Tuesday's power failure in Washington has once again raised questions about the vulnerability of America’s electric power grid.

Fox News National Security Analyst KT McFarland spoke to experts Darren Hammell and Jonathan Pollet about potential threats.

The power grid “is very vulnerable, whether its physical attacks, mistakes like this one or even cyberattacks … there have been a lot of high visibility outages lately and there are just more we can expect,” said Hammell, chief strategy officer and co-founder of the energy management firm Princeton Power Systems.

Other notable incidents include last December’s power outage in Detroit caused by an aging underground cable failing. In 2011, a major transmission line went offline, causing outages in Arizona and Southern California.

“The problem is we’ve taken this old infrastructure and only upgraded the computer technology … but the actual assets are still old,” Pollet, founder of consulting firm Red Tiger Security, told FoxNews.com.

Through the Recovery Act, the Energy Department has so far invested roughly $4.5 billion to modernize and enhance the reliability of the nation's grid.

Without action, the current setup will allow for potential cyberattacks against the system.  

“We’ve taken an infrastructure that is older and we have this modernized equipment on top of it that is vulnerable to the same type of hacking attack that you see with [companies] like Target,” said Pollet.

He suggests applying a “robust and mature set of cyber-security controls to this critical infrastructure that before, was not connected to computer technology.”

Since 2010, the Energy Department has invested more than $100 million to develop grid infrastructure that can handle a cyberattack while sustaining critical functions.

The power grid being interconnected, while beneficial, can be pose challenges. There are more than 450,000 miles of high-voltage transmission lines that connect the grid across the country.

“Part of the solution is distributed generation – systems that generate power closer to where it’s used … there has to be a lot of investment in the grid … the question is where do we spend that money,” said Hammell.

Pollet predicts an uptick in spending for cyber security programs to protect the grid in the next few years. This will be focused on “perimeter protection, intrusion detection, and intrusion response … this will allow the [system] to be more robust from a cyber threat.”

Chris Snyder is a producer for FoxNews.com based in New York. Follow him on twitter: @ChrisSnyderFox