To me, it's ridiculous that the major car companies (obviously, my bell weather example...but, conceptually applicable to other industries) haven't had hybrids on the market for decades.
I don't think hybrids are really the way forward, the Toyota is the one commonly mentioned, yet it's performance doesn't seem anything particularly special, and it's MPG isn't anything wonderful.
Really what is needed is a leap forward, no idea what or where, but playing at slightly improving existing technology isn't what is needed.
To steal from a well known science fiction author, what we need is 'Shipstones' - a small portable power storage device with exceptionally high capacity.