--- a/RELEASE_NOTES	Mon Jan 29 21:29:02 2018 -0600
+++ b/RELEASE_NOTES	Tue Oct 24 22:04:13 2017 +0200
@@ -38,6 +38,7 @@
 - Bug 2764 - wifi: WifiSpectrumModelId doesn't distinguish 11ax from legacy
 - Bug 2766 - core: Modify logging for int64x64 to avoid stack overflow
 - Bug 2768 - lte: LteUeNetDevice has a null MAC address
+- Bug 2807 - energy: GetTotalEnergyConsumption is not updated correctly
 - Bug 2820 - wifi: segmentation fault when Rrpaa wifi manager is used
 - Bug 2824 - ICMP opcode fr fragment timeout drop is wrong
 - Bug 2828 - OLSR simple P2P example produces wrong results

--- a/src/energy/model/simple-device-energy-model.cc	Mon Jan 29 21:29:02 2018 -0600
+++ b/src/energy/model/simple-device-energy-model.cc	Tue Oct 24 22:04:13 2017 +0200
@@ -85,7 +85,15 @@
 SimpleDeviceEnergyModel::GetTotalEnergyConsumption (void) const
 {
   NS_LOG_FUNCTION (this);
-  return m_totalEnergyConsumption;
+  Time duration = Simulator::Now () - m_lastUpdateTime;
+
+  double energyToDecrease = 0.0;
+  double supplyVoltage = m_source->GetSupplyVoltage ();
+  energyToDecrease = duration.GetSeconds () * m_actualCurrentA * supplyVoltage;
+
+  m_source->UpdateEnergySource ();
+
+  return m_totalEnergyConsumption + energyToDecrease;
 }
 
 void

--- a/src/wifi/model/wifi-radio-energy-model.cc	Mon Jan 29 21:29:02 2018 -0600
+++ b/src/wifi/model/wifi-radio-energy-model.cc	Tue Oct 24 22:04:13 2017 +0200
@@ -119,7 +119,41 @@
 WifiRadioEnergyModel::GetTotalEnergyConsumption (void) const
 {
   NS_LOG_FUNCTION (this);
-  return m_totalEnergyConsumption;
+
+  Time duration = Simulator::Now () - m_lastUpdateTime;
+  NS_ASSERT (duration.GetNanoSeconds () >= 0); // check if duration is valid
+
+  // energy to decrease = current * voltage * time
+  double energyToDecrease = 0.0;
+  double supplyVoltage = m_source->GetSupplyVoltage ();
+  switch (m_currentState)
+    {
+    case WifiPhy::IDLE:
+      energyToDecrease = duration.GetSeconds () * m_idleCurrentA * supplyVoltage;
+      break;
+    case WifiPhy::CCA_BUSY:
+      energyToDecrease = duration.GetSeconds () * m_ccaBusyCurrentA * supplyVoltage;
+      break;
+    case WifiPhy::TX:
+      energyToDecrease = duration.GetSeconds () * m_txCurrentA * supplyVoltage;
+      break;
+    case WifiPhy::RX:
+      energyToDecrease = duration.GetSeconds () * m_rxCurrentA * supplyVoltage;
+      break;
+    case WifiPhy::SWITCHING:
+      energyToDecrease = duration.GetSeconds () * m_switchingCurrentA * supplyVoltage;
+      break;
+    case WifiPhy::SLEEP:
+      energyToDecrease = duration.GetSeconds () * m_sleepCurrentA * supplyVoltage;
+      break;
+    default:
+      NS_FATAL_ERROR ("WifiRadioEnergyModel:Undefined radio state: " << m_currentState);
+    }
+
+  // notify energy source
+  m_source->UpdateEnergySource ();
+
+  return m_totalEnergyConsumption + energyToDecrease;
 }
 
 double