Have seen lots of buzz around supercapacitors from
IDTechEx.
Have mentioned them before in blog.
Beginning of 2014 saw news of new work on graphene devices.
Graphene solar cells.
Graphene supercapacitors.
How about combining the two? The core idea is to store the charge right where it is being generated, and cut down on transmission inefficiency while making the cells "flywheel" through darkness. And at the same time cut back (to zero) on all the voltage and amperage regulation needed for current (no pun intended) systems. Photovoltaic cell voltages are well matched to ultra-capacitor ratings.
If the graphene hybrid is too forward thinking, then go simply with standard commodity (cheapest) solar cell (say a nice 3-6W wafer or two - each 0.6V at 4-8A) and a big 5kF supercap. Now admittedly: The capacitor is big. It is heavy. It is only holding around an Ahr (integrating voltage). Alone, it is not for mobile applications. The /charging/ time constant is reasonable. Discharge depends on load and leakage.
However, the supercapacitor has an excellent temperature profile (can stand heat under a solar cell and cold in artic conditions), and excellent power density (can delivery a big power surge to a starting motor or...). The supercapacitor also offers an excellent front end for a battery hybrid. And the batteries can get you the next two orders of magnitude of raw storage... if they can be in a cooler place behind the refuge/buffer of the supercapacitor.
From there, there are other opportunities... Consider the atto or femto grid... Deliver solar photovoltaic energy - continuously - day and night - to directly attached fans and cooling units (eventually efficient solid state
Peltier?). Maybe use the first coolers to keep battery array temperatures stable? Keep the high current distances down to under a metre.
