diff --git a/site_ansto/instrument/tas/config/motors/motor_configuration.tcl b/site_ansto/instrument/tas/config/motors/motor_configuration.tcl
index a6d62ea9..5d99a14f 100644
--- a/site_ansto/instrument/tas/config/motors/motor_configuration.tcl
+++ b/site_ansto/instrument/tas/config/motors/motor_configuration.tcl
@@ -836,4 +836,39 @@ make_gap_motors ss2vg gap ss2vo offset ps_top ps_bottom mm sample/vertical
 make_gap_motors ss2hg gap ss2ho offset ps_left ps_right mm sample/horizontal
 # END MOTOR CONFIGURATION
 
+# Virtual motor for Ei on Taipan
+#
+# Convert M2 angle to Energy in mEv
+proc get_vei {} {
+  set dd 3.35416e-10
+  set h_for_joules 6.62606957e-34
+  set neutron_mass 1.674927351e-27
+  set ev_to_joules 1.602176565e-19
+  set angle [expr 0.5 * [SplitReply [m2]]]
+  set wavelength [expr 2.0 * $dd * sin($angle * 3.141592654 / 180.0)]
+  set temp [expr ($h_for_joules / ($neutron_mass * $wavelength))]
+  set joules [expr 0.5 * $neutron_mass * ($temp * $temp)]
+  set mEv [expr 1000 * $joules / $ev_to_joules]
+  return $mEv
+}
+
+# Convert Energy in mEv to M1,M2 positions
+proc set_vei {mEv} {
+  set dd 3.35416e-10
+  set h_for_joules 6.62606957e-34
+  set neutron_mass 1.674927351e-27
+  set ev_to_joules 1.602176565e-19
+  set joules [expr 0.001 * $mEv * $ev_to_joules]
+  set wavelength [expr $h_for_joules / ($neutron_mass * sqrt(2.0 * $joules / $neutron_mass))]
+  set theta [expr (180.0 / 3.141592654) * asin($wavelength / (2.0 * $dd))]
+  set result [format "m1=%f,m2=%f" $theta [expr 2.0 * $theta]]
+  return $result
+}
+
+MakeConfigurableMotor vei
+vei readscript get_vei
+vei drivescript set_vei
+
+publish get_vei user
+publish set_vei user