By roughly 2008, carbon microfilament capacitive storage devices were able to match the amount of energy stored perunit volume and perunitweight that chemical batteries were capable of.
The energy release from nuclear fission is roughly a million times greater perunitweight than fossil fuels, which is why nuclear fission is such a compelling long term energy source.
The authors cite one possibility for this slight increase in that those losing weight with lorcaserin were exposed to a somewhat greater dose perunit of body weight.