diff --git a/docs/src/manual/acOptimalPowerFlow.md b/docs/src/manual/acOptimalPowerFlow.md
index 74f02cad..df5a9872 100644
--- a/docs/src/manual/acOptimalPowerFlow.md
+++ b/docs/src/manual/acOptimalPowerFlow.md
@@ -39,11 +39,11 @@ addBranch!(system; label = "Branch 1", from = "Bus 1", to = "Bus 2", maxFromBus
 addGenerator!(system; label = "Generator 1", bus = "Bus 1", active = 0.4, reactive = 0.2)
 addGenerator!(system; label = "Generator 2", bus = "Bus 2", active = 0.2, reactive = 0.1)
 
-cost!(system; label = "Generator 1", active = 2, polynomial = [800.0; 200.0; 80.0])
-cost!(system; label = "Generator 2", active = 1, piecewise = [10.8 12.3; 14.7 16.8; 18 18.1])
+cost!(system; generator = "Generator 1", active = 2, polynomial = [800.0; 200.0; 80.0])
+cost!(system; generator = "Generator 2", active = 1, piecewise = [10.8 12.3; 14.7 16.8; 18 18.1])
 
-cost!(system; label = "Generator 1", reactive = 2, polynomial = [2.0])
-cost!(system; label = "Generator 2", reactive = 1, piecewise = [2.0 4.0; 6.0 8.0])
+cost!(system; generator = "Generator 1", reactive = 2, polynomial = [2.0])
+cost!(system; generator = "Generator 2", reactive = 1, piecewise = [2.0 4.0; 6.0 8.0])
 
 acModel!(system)
 nothing # hide
@@ -339,7 +339,7 @@ JuliaGrid also stores the objective function in a separate variable, which can b
 ##### Update Objective Function
 By utilizing the [`cost!`](@ref cost!) functions, users have the flexibility to modify the objective function by adjusting polynomial or linear piecewise coefficients or by changing the type of polynomial or linear piecewise function employed. For example, consider `Generator 1`, which employs a quadratic polynomial cost function for active power. We can redefine the cost function for this generator as a cubic polynomial and thereby define a nonlinear objective function:
 ```@example ACOptimalPowerFlow
-cost!(system, analysis; label = "Generator 1", active = 2, polynomial = [631; 257; 40; 5.0])
+cost!(system, analysis; generator = "Generator 1", active = 2, polynomial = [631; 257; 40; 5.0])
 nothing # hide
 ```
 
diff --git a/docs/src/manual/dcOptimalPowerFlow.md b/docs/src/manual/dcOptimalPowerFlow.md
index 199ba559..c78b62bf 100644
--- a/docs/src/manual/dcOptimalPowerFlow.md
+++ b/docs/src/manual/dcOptimalPowerFlow.md
@@ -38,9 +38,9 @@ addGenerator!(system; label = "Generator 1", bus = "Bus 1", active = 0.6, maxAct
 addGenerator!(system; label = "Generator 2", bus = "Bus 2", active = 0.1, maxActive = 0.3)
 addGenerator!(system; label = "Generator 3", bus = "Bus 2", active = 0.2, maxActive = 0.4)
 
-cost!(system; label = "Generator 1", active = 2, polynomial = [1100.2; 500; 80])
-cost!(system; label = "Generator 2", active = 1, piecewise = [8.0 11.0; 14.0 17.0])
-cost!(system; label = "Generator 3", active = 1, piecewise = [6.8 12.3; 8.7 16.8; 11.2 19.8])
+cost!(system; generator = "Generator 1", active = 2, polynomial = [1100.2; 500; 80])
+cost!(system; generator = "Generator 2", active = 1, piecewise = [8.0 11.0; 14.0 17.0])
+cost!(system; generator = "Generator 3", active = 1, piecewise = [6.8 12.3; 8.7 16.8; 11.2 19.8])
 
 dcModel!(system)
 nothing # hide
@@ -285,7 +285,7 @@ Additionally, JuliaGrid stores the objective function in a separate variable, al
 ##### Update Objective Function
 By utilizing the [`cost!`](@ref cost!) functions, users have the flexibility to modify the objective function by adjusting polynomial or linear piecewise cost coefficients or by changing the type of polynomial or linear piecewise function employed. For instance, consider `Generator 3`, which incorporates a piecewise cost structure with two segments. Now, we can define a polynomial function for this generator and activate it by specifying the keyword `active = 2` as shown:
 ```@example DCOptimalPowerFlow
-cost!(system, analysis; label = "Generator 3", active = 2, polynomial = [853.4; 257; 40])
+cost!(system, analysis; generator = "Generator 3", active = 2, polynomial = [853.4; 257; 40])
 ```
 
