By Geoff Fein
The Office of Naval Research (ONR) is developing systems to enable Marines to take advantage of the Sun’s energy to charge batteries, run radios, laptops and sensors, all using commercially available components, according to the Navy.
A two-pronged effort is looking to provide the Marines with 300 watts of continuous power as well as develop a way for personnel to determine which renewable energy technology would be best to run a particular system, Eric Shields, test engineer at Naval Surface Warfare Center (NSWC) Carderock, Md., told Defense Daily Monday.
The first effort is a photovoltaic system paired with batteries, he said. “So you can run [systems] during the night as well as the day. Sufficient power during the day to run your equipment and charge the batteries that you will be using at night.”
In 2008, the Marines in Iraq issued a requirement for an expeditionary renewable power system. Based on that requirement, the Navy began looking at commercial technologies.
“One of the requirements is that each piece has to weigh less than 80 pounds so that it is man transportable,” Shields said.
He added that the system is not something a Marine can put on his or her back and lug around, but something that can be taken off a Humvee, for example, and carried up a hill or a short distance to set up.
The Ground Renewable Expeditionary Energy System (GREENS) began in 2008 as a requirement from Marines in Iraq looking for an expeditionary renewable power system, according to the Navy.
Shields said it has been a rapidly moving program, going from nothing to a prototype system in a year’s time.
“If you were going to go a traditional S&T route and start with a single solar cell and build up from there, we are talking years of development. What this is, is looking at what the best commercial industry has to offer and trying to ruggedize that for military applications,” he said. “These are actually commercial panels. What we did was an evaluation of eight to 10 different commercial companies and we found that these panels that we are using are the most reliable, most efficient, lightest weight on the market. It is all commercial. None of it is specifically designed for this application.”
The photovoltaic system has 28 volts of DC and 120 volts of AC, Shields added.
“We’ve been told the Marine Corps uses a lot of AC equipment, so it’s prepared to handle most of the equipment. Obviously, the higher power stuff it wouldn’t be able to handle,” he said.
For example, Shields pointed out that the system wouldn’t be used to run an air conditioner. “But you would be running radios, laptops, [doing] battery charging, those sorts of things you might see in a remote location.”
Additionally, the technology could run any sensors and the Ground Based Operational Surveillance System (GBOSS), he added.
And GREENS ability to cut down on fuel use will provide another important benefit, Shields noted.
“A lot of emphasis is being put on reducing fuel usage in the field, and how important that is in terms of reducing fuel convoys,” Shields said. “It seems like a lot of trouble to go through to have a heavy big renewable system. But, in the end, we hope it will reduce the amount of fuel that is being used and reduce the number of convoys and therefore the risk to soldiers or Marines in the field.”
Shields acknowledged the Marine Corps is working on getting a lighter battery and electronics systems, as well as something that is more reliable and does better at higher temperatures.
“We did some testing out in California (during Empire Challenge 2009), and at temperatures around 120F we weren’t getting maximum energy out of the system we thought we should be,” he said. “That is one of the things we are going to work on in this coming year. “
In addition to the effort to develop a system capable of delivering 300 watts of continuous power, GREENS also includes a tool kit that enables Marines to determine the best renewable energy components for a mission.
“The second part [of the program] was to develop a physical and digital trailer of tested renewable energy systems, so the Marine Corps could then have a physical trailer of systems they could walk into and take components and put them together and ship overseas,” Shields said. The digital part of the trailer would be a piece of software which would key them in on which system would work best for a particular application.”
Shields said the idea fit in with the Marine Corps’ very rapid “get it to work” kind of mentality. “It was a way for them to create solutions for particular scenarios where renewable energy would play a good role.”
The Marines are using a similar software system now to match power needs with particular applications, Shields noted.
“For example, if they are going on a recon mission and they have X number of personnel for X days, there are pieces of software that will tell them how many batteries of each type they need to take,” he said. “This is a modification of that concept. It is somewhat unique in that sense.”
Since the testing earlier this year at Empire Challenge 2009, the Navy and Marine Corps have built 20 systems, Shields said.
“Once we found, based on [using] commercial components, that you could really make this work, and make it simple enough that a Marine [in theater] could use it, that’s when it got a little bit more support and why we decided to pursue building 20 systems,” he said.
Some of the work is being done at NSWC Carderock and some of it at Marine Corps system Command at Quantico, Va., Shields added.
While the focus has been on the GREENS program, Shields said personnel at NSWC Carderock are also looking at a similar effort for using wind power.
“This year we are planning on focusing on developing a sister system, to see whether it is possible or not to do a similar thing with wind power,” he said. “Whether or not it is practical for Marines to set that up in a rapidly deployed fashion. Hopefully, we will have the same success as we did with the solar system.”
It’s very early on in the wind power effort, Shields added. “We are doing basic online research.”
But he noted the program will be a lot like GREENS.
“Similar to what we did with the solar panel evaluation, we will do something similar with wind turbines,” Shields said. “We are looking for the best products the commercial market has to offer, so we will test anything we can find.”