Monitor[Epot1 =
   Table[NIntegrate[
     fun1[[i]][x]^2 Vdc[x, distTab[[i]]], {x, -20, 20}], {i, 1,
     Length[fun1]}], i];
Monitor[Epot2 =
   Table[NIntegrate[
     fun2[[i]][x]^2 Vdc[x, distTab[[i]]], {x, -20, 20}], {i, 1,
     Length[fun1]}], i];
Show[{ListPlot[{distTab, Epot1}\[Transpose], PlotStyle -> Blue],
  ListPlot[{distTab, Epot2}\[Transpose], PlotStyle -> Red]},
 PlotRange -> All]