 This results in the updated objective function, which can be observed as follows:
diff --git a/docs/src/manual/powerSystemModel.md b/docs/src/manual/powerSystemModel.md
index d48e0cf6..6ac2d2fd 100644
--- a/docs/src/manual/powerSystemModel.md
+++ b/docs/src/manual/powerSystemModel.md
@@ -704,7 +704,7 @@ nothing # hide
 ##### Polynomial Cost
 Let us define a quadratic polynomial cost function for the active power produced by the `Generator 1`:
 ```@example addActiveCost
-cost!(system; label = "Generator 1", active = 2, polynomial = [1100.0; 500.0; 150.0])
+cost!(system; generator = "Generator 1", active = 2, polynomial = [1100.0; 500.0; 150.0])
 ```
 In essence, what we have accomplished is the establishment of a cost function depicted as ``f(P_{\text{g}1}) = 1100 P_{\text{g}1}^2 + 500 P_{\text{g}1} + 150`` through the code provided. In general, when constructing a polynomial cost function, the coefficients must be ordered from the highest degree to the lowest.
 
@@ -720,7 +720,7 @@ By setting `active = 2` within the function, we express our intent to specify th
 ##### Piecewise Linear Cost
 We can also create a piecewise linear cost function, for example, let us create the reactive power cost function for the same generator using the following code:
 ```@example addActiveCost
-cost!(system; label = "Generator 1", reactive = 1, piecewise = [0.11 12.3; 0.15 16.8])
+cost!(system; generator = "Generator 1", reactive = 1, piecewise = [0.11 12.3; 0.15 16.8])
 nothing # hide
 ```
 
@@ -740,7 +740,7 @@ nothing # hide
 
 Now, we can add the quadratic polynomial function using megawatts:
 ```@example addActiveCost
-cost!(system; label = "Generator 1", active = 2, polynomial = [0.11; 5.0; 150.0])
+cost!(system; generator = "Generator 1", active = 2, polynomial = [0.11; 5.0; 150.0])
 ```
 
 After inspecting the resulting cost data, we can see that it is the same as before:
@@ -750,7 +750,7 @@ system.generator.cost.active.polynomial[1]
 
 Similarly, we can define the linear piecewise cost using megavolt-amperes reactive:
 ```@example addActiveCost
-cost!(system; label = "Generator 1", reactive = 1, piecewise = [11.0 12.3; 15.0 16.8])
+cost!(system; generator = "Generator 1", reactive = 1, piecewise = [11.0 12.3; 15.0 16.8])
 nothing # hide
 ```
 
diff --git a/docs/src/tutorials/acOptimalPowerFlow.md b/docs/src/tutorials/acOptimalPowerFlow.md
index 7d256fca..983142ac 100644
--- a/docs/src/tutorials/acOptimalPowerFlow.md
+++ b/docs/src/tutorials/acOptimalPowerFlow.md
@@ -21,11 +21,11 @@ addBranch!(system; label = 1, from = 1, to = 2, maxFromBus = 0.15, maxToBus = 0.
 addGenerator!(system; label = 1, bus = 1, active = 0.4, reactive = 0.2)
 addGenerator!(system; label = 2, bus = 2, active = 0.2, reactive = 0.1)
 
-cost!(system; label = 1, active = 2, polynomial = [900.0; 500.0; 80.0; 5.0])
-cost!(system; label = 2, active = 1, piecewise =  [10.8 12.3; 14.7 16.8; 18 18.1])
+cost!(system; generator = 1, active = 2, polynomial = [900.0; 500.0; 80.0; 5.0])
+cost!(system; generator = 2, active = 1, piecewise =  [10.8 12.3; 14.7 16.8; 18 18.1])
 
