diff --git a/wlauto/instrumentation/daq/__init__.py b/wlauto/instrumentation/daq/__init__.py
index 09976e34..33a7eb07 100644
--- a/wlauto/instrumentation/daq/__init__.py
+++ b/wlauto/instrumentation/daq/__init__.py
@@ -39,6 +39,7 @@ sys.path.pop(0)
 
 
 UNITS = {
+    'energy': 'Joules',
     'power': 'Watts',
     'voltage': 'Volts',
 }
@@ -165,6 +166,8 @@ class Daq(Instrument):
                     metric_name = '{}_{}'.format(port, metric)
                     context.result.add_metric(metric_name, round(value, 3), UNITS[metric])
                     self._results[key][metric_name] = round(value, 3)
+                energy = sum(data[metrics.index('power')]) * (self.sampling_rate / 1000000)
+                context.result.add_metric('{}_energy'.format(port), round(energy, 3), UNITS['energy'])
 
     def teardown(self, context):
         self.logger.debug('Terminating session.')