how are you working out your c.o.p. figures, am runnung my sg at 11.5v off single battery.using normal bedini battery charging twin battery circuit, collecter runs thru bridge and the battery also runs 60w dc flouro iight.so it seems to be 11.5v x 200ma to run systemand 50vx150 ma out, plus 60w. this should be2.3 watts to run and 67.5 out.this is not exact due to loosing .05v after 4-5 hour session,what figures should i be aiming for, any help