-cost!(system; label = 1, reactive = 1, piecewise = [10.0 20.0; 20.0 40.0])
-cost!(system; label = 2, reactive = 2, polynomial = [2.0])
+cost!(system; generator = 1, reactive = 1, piecewise = [10.0 20.0; 20.0 40.0])
+cost!(system; generator = 2, reactive = 2, polynomial = [2.0])
 nothing # hide
 ```
 
diff --git a/docs/src/tutorials/dcOptimalPowerFlow.md b/docs/src/tutorials/dcOptimalPowerFlow.md
index 60b77507..c53fdf5d 100644
--- a/docs/src/tutorials/dcOptimalPowerFlow.md
+++ b/docs/src/tutorials/dcOptimalPowerFlow.md
@@ -23,8 +23,8 @@ addBranch!(system; label = 3, from = 2, to = 3, reactance = 0.01, maxFromBus = 0
 addGenerator!(system; label = 1, bus = 1, active = 3.2, maxActive = 0.5)
 addGenerator!(system; label = 2, bus = 2, active = 0.2, maxActive = 0.3)
 
-cost!(system; label = 1, active = 2, polynomial = [1100.2; 500; 80])
-cost!(system; label = 2, active = 1, piecewise =  [10.85 12.3; 14.77 16.8; 18 18.1])
+cost!(system; generator = 1, active = 2, polynomial = [1100.2; 500; 80])
+cost!(system; generator = 2, active = 1, piecewise =  [10.85 12.3; 14.77 16.8; 18 18.1])
 nothing # hide
 ```
 
diff --git a/src/backend/precompile.jl b/src/backend/precompile.jl
index 2276b63d..2ec820eb 100644
--- a/src/backend/precompile.jl
+++ b/src/backend/precompile.jl
@@ -9,7 +9,7 @@ PrecompileTools.@setup_workload begin
     addBus!(system; label = 2, type = 1, reactive = 0.05)
     addBranch!(system; from = 1, to = 2, reactance = 0.05)
     addGenerator!(system; bus = 1, active = 0.5, reactive = 0.1)
-    cost!(system; label = 1, active = 2, polynomial = [0.11; 5.0; 150.0])
+    cost!(system; generator = 1, active = 2, polynomial = [0.11; 5.0; 150.0])
 
     addPmu!(system, device; bus = 1, magnitude = 1.0, angle = 0.0)
     addPmu!(system, device; bus = 2, magnitude = 1.0, angle = 0.0)
diff --git a/src/powerSystem/generator.jl b/src/powerSystem/generator.jl
index 4469f3b8..be93c0de 100644
--- a/src/powerSystem/generator.jl
+++ b/src/powerSystem/generator.jl
@@ -733,7 +733,7 @@ macro generator(kwargs...)
 end
 
 """
-    cost!(system::PowerSystem, [analysis::Analysis]; label, active, reactive,
+    cost!(system::PowerSystem, [analysis::Analysis]; generator, active, reactive,
         piecewise, polynomial)
 
 The function either adds a new cost or modifies an existing one for the active or reactive
@@ -748,7 +748,7 @@ for completely reconstructing vectors and matrices when adding a new branch.
 
 # Keywords
 The function accepts five keywords:
-* `label`: Corresponds to the already defined generator label.
+* `generator`: Corresponds to the already defined generator label.
 * `active`: Active power cost model:
   * `active = 1`: adding or updating cost, and piecewise linear is being used,
   * `active = 2`: adding or updating cost, and polynomial is being used.
@@ -780,7 +780,7 @@ system = powerSystem()
 addBus!(system; label = "Bus 1", active = 0.25, reactive = -0.04, base = 132e3)
 
 addGenerator!(system; label = "Generator 1", bus = "Bus 1", active = 0.5)
-cost!(system; label = "Generator 1", active = 2, polynomial = [1100.0; 500.0; 150.0])
+cost!(system; generator = "Generator 1", active = 2, polynomial = [1100.0; 500.0; 150.0])
 ```
 
 Adding a cost using a custom unit system:
@@ -791,12 +791,12 @@ system = powerSystem()
 addBus!(system; label = "Bus 1", active = 25, reactive = -4, base = 132e3)
 
 addGenerator!(system; label = "Generator 1", bus = "Bus 1", active = 50, reactive = 10)
-cost!(system; label = "Generator 1", active = 2, polynomial = [0.11; 5.0; 150.0])
+cost!(system; generator = "Generator 1", active = 2, polynomial = [0.11; 5.0; 150.0])
 ```
 """
 function cost!(
     system::PowerSystem;
-    label::IntStrMiss,
+    generator::IntStrMiss,
     active::FltIntMiss = missing,
     reactive::FltIntMiss = missing,
     polynomial::Vector{Float64} = Float64[],
@@ -815,7 +815,7 @@ function cost!(
         )
     end
 
