diff --git a/log.capnp b/log.capnp
index e01c8977e23607..46971d81a309e9 100644
--- a/log.capnp
+++ b/log.capnp
@@ -280,6 +280,7 @@ struct ThermalData {
   batteryVoltage @16 :Int32;
   usbOnline @12 :Bool;
   networkType @22 :NetworkType;
+  offroadPowerUsage @23 :UInt32;  # Power usage since going offroad in uWh
 
   fanSpeed @10 :UInt16;
   started @11 :Bool;