diff --git a/apps/openmw/mwmechanics/spellcasting.cpp b/apps/openmw/mwmechanics/spellcasting.cpp
index 6d6b9d950..70d097687 100644
--- a/apps/openmw/mwmechanics/spellcasting.cpp
+++ b/apps/openmw/mwmechanics/spellcasting.cpp
@@ -123,6 +123,9 @@ namespace MWMechanics
             }
         }
 
+        if (spell->mData.mType == ESM::Spell::ST_Power)
+            return stats.getSpells().canUsePower(spell->mId) ? 100 : 0;
+
         if (spell->mData.mType != ESM::Spell::ST_Spell)
             return 100;
 
@@ -817,6 +820,10 @@ namespace MWMechanics
                 sndMgr->playSound3D(mCaster, "Spell Failure " + schools[school], 1.0f, 1.0f);
                 return false;
             }
+
+            // A power can be used once per 24h
+            if (spell->mData.mType == ESM::Spell::ST_Power)
+                stats.getSpells().usePower(spell->mId);
         }
 
         if (mCaster == getPlayer() && spellIncreasesSkill(spell))
diff --git a/apps/openmw/mwmechanics/spells.cpp b/apps/openmw/mwmechanics/spells.cpp
index 6d7673a59..330d78a20 100644
--- a/apps/openmw/mwmechanics/spells.cpp
+++ b/apps/openmw/mwmechanics/spells.cpp
@@ -312,7 +312,7 @@ namespace MWMechanics
 
     bool Spells::canUsePower(const std::string &power) const
     {
-        std::map<std::string, MWWorld::TimeStamp>::const_iterator it = mUsedPowers.find(power);
+        std::map<std::string, MWWorld::TimeStamp>::const_iterator it = mUsedPowers.find(Misc::StringUtils::lowerCase(power));
         if (it == mUsedPowers.end() || it->second + 24 <= MWBase::Environment::get().getWorld()->getTimeStamp())
             return true;
         else
@@ -321,7 +321,7 @@ namespace MWMechanics
 
     void Spells::usePower(const std::string &power)
     {
-        mUsedPowers[power] = MWBase::Environment::get().getWorld()->getTimeStamp();
+        mUsedPowers[Misc::StringUtils::lowerCase(power)] = MWBase::Environment::get().getWorld()->getTimeStamp();
     }
 
     void Spells::readState(const ESM::SpellState &state)
diff --git a/apps/openmw/mwworld/worldimp.cpp b/apps/openmw/mwworld/worldimp.cpp
index 585786136..d994a35ee 100644
--- a/apps/openmw/mwworld/worldimp.cpp
+++ b/apps/openmw/mwworld/worldimp.cpp
@@ -2660,10 +2660,6 @@ namespace MWWorld
         {
             const ESM::Spell* spell = getStore().get<ESM::Spell>().find(selectedSpell);
 
-            // A power can be used once per 24h
-            if (spell->mData.mType == ESM::Spell::ST_Power)
-                stats.getSpells().usePower(spell->mId);
-
             cast.cast(spell);
         }
         else if (actor.getClass().hasInventoryStore(actor))