-    idx = system.generator.label[getLabel(system.generator, label, "generator")]
+    idx = system.generator.label[getLabel(system.generator, generator, "generator")]
 
     if isset(active)
         container = system.generator.cost.active
@@ -859,7 +859,7 @@ end
 function cost!(
     system::PowerSystem,
     analysis::ACOptimalPowerFlow;
-    label::IntStrMiss,
+    generator::IntStrMiss,
     active::FltIntMiss = missing,
     reactive::FltIntMiss = missing,
     polynomial::Vector{Float64} = Float64[],
@@ -872,14 +872,14 @@ function cost!(
     obj = analysis.method.objective
 
     dropZero = false
-    idx = gen.label[getLabel(gen, label, "generator")]
+    idx = gen.label[getLabel(gen, generator, "generator")]
 
     if gen.layout.status[idx] == 1
         actCost, isActwiseOld, isActNonlin = costExpr(
-            gen.cost.active, variable.active[idx], idx, label; ac = true
+            gen.cost.active, variable.active[idx], idx, generator; ac = true
         )
         reactCost, isReactwisOld, isReactNonlin = costExpr(
-            gen.cost.reactive, variable.reactive[idx], idx, label; ac = true
+            gen.cost.reactive, variable.reactive[idx], idx, generator; ac = true
         )
 
         @objective(jump, Min, 0.0)
@@ -905,14 +905,14 @@ function cost!(
         end
     end
 
-    cost!(system; label, active, reactive, polynomial, piecewise)
+    cost!(system; generator, active, reactive, polynomial, piecewise)
 
     if gen.layout.status[idx] == 1
         actCost, isActwiseNew, isActNonlin = costExpr(
-            gen.cost.active, variable.active[idx], idx, label; ac = true
+            gen.cost.active, variable.active[idx], idx, generator; ac = true
         )
         reactCost, isReactwiseNew, isReactNonlin = costExpr(
-            gen.cost.reactive, variable.reactive[idx], idx, label; ac = true
+            gen.cost.reactive, variable.reactive[idx], idx, generator; ac = true
         )
 
         if isActwiseNew
@@ -984,7 +984,7 @@ end
 function cost!(
     system::PowerSystem,
     analysis::DCOptimalPowerFlow;
-    label::IntStrMiss,
+    generator::IntStrMiss,
     active::FltIntMiss = missing,
     reactive::FltIntMiss = missing,
     polynomial::Vector{Float64} = Float64[],
@@ -996,10 +996,10 @@ function cost!(
     variable = analysis.method.variable
 
     dropZero = false
-    idx = gen.label[getLabel(gen, label, "generator")]
+    idx = gen.label[getLabel(gen, generator, "generator")]
 
     if gen.layout.status[idx] == 1
-        costOld, isPowerwiseOld = costExpr(gen.cost.active, variable.active[idx], idx, label)
+        costOld, isPowerwiseOld = costExpr(gen.cost.active, variable.active[idx], idx, generator)
 
         if isPowerwiseOld
             remove!(jump, constr.piecewise.active, idx)
@@ -1009,10 +1009,10 @@ function cost!(
         end
     end
 
-    cost!(system; label, active, reactive, polynomial, piecewise)
+    cost!(system; generator, active, reactive, polynomial, piecewise)
 
     if gen.layout.status[idx] == 1
-        costNew, isWiseNew = costExpr(gen.cost.active, variable.active[idx], idx, label)
+        costNew, isWiseNew = costExpr(gen.cost.active, variable.active[idx], idx, generator)
 
         if isWiseNew
             if !isPowerwiseOld
diff --git a/test/optimalPowerFlow/analysis.jl b/test/optimalPowerFlow/analysis.jl
index 6232791b..99f6fc37 100644
--- a/test/optimalPowerFlow/analysis.jl
+++ b/test/optimalPowerFlow/analysis.jl
@@ -291,7 +291,7 @@ end
     err = ErrorException("The slack bus is missing.")
     @test_throws err dcOptimalPowerFlow(system, Ipopt.Optimizer)
 
