A place that I found to be a real hotbed of product development and implementation is the military. Financial and strategic rationale is pretty simple. One report states that while the US Military could purchase one gallon of fuel for $1, it costs approximately $400 to make that gallon available for use in the field. Strategically, battles are won and lost over fuel and supply lines - the classic example being Rommel in Northern Africa. Additionally, a lot of the petroleum comes from areas where political landscapes and relationships can be volatile. Being dependent on long supply lines or supplies from uncertain areas could be a major vulnerability. In response to these concerns, the military is acting on a few fronts: develop alternate sources of fuel, increase efficiency of operations, and off-grid power centers.
Military Goals for Renewable Energy
Alternate sources of fuel (especially if homegrown) reduce dependence on sources that may be less sympathetic. The military aims to have 20% of its energy supply renewable by 2020 and 25% by 2025. While there are plenty of options for terrestrial vehicles or generators (ethanol, bio-diesel, green diesel, etc.), aviation fuel demand is a little more specific. Simply using ethanol or recycled fryer oil will not work. The US Air Force and Navy have each completed test flights with jet fuel blends partially refined from plant or algae origins - the Navy even broke the sound barrier.
Improving fuel efficiency of an operating military can target many different areas. First you might think of vehicles. The Navy has outfitted an amphibious assault with a hybrid fuel system projected to save $250 million over the life of the ship. But the bases where soldiers sleep and eat, where equipment is housed and maintained, and where supplies are kept also consume a large portion of the total energy demand - and will only increase as technology becomes further integrated. Energy saved in lighting, heating, cooling, powering equipment, or recharging the countless batteries used in a modern force not only reduces cost but shrinks supply lines logistics and increases mobility. Improvement can be focused on the devices and power systems themselves, but heating and cooling is energy intensive so and tents are getting a makeover.
Generating power 'off-grid' is a strong asset to any group that values versatility and mobility in remote areas. The current solution is large diesel generators. This is a reliable technology that is easy to use, though transporting heavy machinery and fuel can be difficult. Relying on diesel fuel can be a vulnerability logistically, strategically, and politically. Micro-grids could be one solution. At a minimum, this is a power generator serving a small area, whether isolated or integrated into a larger grid, to provide uninterrupted power. This type of system can easily find practical use in the US or anywhere else in the world with semi-remote to remote areas that might be difficult to connect to the main grid. Micro-grids can also be used to strengthen weak points in the main grid and improve distribution. The generator can be solar or wind for mobile applications. In the civilian world, a modular nuclear reactor can be a more permanent source for a mini-grid. Miniature examples of this can be seen on back country trails in the form of tiny solar cells (I own one, and they are handy if you like gadgets.) clipped to bags used to recharge iPods, cameras, cell phones, or other electronics.
The US military is a major consumer of energy and any initiative it takes can be a major market driver. The military has different economics since its fuel (as used in the field) comes with many extra costs, but it can provide a fertile testing ground for new technologies and their durability. This would not be the first time that the military (or other governmental agency) spurred innovation and technology in the private sector.