% in 2020 extremely unlikely-to-infeasible; despite the very high costs compared to existing petroleum supplies. The claimed environmental benefits are also substantially less than available-more feasible alternatives.

Reducing the USN’s GHG emissions by displacing petroleum marine fuels with advanced biofuels is a noble effort, but unfortunately is far less efficient compared to available alternatives. A major problem the USN has and will increasingly face is the fact that its available funds (approved Congressional Budget) is limited, its need for military resources continues to grow (due to increased terrorist, Middle East, Russian, Chinese, etc. threats) and the fact that the total U.S. fleet size/capability continues to decline. Since USN funding resources will very likely continue to be constrained in the future, wasting significant funds on developing the GGF advanced biofuels vs. more cost effective alternatives is generally very poor government, national security and likely climate change-related policy.

Rather than wasting available-limited funds on very inefficient and likely ineffective military marine advanced biofuels, the USN should shutdown this part of their GGF initiative and instead switch available funds to more important priorities such as sustaining, growing and modernizing the existing fleet. Even though state-of-art USN vessels such as ‘all-electric’ Destroyers could feasibly operate on ‘biogas’ (somewhat consistent with part of the current GGF initiative), the USN needs to fully evaluate the costs, alternatives and true benefits of all ‘green energy’ options. For example, operating a state-of-art all-electric Destroyer on biogas will most likely require building and towing a biogas tanker barge; due to the fact that the biogas energy density is but a fraction of the petroleum marine diesel that theoretically could be displaced. The performance and practicality of using biogas for potential combat operations would be a very poor decision compared to existing petroleum marine fuels usage.

If current and future government administrations are truly serious about reducing future U.S. carbon emissions they need to focus on the most cost effective alternatives to petroleum fossil fuels. Historically, the U.S. has been most successful in reducing its transportation sector’s petroleum consumption thru a combination of vehicle efficiency standards (CAFE) and ‘on-road’ biofuels (RFS). While building more efficient military vessels is and should be an ongoing USN priority, producing and consuming marine biofuels is an ineffective and extremely costly green energy initiative/action. If the Administration is truly serious about significantly reducing U.S. petroleum fuels consumption, a much more effective alternative would be to more aggressively produce and increase the level of U.S. transportation ‘on-road’ biofuels requirements; i.e. more significantly increase future annual RFS2 required biodiesel blending levels.

The advantages of further expanding the RFS2 regulation vs. a smaller-very inefficient GGF program are: 1) proven fairly cost-effective production performance (with positive full-lifecycle NEV’s and 50% carbon emission reductions), 2) extensive and existing biofuel transport and blending infrastructures (U.S.-wide supply chains that could be very cost-effectively expanded), and 3) on-road fuels consumption makes up the vast majority of the U.S. transportation sector’s petroleum consumption (the USN accounts for only 1% of total U.S. transportation sector petroleum consumption and about 2% of total distillate (diesel+jet) fuels consumption). Due to these existing commercial-scale advantages, more aggressively expanding existing on-road RFS2 standards should be far more cost and climate change effective than most any GGF advanced biofuel program-policy.

Who knows, someday building and operating increased numbers of nuclear power USN warships may become a feasible and cost effective GGF reality. In the meantime, utilizing advanced biofuels to significantly reduce U.S. transportation sector petroleum consumption and associated carbon emissions should be directed towards land-based/on-road vehicles only; and not the USN GGF. Your thoughts?

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Jeffery Surratt's picture
Jeffery Surratt on Jul 1, 2016

I spent 20 years on active duty, USAF 1975 to 1995 and the problem with many things DoD pursues is that cost is never a factor, it is not their money. But boy do they feel good about the programs they implement. Even if they know it is a waste of tax dollars once it gets going it has a life of its own.

Engineer- Poet's picture
Engineer- Poet on Jul 1, 2016

One of the things the Navy has been playing with lately is fuel-from-seawater.  Electrolysis both separates water into hydrogen and oxygen and also acidifies one stream to convert dissolved carbonate and bicarbonate to molecular CO2; hydrogen and CO2 can be converted to gasoline and diesel-range hydrocarbons by a variety of routes.

A nuclear Navy in which its nuclear ships generate fuel for the smaller vessels and aircraft would be relieved of one major supply constraint.  It could run at high speed for long distances with no extra constraints on its time on station.  Will we do it? I’m doubtful.

Jim Baird's picture
Jim Baird on Jul 2, 2016

John my thoughts were encapsulated here here and here .

Essentially I think the Navy could be producing the fuel it needs from its own environment through OTEC. I am no longer sold on the counter-current heat flow system but you get a similar benefit by using CO2 as the working fluid where the pressure internal pressure of the system works to counteract the external pressures working on the pipes.

By producing hydrogen through electrolysis at a pressure of 1000 meters the gas comes to the surface at about 70 percent of the pressure needed for transportation applications but it can be converted then to NH3 or hydrocarbons as EP suggests. I really don’t see why though the Navy can’t take a page out of the book of the likes of Toyota, Hyundai, etc when it to comes to fuel cells.

It would be a boon for the Navy as well as mankind if they would do it.

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