I would say the hazards of this device sure beat the hazards of kerosene lamps (fire, mostly). [1] lists a series of accidents with kerosene lamps in a three year period in a small town. I think a horse kicking over a kerosene lantern started one of the big Chicago fires. There's even a possibility that a kerosene lamp caused a deadly fire in modern USA [2]. And I'm guessing that fire would be a serious problem in small, dense areas such as the slums (not intended pejoratively) in the third world nations that are likely to have the most use for this.

Solar plus battery might be better than this, but this looks like a whole lot better than a kerosene lamp.

[1] http://www.thelampworks.com/lw_lamp_accidents.htm

[2] http://www.chicoer.com/20120322/kerosene-lamp-may-have-cause...