-    cost!(system; label = "Gen 1", active = 1, piecewise = [5.1 6.2])
+    cost!(system; generator = "Gen 1", active = 1, piecewise = [5.1 6.2])
     updateBus!(system; label = "Bus 1", type = 3)
     err = ErrorException(
         "The generator labeled Gen 1 has a piecewise linear cost " *
@@ -299,18 +299,18 @@ end
     )
     @test_throws err dcOptimalPowerFlow(system, Ipopt.Optimizer)
 
-    cost!(system; label = "Gen 1", active = 1, piecewise = [5.1 6.2; 4.1 5.2])
+    cost!(system; generator = "Gen 1", active = 1, piecewise = [5.1 6.2; 4.1 5.2])
     dc = dcOptimalPowerFlow(system, Ipopt.Optimizer)
     err = ErrorException(
         "The generator labeled Gen 1 has a piecewise linear cost " *
         "function with only one defined point."
     )
-    @test_throws err cost!(system, dc; label = "Gen 1", active = 1, piecewise = [5.1 6.2])
+    @test_throws err cost!(system, dc; generator = "Gen 1", active = 1, piecewise = [5.1 6.2])
 
     @capture_out print(dc.method.constraint.balance.active)
     @capture_out print(system.bus.label, dc.method.constraint.balance.active)
 
-    cost!(system; label = "Gen 1", active = 1, piecewise = [1.1 2.2; 2.1 3.2])
+    cost!(system; generator = "Gen 1", active = 1, piecewise = [1.1 2.2; 2.1 3.2])
     dc = dcOptimalPowerFlow(system, Ipopt.Optimizer)
     @capture_out print(system.generator.label, dc.method.constraint.piecewise.active)
     @capture_out print(dc.method.constraint.piecewise.active)
diff --git a/test/optimalPowerFlow/reusing.jl b/test/optimalPowerFlow/reusing.jl
index 6d679541..85ad6681 100644
--- a/test/optimalPowerFlow/reusing.jl
+++ b/test/optimalPowerFlow/reusing.jl
@@ -37,14 +37,14 @@
     updateGenerator!(system; label = 10, status = 0, maxActive = 0.8)
     updateGenerator!(system; label = 9, status = 0)
 
-    cost!(system; label = 10, active = 2, polynomial = [452.2; 31; 18; 5])
-    cost!(system; label = 9, active = 1, piecewise = [10.2 14.3; 11.5 16.1; 12.8 18.6])
-    cost!(system; label = 5, active = 1, piecewise = [10.2 14.3; 11.5 16.1; 12.8 18.6])
-    cost!(system; label = 5, active = 2, polynomial = [452.2; 31; 18; 5])
-    cost!(system; label = 5, active = 2, polynomial = [452.2; 31; 18])
-    cost!(system; label = 5, active = 2, polynomial = [452.2; 31; 18; 6])
-    cost!(system; label = 4, reactive = 2, polynomial = [452.2; 31; 18; 5])
-    cost!(system; label = 4, reactive = 1, piecewise = [10.2 14.3; 11.5 16.1; 12.8 18.6])
+    cost!(system; generator = 10, active = 2, polynomial = [452.2; 31; 18; 5])
+    cost!(system; generator = 9, active = 1, piecewise = [10.2 14.3; 11.5 16.1; 12.8 18.6])
+    cost!(system; generator = 5, active = 1, piecewise = [10.2 14.3; 11.5 16.1; 12.8 18.6])
+    cost!(system; generator = 5, active = 2, polynomial = [452.2; 31; 18; 5])
+    cost!(system; generator = 5, active = 2, polynomial = [452.2; 31; 18])
+    cost!(system; generator = 5, active = 2, polynomial = [452.2; 31; 18; 6])
+    cost!(system; generator = 4, reactive = 2, polynomial = [452.2; 31; 18; 5])
+    cost!(system; generator = 4, reactive = 1, piecewise = [10.2 14.3; 11.5 16.1; 12.8 18.6])
 
     acModel!(system)
     analysis = acOptimalPowerFlow(system, Ipopt.Optimizer)
@@ -86,7 +86,7 @@
     )
     cost!(
         resystem, reusing;
-        label = 9, active = 1, piecewise = [10.2 14.3; 11.5 16.1; 12.8 18.6]
+        generator = 9, active = 1, piecewise = [10.2 14.3; 11.5 16.1; 12.8 18.6]
     )
     addGenerator!(
         resystem, reusing;
@@ -100,17 +100,17 @@
 
