diff --git a/config/default.cfg b/config/default.cfg
index 0c5a116f62de9f9a77f68d8717959f3ae6e44896..f752ae88e4f1d9cd0b4033f17b8ab0973c7653b5 100755
--- a/config/default.cfg
+++ b/config/default.cfg
@@ -157,7 +157,7 @@ cfg$gms$stationary  <- "off"      # def = off
 # ***---------------------    39_CCU    ---------------------------------
 # * (on): simple representation of carbon capture and utilization technologies, first only example of syngas (H22CH4)
 # * (off): no representation of carbon caputre and utilization technologies.
-cfg$gms$CCU  <- "off"      # def = off
+cfg$gms$CCU  <- "on"      # def = off
 
 # ***---------------------    40_techpol  ----------------------------------------
 # * (none): no technology policies
diff --git a/modules/39_CCU/on/bounds.gms b/modules/39_CCU/on/bounds.gms
index 3f6fd6e489d81c570c5fc7591c253a13194eda4b..b1748a44d3e834c44b89db200c4c3b5aa2ee6726 100644
--- a/modules/39_CCU/on/bounds.gms
+++ b/modules/39_CCU/on/bounds.gms
@@ -46,4 +46,9 @@ vm_co2capture.up(t,regi,"cco2","ico2","ccsinje","1") = 50;
 *** vm_prodSe.lo("2060","SSA",enty,"segafos",te) = 1;
 *** vm_prodSe.lo("2060","USA",enty,"segafos",te) = 0.5;
 
+vm_shSynSe.lo(t,regi)$(t.val > 2020) = 0.1;
+vm_shSynSe.lo(t,regi)$(t.val > 2025) = 0.2;
+vm_shSynSe.lo(t,regi)$(t.val > 2030) = 0.4;
+
+
 *** EOF ./modules/39_CCU/39_CCU.gms
diff --git a/modules/39_CCU/on/declarations.gms b/modules/39_CCU/on/declarations.gms
index bdf2fd85608c28f0221141be49d84ff8c8cfbf4a..0f0f09431d04b60fdfe5aed51036a2855721df22 100644
--- a/modules/39_CCU/on/declarations.gms
+++ b/modules/39_CCU/on/declarations.gms
@@ -25,6 +25,8 @@ p39_ratioCtoH(tall,all_regi,all_enty,all_enty,all_te,all_enty)         "ratio be
 
 positive variables
 vm_co2CCUshort(ttot,all_regi,all_enty,all_enty,all_te,rlf)           "CO2 captured in CCU te that have a persistence for co2 storage shorter than 5 years. Unit GtC/a"
+
+vm_shSynSe(ttot,all_regi)          "Share of synthetic liquids in all fossil liquids. Value between 0 and 1."
 ;
 
 
@@ -36,6 +38,8 @@ vm_co2CCUshort(ttot,all_regi,all_enty,all_enty,all_te,rlf)           "CO2 captur
 
 equations
 q39_emiCCU(ttot,all_regi)                                               "Managing the C/H ratio in CCU-Technologies"
+
+q39_shSynSe(ttot,all_regi)                    "Define share of synthetic liquids in all fossil liquids."
 ;
 
 *** EOF ./modules/39_CCU/on/declarations.gms
diff --git a/modules/39_CCU/on/equations.gms b/modules/39_CCU/on/equations.gms
index b0e053592076096d6ab5166806d2bf6739d2fc2e..0b9b2d3be627f9abcac6b498c5c5100385fd12fe 100644
--- a/modules/39_CCU/on/equations.gms
+++ b/modules/39_CCU/on/equations.gms
@@ -23,5 +23,13 @@ q39_emiCCU(t,regi) ..
   )
 ;
 
+q39_shSynSe(t,regi)..
+  (
+      sum(se2se(entySe,"seliqfos",te), vm_prodSe(t,regi,entySe,"seliqfos",te) ) +
+      sum(pe2se(entyPe,"seliqfos",te), vm_prodSe(t,regi,entyPe,"seliqfos",te) )
+  ) * vm_shSynSe(t,regi)
+  =e=
+  vm_prodSe(t,regi,"seh2","seliqfos","MeOH")
+;
 
 *** EOF ./modules/39_CCU/on/equations.gms