diff --git a/src/main.c b/src/main.c
index fb34d16..a3b4e24 100644
--- a/src/main.c
+++ b/src/main.c
@@ -373,9 +373,12 @@ struct MPPState {
 
 	fxp_t maxPower;
 	int32_t maxPWM;
+
+	fxp_t powerAccu;
+	int32_t powerSamples;
 };
 
-#define MPP_TEST_DURATION 25 /* ms */
+#define MPP_TEST_DURATION 10 /* ms */
 
 #define MPP_TEST_STEPS 4
 const int32_t mpp_pwm_offsets[MPP_TEST_STEPS] = {-51, -4, 5, 50};
@@ -397,12 +400,24 @@ static void mpp_run(
 		mpp_state->maxPower = 0;
 		mpp_state->maxPWM = *pwm;
 
+		mpp_state->powerAccu = 0;
+		mpp_state->powerSamples = 0;
+
 		*pwm = *pwm + mpp_pwm_offsets[0];
 	} else if(mpp_state->testIdx < MPP_TEST_STEPS) {
 		/* test running */
+
+		/* accumulation */
+		mpp_state->powerAccu = fxp_add(mpp_state->powerAccu,
+				fxp_mult(power_state->vout, power_state->current));
+		mpp_state->powerSamples++;
+
 		if(time_in_state > mpp_state->nextTestStepTime) {
-			if(power_state->power_avg > mpp_state->maxPower) {
-				mpp_state->maxPower = power_state->power_avg;
+			/* averaging */
+			mpp_state->powerAccu = fxp_div(mpp_state->powerAccu, fxp_from_int(mpp_state->powerSamples));
+
+			if(mpp_state->powerAccu > mpp_state->maxPower) {
+				mpp_state->maxPower = mpp_state->powerAccu;
 				mpp_state->maxPWM = *pwm;
 			}
 
@@ -412,6 +427,10 @@ static void mpp_run(
 				*pwm = mpp_state->refPWM + mpp_pwm_offsets[mpp_state->testIdx];
 
 				mpp_state->nextTestStepTime = time_in_state + MPP_TEST_DURATION;
+
+				mpp_state->powerAccu = 0;
+				mpp_state->powerSamples = 0;
+
 			}
 		}