The invention concerns a method for the production of nitrate containing products from undercooling melts, wherein a XN\u2014water solution is evaporated up to a content of 50-99. In some embodiments, the comms apparatus does not need power and in other embodiments, its power may be harvested from the first electronic device, or drawn from a battery that may be recharged by harvesting means or charged directly. As an emission material on the filament is consumed and the vapor lamp reaches the end of its life, the resulting increase in voltage causes an arc.