diff --git a/src/charge_control.c b/src/charge_control.c
index 3cd5ddb..e0c8a15 100644
--- a/src/charge_control.c
+++ b/src/charge_control.c
@@ -289,9 +289,6 @@ void charge_control_update(uint64_t uptime_ms, struct MeasurementResult *meas)
 		discharge_state_entered_timestamp = uptime_ms;
 	}
 
-	/* calculate charge pump excess voltage above battery voltage. */
-	fxp_t charge_pump_voltage_delta = fxp_sub(meas->u_sw, meas->u_bat);
-
 	/* generalized charge pump control */
 	if(charge_state_entered || discharge_state_entered) {
 		if(charge_state == CHARGE_WAIT_CHARGEPUMP