We discuss a new method to extract neutrino signals in low-energy experimen
ts. In this scheme the symmetric nature of most backgrounds allows for dire
ct cancellation from data. The application of this technique to the Pale Ve
rde reactor neutrino oscillation experiment allows us to reduce the measure
ment errors on the antineutrino flux from similar to 20% to similar to 10%.
We expect this method to substantially improve the data quality in future
low background experiments such as KamLAND and LENS.