     cost!(
         resystem, reusing;
-        label = 5, active = 1, piecewise = [10.2 14.3; 11.5 16.1; 12.8 18.6]
-    )
-    cost!(resystem, reusing; label = 10, active = 2, polynomial = [452.2; 31; 18; 5])
-    cost!(resystem, reusing; label = 5, active = 2, polynomial = [452.2; 31; 18; 5])
-    cost!(resystem, reusing; label = 5, active = 2, polynomial = [452.2; 31; 18])
-    cost!(resystem, reusing; label = 5, active = 2, polynomial = [452.2; 31; 18])
-    cost!(resystem, reusing; label = 5, active = 2, polynomial = [452.2; 31; 18; 6])
-    cost!(resystem, reusing; label = 4, reactive = 2, polynomial = [452.2; 31; 18; 5])
+        generator = 5, active = 1, piecewise = [10.2 14.3; 11.5 16.1; 12.8 18.6]
+    )
+    cost!(resystem, reusing; generator = 10, active = 2, polynomial = [452.2; 31; 18; 5])
+    cost!(resystem, reusing; generator = 5, active = 2, polynomial = [452.2; 31; 18; 5])
+    cost!(resystem, reusing; generator = 5, active = 2, polynomial = [452.2; 31; 18])
+    cost!(resystem, reusing; generator = 5, active = 2, polynomial = [452.2; 31; 18])
+    cost!(resystem, reusing; generator = 5, active = 2, polynomial = [452.2; 31; 18; 6])
+    cost!(resystem, reusing; generator = 4, reactive = 2, polynomial = [452.2; 31; 18; 5])
     cost!(
         resystem,
-        reusing; label = 4, reactive = 1, piecewise = [10.2 14.3; 11.5 16.1; 12.8 18.6]
+        reusing; generator = 4, reactive = 1, piecewise = [10.2 14.3; 11.5 16.1; 12.8 18.6]
     )
 
     set_silent(reusing.method.jump)
@@ -147,9 +147,9 @@
         system; label = 12, bus = 14, active = 0.3, minActive = 0.0, maxActive = 0.5
     )
 
-    cost!(system; label = 11, active = 2, polynomial = [165.0])
-    cost!(system; label = 10, active = 1, piecewise = [10.2 14.3; 11.5 16.1; 12.8 18.6])
-    cost!(system; label = 9, active = 2, polynomial = [856.2; 135.3; 80])
+    cost!(system; generator = 11, active = 2, polynomial = [165.0])
+    cost!(system; generator = 10, active = 1, piecewise = [10.2 14.3; 11.5 16.1; 12.8 18.6])
+    cost!(system; generator = 9, active = 2, polynomial = [856.2; 135.3; 80])
 
     acModel!(system)
     analysis = acOptimalPowerFlow(system, Ipopt.Optimizer)
@@ -181,10 +181,10 @@
 
     cost!(
         resystem, reusing;
-        label = 10, active = 1, piecewise = [10.2 14.3; 11.5 16.1; 12.8 18.6]
+        generator = 10, active = 1, piecewise = [10.2 14.3; 11.5 16.1; 12.8 18.6]
     )
-    cost!(resystem, reusing; label = 11, active = 2, polynomial = [165.0])
-    cost!(resystem, reusing; label = 9, active = 2, polynomial = [856.2; 135.3; 80])
+    cost!(resystem, reusing; generator = 11, active = 2, polynomial = [165.0])
+    cost!(resystem, reusing; generator = 9, active = 2, polynomial = [856.2; 135.3; 80])
 
     startingPrimal!(resystem, reusing)
     solve!(resystem, reusing)
@@ -230,13 +230,13 @@ end
         system;
         label = 9, bus = 3, active = 0.3, minActive = 0.0, maxActive = 0.5, status = 0
     )
-    cost!(system; label = 9, active = 1, piecewise = [10.2 14.3; 11.5 16.1; 12.8 18.6])
+    cost!(system; generator = 9, active = 1, piecewise = [10.2 14.3; 11.5 16.1; 12.8 18.6])
     addGenerator!(system; label = 10, bus = 3, active = 0.3)
-    cost!(system; label = 10, active = 1, piecewise = [10.2 14.3; 11.5 16.1])
+    cost!(system; generator = 10, active = 1, piecewise = [10.2 14.3; 11.5 16.1])
     updateGenerator!(system; label = 9, status = 1, maxActive = 0.8)
     updateGenerator!(system; label = 10, status = 0, maxActive = 0.8)
     updateGenerator!(system; label = 9, status = 0)
-    cost!(system; label = 5, active = 2, polynomial = [854.0, 116.0])
+    cost!(system; generator = 5, active = 2, polynomial = [854.0, 116.0])
 
