It's a key problem for the energy industry: finding a way to store electricity to use when demand is at its highest or when none can be generated.
And energy storage is one of the United States Office of Electricity Delivery & Energy Reliability's top priorities. Any significant advance in this area would, according to its website, "represent a major breakthrough in electricity distribution… These devices can also help make renewable energy, whose power output cannot be controlled by grid operators, smooth and dispatchable."
Pittsburgh-based Aquion Energy believe they have developed a potentially game-changing energy storage device by using what the company describes as a 'twist' on saltwater batteries, a 200 year old technology according to Aquion.
Jay Whitacre is the founder and CTO of Aquion Energy. Before his role at Aquion, Whitacre worked on energy storage for NASA's Mars rover program.
As an Assistant Professor at Carnegie Mellon University, Whitacre was able to research and develop, "the chemistry that is the basis for Aquion Energy's product line," according to the company's website.
"It took me a while to make the full transition from… the small, niche kind of applications for spacecraft… to something that was for this planet, for the masses," Whitacre told CNBC's Sustainable Energy.
"When I came to Carnegie Mellon I decided to really examine the biggest possible problems that I could find, and this was one of them: stationary energy storage," he added.
Salt water was the key to developing and powering the batteries but what was missing was an environmentally friendly, low-cost, long-term technology.
"Using water seemed like a good idea, using sodium seemed like a good idea, and then finding the right materials that could function with the salt water… environment was a yearlong process," he added.
The battery developed by Aquion contains a base oxide, a synthetic cotton separator, a carbon composite anode and a sodium sulfate electrolyte.
The company describes its patented Aqueous Hybrid Ion technology as providing a, "high performance, safe, sustainable, and cost effective energy storage for long duration stationary applications."
For Whitacre, the work Aquion are doing is part of a bigger picture. "We have to find a way to grow energy availability around the world without further negatively impacting our environment: this means we have to use renewable energy sources," he said.