diff --git a/CHANGELOG.md b/CHANGELOG.md
index ce6e71377f..a7819c5e72 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -58,6 +58,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Refactor `WeatherSource` and `WeatherSourceWrapper` [#180](https://github.com/ie3-institute/simona/issues/180)
 - Remove unnecessary dependency `pekko-connectors-csv` [#857](https://github.com/ie3-institute/simona/issues/857)
 - Rewrote RefSystemTest from groovy to scala [#646](https://github.com/ie3-institute/simona/issues/646)
+- Rewrote FixedFeedModelTest from groovy to scala [#646](https://github.com/ie3-institute/simona/issues/646)
 
 ### Fixed
 - Removed a repeated line in the documentation of vn_simona config [#658](https://github.com/ie3-institute/simona/issues/658)
diff --git a/src/main/scala/edu/ie3/simona/model/participant/FixedFeedInModel.scala b/src/main/scala/edu/ie3/simona/model/participant/FixedFeedInModel.scala
index c50b2f6211..dbda236e4c 100644
--- a/src/main/scala/edu/ie3/simona/model/participant/FixedFeedInModel.scala
+++ b/src/main/scala/edu/ie3/simona/model/participant/FixedFeedInModel.scala
@@ -68,7 +68,7 @@ final case class FixedFeedInModel(
     * @return
     *   Active power
     */
-  override protected def calculateActivePower(
+  override def calculateActivePower(
       modelState: ConstantState.type,
       data: FixedRelevantData.type = FixedRelevantData,
   ): Power =
diff --git a/src/test/groovy/edu/ie3/simona/model/participant/FixedFeedModelTest.groovy b/src/test/groovy/edu/ie3/simona/model/participant/FixedFeedModelTest.groovy
deleted file mode 100644
index 268323d95f..0000000000
--- a/src/test/groovy/edu/ie3/simona/model/participant/FixedFeedModelTest.groovy
+++ /dev/null
@@ -1,79 +0,0 @@
-/*
- * © 2020. TU Dortmund University,
- * Institute of Energy Systems, Energy Efficiency and Energy Economics,
- * Research group Distribution grid planning and operation
- */
-
-package edu.ie3.simona.model.participant
-
-import static edu.ie3.util.quantities.PowerSystemUnits.*
-
-import edu.ie3.datamodel.models.OperationTime
-import edu.ie3.datamodel.models.input.NodeInput
-import edu.ie3.datamodel.models.input.OperatorInput
-import edu.ie3.datamodel.models.input.system.FixedFeedInInput
-import edu.ie3.datamodel.models.input.system.characteristic.CosPhiFixed
-import edu.ie3.datamodel.models.voltagelevels.GermanVoltageLevelUtils
-import edu.ie3.simona.model.SystemComponent
-import edu.ie3.simona.model.participant.control.QControl
-import edu.ie3.util.TimeUtil
-import edu.ie3.util.scala.quantities.Sq
-import spock.lang.Specification
-import squants.energy.*
-import tech.units.indriya.quantity.Quantities
-
-class FixedFeedModelTest extends Specification {
-
-  def fixedFeedInput = new FixedFeedInInput(
-  UUID.fromString("4eeaf76a-ec17-4fc3-872d-34b7d6004b03"),
-  "testFixedFeed",
-  OperatorInput.NO_OPERATOR_ASSIGNED,
-  OperationTime.notLimited(),
-  new NodeInput(
-  UUID.fromString("e5c1cde5-c161-4a4f-997f-fcf31fecbf57"),
-  "TestNodeInputModel",
-  OperatorInput.NO_OPERATOR_ASSIGNED,
-  OperationTime.notLimited(),
-  Quantities.getQuantity(1d, PU),
-  false,
-  NodeInput.DEFAULT_GEO_POSITION,
-  GermanVoltageLevelUtils.LV,
-  -1
-  ),
-  new CosPhiFixed("cosPhiFixed:{(0.0,0.95)}"),
-  null,
