"savings of up to 16 per cent"
I could be mistaken since I haven't had time to really read through in depth, but from a skim it would appear that this 16 percent doesn't take into account the cost of the storage itself, meaning this is purely in the realm of theoretical rather than practical.
BTW... it's "percent" not "per cent" or else you'd have to identify 16 of what per cent, such as 16 one hundredth cents per cent.
P. James: Thanks for pointing out "percent" word break. And yes, it is purely a research project and the link to the paper at end of story describes what is possible: http://eprints.ecs.soton.ac.uk/22262/1/voice_etal_aaai2011.pdf