diff --git a/src/mqtt.js b/src/mqtt.js
index 8897cae..dbd20c5 100644
--- a/src/mqtt.js
+++ b/src/mqtt.js
@@ -88,6 +88,11 @@ const optionsList = [
         type: Number,
         description: "Environment Metrics older than this many seconds will be purged from the database.",
     },
+    {
+        name: "purge-power-metrics-after-seconds",
+        type: Number,
+        description: "Power Metrics older than this many seconds will be purged from the database.",
+    },
     {
         name: "purge-nodes-unheard-for-seconds",
         type: Number,
@@ -137,6 +142,7 @@ const purgeIntervalSeconds = options["purge-interval-seconds"] ?? 10;
 const purgeNodesUnheardForSeconds = options["purge-nodes-unheard-for-seconds"] ?? null;
 const purgeDeviceMetricsAfterSeconds = options["purge-device-metrics-after-seconds"] ?? null;
 const purgeEnvironmentMetricsAfterSeconds = options["purge-environment-metrics-after-seconds"] ?? null;
+const purgePowerMetricsAfterSeconds = options["purge-power-metrics-after-seconds"] ?? null;
 const purgePositionsAfterSeconds = options["purge-positions-after-seconds"] ?? null;
 
 // create mqtt client
@@ -165,6 +171,7 @@ if(purgeIntervalSeconds){
         await purgeUnheardNodes();
         await purgeOldDeviceMetrics();
         await purgeOldEnvironmentMetrics();
+        await purgeOldPowerMetrics();
         await purgeOldPositions();
     }, purgeIntervalSeconds * 1000);
 }
@@ -247,6 +254,32 @@ async function purgeOldEnvironmentMetrics() {
 
 }
 
+/**
+ * Purges all power metrics from the database that are older than the configured timeframe.
+ */
+async function purgeOldPowerMetrics() {
+
+    // make sure seconds provided
+    if(!purgePowerMetricsAfterSeconds){
+        return;
+    }
+
+    // delete all power metrics that are older than the configured purge time
+    try {
+        await prisma.powerMetric.deleteMany({
+            where: {
+                created_at: {
+                    // last updated before x seconds ago
+                    lt: new Date(Date.now() - purgePowerMetricsAfterSeconds * 1000),
+                },
+            }
+        });
+    } catch(e) {
+        // do nothing
+    }
+
+}
+
 /**
  * Purges all positions from the database that are older than the configured timeframe.
  */