-  Quantities.getQuantity(282.74d, VOLTAMPERE),
-  0.95
-  )
-  def simulationStartDate = TimeUtil.withDefaults.toZonedDateTime("2020-01-01T00:00:00Z")
-  def simulationEndDate = TimeUtil.withDefaults.toZonedDateTime("2020-12-31T23:59:00Z")
-  def foreSeenOperationInterval =
-  SystemComponent.determineOperationInterval(
-  simulationStartDate,
-  simulationEndDate,
-  fixedFeedInput.operationTime
-  )
-
-  def expectedPower = Sq.create(fixedFeedInput.sRated.value.doubleValue() * -1 * fixedFeedInput.cosPhiRated * 1.0, Kilowatts$.MODULE$)
-
-  def "A fixed feed model should return approximately correct power calculations"() {
-    when:
-    def actualModel = new FixedFeedInModel(
-        fixedFeedInput.uuid,
-        fixedFeedInput.id,
-        foreSeenOperationInterval,
-        QControl.apply(fixedFeedInput.qCharacteristics),
-        Sq.create(
-        fixedFeedInput.sRated
-        .to(KILOWATT)
-        .value.doubleValue()
-        .doubleValue(),
-        Kilowatts$.MODULE$
-        ),
-        fixedFeedInput.cosPhiRated
-        )
-
-    then:
-    actualModel.calculateActivePower(ModelState.ConstantState$.MODULE$, CalcRelevantData.FixedRelevantData$.MODULE$) =~ expectedPower
-  }
-}
diff --git a/src/test/scala/edu/ie3/simona/model/participant/FixedFeedModelSpec.scala b/src/test/scala/edu/ie3/simona/model/participant/FixedFeedModelSpec.scala
new file mode 100644
index 0000000000..1de88e0918
--- /dev/null
+++ b/src/test/scala/edu/ie3/simona/model/participant/FixedFeedModelSpec.scala
@@ -0,0 +1,57 @@
+/*
+ * © 2024. TU Dortmund University,
+ * Institute of Energy Systems, Energy Efficiency and Energy Economics,
+ * Research group Distribution grid planning and operation
+ */
+
+package edu.ie3.simona.model.participant
+
+import edu.ie3.simona.model.participant.control.QControl
+import edu.ie3.simona.test.common.UnitSpec
+import edu.ie3.simona.test.common.input.FixedFeedInputTestData
+import edu.ie3.util.quantities.PowerSystemUnits
+import edu.ie3.util.scala.quantities.Sq
+import org.scalatest.prop.TableDrivenPropertyChecks
+import squants.energy.{Kilowatts, Power, Watts}
+
+class FixedFeedModelSpec
+    extends UnitSpec
+    with FixedFeedInputTestData
+    with TableDrivenPropertyChecks {
+  implicit val tolerance: Power = Watts(1d)
+  "Having a fixed feed model" when {
+
+    "The fixed feed model" should {
+      "return approximately correct power calculations" in {
+        val expectedPower = Kilowatts(
+          fixedFeedInput
+            .getsRated()
+            .to(PowerSystemUnits.KILOWATT)
+            .getValue
+            .doubleValue() * -1 * fixedFeedInput.getCosPhiRated
+        )
+
+        val actualModel = new FixedFeedInModel(
+          fixedFeedInput.getUuid,
+          fixedFeedInput.getId,
+          defaultOperationInterval,
+          QControl.apply(fixedFeedInput.getqCharacteristics()),
+          Kilowatts(
+            fixedFeedInput
+              .getsRated()
+              .to(PowerSystemUnits.KILOWATT)
+              .getValue
+              .doubleValue()
+          ),
+          fixedFeedInput.getCosPhiRated,
+        )
+
+        actualModel.calculateActivePower(
+          ModelState.ConstantState,
+          CalcRelevantData.FixedRelevantData,
+        ) =~ expectedPower
+      }
+    }
+
+  }
+}