[0kto]

Since nuclear reactors emit neutrinos as well, there are experiments measuring the neutrino output at two different locations from a commercial power plant and compare the flux of neutrinos taking the mixing into account (as well as all the other sources, of course). Actually, I did an internship after school with one of the groups: https://www.mpi-hd.mpg.de/lin/research_dc.en.html