The report said increased access to renewable energy was driving planning not only at the Pentagon but at military establishments around the world.
The findings mean that military agencies in the United States and abroad will invest in new technologies as they embrace renewable sources of energy for peacetime uses and warfare, generating new business in energy and security industries.
Renewable energy is environmentally friendly and increasingly popular and a practical answer to issues arising from scarcity of conventional energy sources, especially in and around battle zones.
Renewable energy use can involve a range of media from solar and thermal power, wind to biofuels and synfuels to fuel cells. Each individual military organization may choose to opt for renewable sources most appropriate for its needs but growth in the area is certain over the next 20 years.
"Increased access to clean and reliable energy has become a leading priority for the U.S. Department of Defense and military agencies around the world," Pike Research said in the report.
Military agencies increasingly view renewable energy "both as a means of improving energy independence as well as for purposes of increasing the efficiency and performance of all aspects of operations across multiple domains, including base and facility operations, transport, and portable soldier power," said the report.
The various branches of the Pentagon combine to form the single largest consumer of energy in the world -- more than any other public or private entity and greater than more than 100 other nations, said the report.
"Energy consumption is the lifeblood of the U.S. military -- and the supporting governmental infrastructure that facilitates and controls it," said the report.
"As such, the myriad of military initiatives focused on fostering cleantech is anticipated to have a substantial impact on the development of the industry as a whole. This presents a sizable market opportunity for defense contractors, project developers and systems integrators, and technology developers across all renewable energy sectors."
Pike Research said global military agencies' spending on renewable energy technologies will continue to rise rapidly over the next two decades.
Expenditure will grow from $1.8 billion in 2010 to $26.8 billion by 2030, said the report. The majority of the spending will be for mobility applications, including portable soldier power as well as land, air and sea vehicles. Energy for running facilities will represent a significant portion of the market.
"Military investment in renewable energy and related technologies, in many cases, holds the potential to bridge the 'valley of death' that lies between research and development and full commercialization of these technologies," said Pike Research President Clint Wheelock.
"As such, the myriad of military initiatives focused on fostering cleantech is anticipated to have a substantial impact on the development of the industry as a whole. This presents a sizable market opportunity for defense contractors, project developers and systems integrators and technology developers across all renewable energy sectors," Wheelock said.
In the facilities domain, the market opportunity is largest for solar energy, followed by wind power and geothermal.
Military agencies are also utilizing microgrids for distributed energy generation that can be "islanded" from the commercial power grid and are ardent adopters of energy efficiency techniques.
In the mobility domain, much of the focus is on biofuels and synfuels that can serve as replacements for petrofuels for vehicles ranging from tactical vehicles, trucks and tanks to fighter jets and naval vessels. Portable soldier power is also a major priority, and the Pentagon in particular is pursuing a variety of fuel cells and advanced battery technologies in this area.
The Pike Research report followed criticism of the military's "battery addiction" in various online discussion forums that deal with military efficiency and battle-readiness.
The defensetech.com Web site said the U.S. Army since 2004 has been "trying to break their battery addiction through researching alternative energy technologies."
The military is inefficient with energy and wants alternative energy sources but it needs more funding, said National Defense Industrial Association Defense Watch writer Sandra I. Erwin.
Although most of the criticism cited U.S. examples, the energy use trends were shared by military establishments worldwide, analysts said.