Merge pull request #345 from NREL/obj-incentives

Avoid modifying LCC with Obj Func Incentives

CHANGELOG.md

@@ -23,6 +23,10 @@ Classify the change according to the following categories:
     ### Deprecated
     ### Removed
 
+## Develop 2024-01-16
+### Fixed
+- In `reopt.jl`, group objective function incentives (into **ObjectivePenalties**) and avoid directly modifying m[:Costs]. Previously, some of these were incorrectly included in the reported **Financial.lcc**. 
+
 ## v0.39.1
 ### Changed
 - Changed testing suite from using Xpress to using HiGHS, an open-source solver.  This has led to a reduction in the number of tests due to incompatibility with indicator constraints.

src/core/reopt.jl

@@ -247,6 +247,7 @@ function build_reopt!(m::JuMP.AbstractModel, p::REoptInputs)
     m[:GHPOMCosts] = 0.0
 	m[:AvoidedCapexByGHP] = 0.0
 	m[:ResidualGHXCapCost] = 0.0
+	m[:ObjectivePenalties] = 0.0
 
 	if !isempty(p.techs.all)
 		add_tech_size_constraints(m, p)
@@ -441,12 +442,7 @@ function build_reopt!(m::JuMP.AbstractModel, p::REoptInputs)
 		m[:TotalElecBill] * (1 - p.s.financial.offtaker_tax_rate_fraction) -
 
         # Subtract Incentives, which are taxable
-		m[:TotalProductionIncentive] * (1 - p.s.financial.owner_tax_rate_fraction) +
-
-		# Comfort limit violation costs
-		#TODO: add this to objective like SOC incentive below and 
-		#don't then subtract out when setting lcc in results/financial.jl
-		m[:dvComfortLimitViolationCost] + 
+		m[:TotalProductionIncentive] * (1 - p.s.financial.owner_tax_rate_fraction) + 
 
 		# Additional annual costs, tax deductible for owner (only applies when `off_grid_flag` is true)
 		p.s.financial.offgrid_other_annual_costs * p.pwf_om * (1 - p.s.financial.owner_tax_rate_fraction) +
@@ -470,36 +466,23 @@ function build_reopt!(m::JuMP.AbstractModel, p::REoptInputs)
 		add_to_expression!(Costs, m[:Lifecycle_Emissions_Cost_Health])
 	end
 
-	@expression(m, Objective,
-		m[:Costs]
-	)
-		
+	## Modify objective with incentives that are not part of the LCC
+	# 1. Comfort limit violation costs
+	m[:ObjectivePenalties] += m[:dvComfortLimitViolationCost]
+	# 2. Incentive to keep SOC high
 	if !(isempty(p.s.storage.types.elec)) && p.s.settings.add_soc_incentive
-		# Incentive to keep SOC high
-		add_to_expression!(
-			Objective, 
-			- sum(
+		m[:ObjectivePenalties] += -1 * sum(
 				m[:dvStoredEnergy][b, ts] for b in p.s.storage.types.elec, ts in p.time_steps
 			) / (8760. / p.hours_per_time_step)
-		)
 	end
+	# 3. Incentive to minimize unserved load in each outage, not just the max over outage start times
 	if !isempty(p.s.electric_utility.outage_durations)
-		# Incentive to minimize unserved load in each outage, not just the max over outage start times
-		add_to_expression!(
-			Objective, 
-			sum(sum(0.0001 * m[:dvUnservedLoad][s, tz, ts] for ts in 1:p.s.electric_utility.outage_durations[s]) for s in p.s.electric_utility.scenarios, tz in p.s.electric_utility.outage_start_time_steps)
-		)
+		m[:ObjectivePenalties] += sum(sum(0.0001 * m[:dvUnservedLoad][s, tz, ts] for ts in 1:p.s.electric_utility.outage_durations[s]) 
+			for s in p.s.electric_utility.scenarios, tz in p.s.electric_utility.outage_start_time_steps)
 	end
 
-	@objective(m, Min, m[:Objective])
-
-	# if !(isempty(p.s.storage.types.elec)) && p.s.settings.add_soc_incentive # Keep SOC high
-	# 	@objective(m, Min, m[:Costs] - 
-	# 	sum(m[:dvStoredEnergy][b, ts] for b in p.s.storage.types.elec, ts in p.time_steps) /
-	# 		(8760. / p.hours_per_time_step)
-	# 	)
-
-	# end
+	# Set model objective 
+	@objective(m, Min, m[:Costs] + m[:ObjectivePenalties] )
 
 	for b in p.s.storage.types.elec
 		if p.s.storage.attr[b].model_degradation

src/results/financial.jl

@@ -38,9 +38,6 @@ calculated in combine_results function if BAU scenario is run:
 """
 function add_financial_results(m::JuMP.AbstractModel, p::REoptInputs, d::Dict; _n="")
     r = Dict{String, Float64}()
-    if !(Symbol("dvComfortLimitViolationCost"*_n) in keys(m.obj_dict))
-        m[Symbol("dvComfortLimitViolationCost"*_n)] = 0.0
-    end
     if !(Symbol("TotalProductionIncentive"*_n) in keys(m.obj_dict)) # not currently included in multi-node modeling b/c these constraints require binary vars.
         m[Symbol("TotalProductionIncentive"*_n)] = 0.0
     end
@@ -54,7 +51,8 @@ function add_financial_results(m::JuMP.AbstractModel, p::REoptInputs, d::Dict; _
         m[Symbol("GHPCapCosts"*_n)] = 0.0
     end
 
-    r["lcc"] = value(m[Symbol("Costs"*_n)]) + 0.0001 * value(m[Symbol("MinChargeAdder"*_n)]) - value(m[Symbol("dvComfortLimitViolationCost"*_n)])
+    r["lcc"] = value(m[Symbol("Costs"*_n)]) + 0.0001 * value(m[Symbol("MinChargeAdder"*_n)])
+
     r["lifecycle_om_costs_before_tax"] = value(m[Symbol("TotalPerUnitSizeOMCosts"*_n)] + 
                                            m[Symbol("TotalPerUnitProdOMCosts"*_n)] + m[Symbol("TotalPerUnitHourOMCosts"*_n)] + m[Symbol("GHPOMCosts"*_n)])
 

test/test_with_xpress.jl

@@ -1479,7 +1479,7 @@ end
             @test results["Site"]["total_renewable_energy_fraction_bau"] ≈ 0.132118 atol=1e-3 # 0.1354 atol=1e-3
             # CO2 emissions - totals ≈  from grid, from fuelburn, ER, $/tCO2 breakeven
             @test results["Site"]["lifecycle_emissions_reduction_CO2_fraction"] ≈ 0.8 atol=1e-3 # 0.8
-            @test results["Financial"]["breakeven_cost_of_emissions_reduction_per_tonne_CO2"] ≈ 373.9 atol=1e-1
+            @test results["Financial"]["breakeven_cost_of_emissions_reduction_per_tonne_CO2"] ≈ 374.0 atol=1e-1
             @test results["Site"]["annual_emissions_tonnes_CO2"] ≈ 14.2 atol=1
             @test results["Site"]["annual_emissions_tonnes_CO2_bau"] ≈ 70.99 atol=1
             @test results["Site"]["annual_emissions_from_fuelburn_tonnes_CO2"] ≈ 0.0 atol=1 # 0.0