     dcModel!(system)
     analysis = dcOptimalPowerFlow(system, Ipopt.Optimizer)
@@ -275,14 +275,14 @@ end
     )
     cost!(
         resystem, reusing;
-        label = 9, active = 1, piecewise = [10.2 14.3; 11.5 16.1; 12.8 18.6]
+        generator = 9, active = 1, piecewise = [10.2 14.3; 11.5 16.1; 12.8 18.6]
     )
     addGenerator!(resystem, reusing; label = 10, bus = 3, active = 0.3)
-    cost!(resystem, reusing; label = 10, active = 1, piecewise = [10.2 14.3; 11.5 16.1])
+    cost!(resystem, reusing; generator = 10, active = 1, piecewise = [10.2 14.3; 11.5 16.1])
     updateGenerator!(resystem, reusing; label = 9, status = 1, maxActive = 0.8)
     updateGenerator!(resystem, reusing; label = 10, status = 0, maxActive = 0.8)
     updateGenerator!(resystem, reusing; label = 9, status = 0)
-    cost!(resystem, reusing; label = 5, active = 2, polynomial = [854.0, 116.0])
+    cost!(resystem, reusing; generator = 5, active = 2, polynomial = [854.0, 116.0])
 
     set_silent(reusing.method.jump)
     solve!(resystem, reusing)
@@ -312,9 +312,9 @@ end
         system;
         label = 11, bus = 14, active = 0.3, minActive = 0.0, maxActive = 0.5, status = 0
     )
-    cost!(system; label = 11, active = 2, polynomial = [165.0])
-    cost!(system; label = 10, active = 1, piecewise = [10.2 14.3; 11.5 16.1; 12.8 18.6])
-    cost!(system; label = 9, active = 2, polynomial = [856.2; 135.3; 80])
+    cost!(system; generator = 11, active = 2, polynomial = [165.0])
+    cost!(system; generator = 10, active = 1, piecewise = [10.2 14.3; 11.5 16.1; 12.8 18.6])
+    cost!(system; generator = 9, active = 2, polynomial = [856.2; 135.3; 80])
 
     dcModel!(system)
     analysis = dcOptimalPowerFlow(system, Ipopt.Optimizer)
@@ -337,9 +337,9 @@ end
         resystem, reusing;
         label = 11, bus = 14, active = 0.3, minActive = 0.0, maxActive = 0.5, status = 0
     )
-    cost!(resystem, reusing; label = 11, active = 2, polynomial = [165.0])
-    cost!(resystem, reusing; label = 10, active = 1, piecewise = [10.2 14.3; 11.5 16.1; 12.8 18.6])
-    cost!(resystem, reusing; label = 9, active = 2, polynomial = [856.2; 135.3; 80])
+    cost!(resystem, reusing; generator = 11, active = 2, polynomial = [165.0])
+    cost!(resystem, reusing; generator = 10, active = 1, piecewise = [10.2 14.3; 11.5 16.1; 12.8 18.6])
+    cost!(resystem, reusing; generator = 9, active = 2, polynomial = [856.2; 135.3; 80])
 
     startingPrimal!(resystem, reusing)
     solve!(resystem, reusing)
diff --git a/test/powerSystem/buildUpdate.jl b/test/powerSystem/buildUpdate.jl
index e2d30ea1..edc9976b 100644
--- a/test/powerSystem/buildUpdate.jl
+++ b/test/powerSystem/buildUpdate.jl
@@ -48,10 +48,10 @@
     addGenerator!(build; bus = 1, active = 0.8, reactive = 0.3, status = 0)
 
