Story highlights Railgun prototype fires missiles at 7.5 times the speed of sound

Laser weapon costs about $1 a shot

Lab says it can make fuel from seawater

High-tech destroyer to be christened Saturday

Imagine ships that fire missiles at seven times the speed of sound without using explosives, or that use lasers to destroy threats at the cost of about a dollar a shot, and vessels making fuel from the very seawater in which they're floating.

That's the glimpse of the high-tech future the U.S. Navy gave this week. And these aren't just ideas. They've all been shown to work to some degree.

Saturday, the Navy will christen its most advanced warship ever, the destroyer USS Zumwalt, which may one day be using these new technologies.

The Zumwalt, which was launched last year and is to be christened at Bath Iron Works in Maine, is the Navy's first stealth destroyer. At 610 feet long and 80 feet wide, it's about 100 feet longer and 20 feet wider than ships in the Navy's current fleet of Arleigh Burke class destroyers, but the canopy and the rest of the Zumwalt is built on angles that help make it 50 times harder to spot on radar than an ordinary destroyer.

"It has the radar cross-section of a fishing boat," Chris Johnson, a spokesman for Naval Sea Systems Command, told CNN when the ship was launched last year.

In its current configuration, the Zumwalt will carry a considerable arsenal of weapons, including two Advanced Gun Systems (AGS), which can fire rocket-powered, computer-guided shells that can destroy targets 63 miles away. That's three times farther than ordinary destroyer guns can fire.

But in the future, it could be fitted with the even more advanced systems the Navy talked about this week.

One, a laser weapon prototype, will be tested aboard the amphibious transport dock USS Ponce in the Persian Gulf this summer, the Navy said.

The Laser Weapon System (LaWS) will be tested at sea this summer.

"This is a revolutionary capability," Rear Adm. Matthew Klunder, chief of Naval Research, said in a statement. "This very affordable technology is going to change the way we fight and save lives."

The laser weapon is design to take on aircraft or small surface vessels that may pose threats to Navy ships. Tests in 2011 and 2012 showed it can accomplish that mission.

The laser can be fired by one sailor using a video game-like console and do it at little cost, the Navy said.

"Spending about $1 per shot of a directed-energy source that never runs out gives us an alternative to firing costly munitions at inexpensive threats," Klunder said.

The Navy thinks the other weapon prototype it discussed this week, the electromagnetic railgun, will save money while providing a more potent force.

The gun uses electromagnetic force to send a missile to a range of 125 miles at 7.5 times the speed of sound, according to the Navy. When it hits its target, the projectile does its damage with sheer speed. It does not have an explosive warhead.

The EM Railgun launches projectiles using electricity instead of chemical propellants.

"The electromagnetic railgun represents an incredible new offensive capability for the U.S. Navy," Rear Adm. Bryant Fuller, the Navy's chief engineer, said in a statement. "This capability will allow us to effectively counter a wide range of threats at a relatively low cost, while keeping our ships and sailors safer by removing the need to carry as many high-explosive weapons."

The Navy said the railgun will be tested at sea aboard the USS Millinocket, a non-combat ship known as a joint high-speed vessel, in 2016. No decision has been made on which combat ships might eventually be deployed with a railgun.

No matter what ships are chosen, other Navy scientists said this week those vessels may someday draw their fuel from the oceans they're crossing.

Researchers at the U.S. Naval Research Laboratory, Materials Science and Technology Division, said this week they have demonstrated proof-of-concept on the ability to draw carbon dioxide and hydrogen from seawater and turn it into forms of gasoline.

Heather Willauer, a Naval Research Laboratory chemist, called the technology "game changing."

"This is the first time technology of this nature has been demonstrated with the potential for transition, from the laboratory, to full-scale commercial implementation," she said in a statement.

The lab's researchers used "an innovative and proprietary NRL electrolytic cation exchange module" to remove the carbon dioxide from the water and produce hydrogen gas in the process.

"The gases are then converted to liquid hydrocarbons by a metal catalyst in a reactor system," the research lab's statement said.

The fuel produced was used to power the engine of a small model aircraft, the researchers said.

The process could be ramped up to produce a replacement for jet fuel at a cost of $3 to $6 per gallon within a decade, the researchers said. That step would come on land, with versions to be used on ships coming later, they said.

Writing on the Navy's official blog this week , Vice Adm. Phil Cullom, deputy chief of Naval Operations for Fleet Readiness and Logistics, also called the new technology "game changing" and potentially life saving.

"After more than a decade of war, our adversaries have found certain soft underbellies to our operations. They know that when you go after the logistics and resupply of fuel, that's an easier target than confronting our frontline forces. What if we removed that from the equation? Can you imagine a time when an aircraft carrier doesn't have to wait for the oiler to come steaming alongside it to deliver jet fuel? It truly does change things. It prevents what could one day be our 'maritime IED moment,'" Cullom wrote.