Yea in a capacitor the electrons (i.e. the electircal charge) is held only in the surface area between the two poles. More the poles overlap the more charge they can hold, Also the better the insulator between means that they can store higher voltage which again greatley increces the amout of charge it can store. nano tubes are very useful in both regards and indeed research envolving them has been ongoing for several years now, despite media and such proclaiming its all new.

Then again, as today technology is developed in a closed capitalistic world spending money to repeat others work is neccecary. But you never know, maybe they will find something they didnt the last time ^^

this doesn't make energy just stores it so yes it is more expensive, especially considering the fact it's a terrible idea.

When something thats new to energy field is written upon, it seems it is also way more expensive. How about taking million offered & start removing ineffiecent BAD system components. Like flooded electric tunnels, uninsulated wires thruout distribution grid, $100,000 copper transformers thrown out like old potatoes from mere small wire failing. Etc, its just too much to care, when Huge losses from Corporate providers won't even connect wires to transformer, getting paid to 100% waste fuel is BIG part of Energy.
Thomas Drashek

So spending money on supercapacitors, using nano tubes. US has had projects working on this for a couple of years now. Good to see us funding stuff where we already are playing catchup. 

Using nano tubes greatley increases the surface area that can store a charge. Since charge stored is all about available surface area (I think).

More expensive than a shiny new fission reactor and attendent spent fuel disposal system?