     # Add Costs
-    cost!(build; label = 1, active = 2, polynomial = [0.01 * 100^2; 40 * 100; 4])
-    cost!(build; label = 2, active = 2, polynomial = [0.0266666667 * 100^2; 20 * 100; 3])
-    cost!(build; label = 3, active = 2, polynomial = [0.0266666667 * 100^2; 20 * 100; 2])
-    cost!(build; label = 4, active = 2, polynomial = [30.0 * 100; 5])
+    cost!(build; generator = 1, active = 2, polynomial = [0.01 * 100^2; 40 * 100; 4])
+    cost!(build; generator = 2, active = 2, polynomial = [0.0266666667 * 100^2; 20 * 100; 3])
+    cost!(build; generator = 3, active = 2, polynomial = [0.0266666667 * 100^2; 20 * 100; 2])
+    cost!(build; generator = 4, active = 2, polynomial = [30.0 * 100; 5])
 
     @testset "Power System Data" begin
         compstruct(load.bus, build.bus; atol = 1e-14)
@@ -94,7 +94,7 @@
     updateGenerator!(build; label = 1, loadFollowing = 5, reserve10min = 3, reactiveRamp = 4)
 
     # Update Costs
-    cost!(build; label = 4, active = 2, polynomial = [0.3 * 100^2; 15 * 100; 5])
+    cost!(build; generator = 4, active = 2, polynomial = [0.3 * 100^2; 15 * 100; 5])
 
     @testset "Power System Data" begin
         compstruct(load.bus, build.bus; atol = 1e-14)
@@ -189,10 +189,10 @@ end
     addGenerator!(build; bus = 1, active = 80e3, reactive = 30, status = 0)
 
     # Add Costs
-    cost!(build; label = 1, active = 2, polynomial = [0.01e-6; 40e-3; 4])
-    cost!(build; label = 2, active = 2, polynomial = [0.0266666667e-6; 20e-3; 3])
-    cost!(build; label = 3, active = 2, polynomial = [0.0266666667e-6; 20e-3; 2])
-    cost!(build; label = 4, active = 2, polynomial = [30.0e-3; 5])
+    cost!(build; generator = 1, active = 2, polynomial = [0.01e-6; 40e-3; 4])
+    cost!(build; generator = 2, active = 2, polynomial = [0.0266666667e-6; 20e-3; 3])
+    cost!(build; generator = 3, active = 2, polynomial = [0.0266666667e-6; 20e-3; 2])
+    cost!(build; generator = 4, active = 2, polynomial = [30.0e-3; 5])
 
     @testset "Power System Data" begin
         compstruct(load.bus, build.bus; atol = 1e-12)
@@ -248,7 +248,7 @@ end
     updateGenerator!(build; label = 1, minReactive = -10, maxReactive = 90)
 
     # Update Costs
-    cost!(build; label = 4, active = 2, polynomial = [0.3e-6; 15e-3; 5])
+    cost!(build; generator = 4, active = 2, polynomial = [0.3e-6; 15e-3; 5])
 
     @testset "Power System Data" begin
         compstruct(load.bus, build.bus; atol = 1e-12)
@@ -663,26 +663,26 @@ end
             "The concurrent definition of the keywords active and reactive is not allowed."
         )
         @test_throws err begin
-            cost!(system; label = "Generator 1", active = 2, reactive = 1, polynomial = [1.0])
+            cost!(system; generator = "Generator 1", active = 2, reactive = 1, polynomial = [1.0])
         end
 
         err = ErrorException("The cost model is missing.")
-        @test_throws err cost!(system; label = "Generator 1", polynomial = [1.0])
+        @test_throws err cost!(system; generator = "Generator 1", polynomial = [1.0])
 
         err = ErrorException(
             "The model is not allowed; it should be piecewise (1) or polynomial (2)."
         )
-        @test_throws err cost!(system; label = "Generator 1", active = 3, polynomial = [1.0])
+        @test_throws err cost!(system; generator = "Generator 1", active = 3, polynomial = [1.0])
 
         err = ErrorException(
             "An attempt to assign a polynomial function, but the function does not exist."
         )
-        @test_throws err cost!(system; label = "Generator 1", active = 2)
+        @test_throws err cost!(system; generator = "Generator 1", active = 2)
 
         err = ErrorException(
             "An attempt to assign a piecewise function, but the function does not exist."
         )
-        @test_throws err cost!(system; label = "Generator 1", active = 1)
+        @test_throws err cost!(system; generator = "Generator 1", active = 1)
 
         @test_throws LoadError @eval @generator(label = "Generator ?", actives = 1)
     end