Battery storage cost constant version 2

src/core/energy_storage/electric_storage.jl

@@ -148,10 +148,13 @@ end
     can_grid_charge::Bool = off_grid_flag ? false : true
     installed_cost_per_kw::Real = 910.0
     installed_cost_per_kwh::Real = 455.0
+    installed_cost_constant::Real = 0.0
     replace_cost_per_kw::Real = 715.0
     replace_cost_per_kwh::Real = 318.0
+    replace_cost_constant::Real = 0.0
     inverter_replacement_year::Int = 10
     battery_replacement_year::Int = 10
+    cost_constant_replacement_year::Int = 10
     macrs_option_years::Int = 7
     macrs_bonus_fraction::Float64 = 0.8
     macrs_itc_reduction::Float64 = 0.5
@@ -180,10 +183,13 @@ Base.@kwdef struct ElectricStorageDefaults
     can_grid_charge::Bool = off_grid_flag ? false : true
     installed_cost_per_kw::Real = 910.0
     installed_cost_per_kwh::Real = 455.0
+    installed_cost_constant::Real = 0.0
     replace_cost_per_kw::Real = 715.0
     replace_cost_per_kwh::Real = 318.0
+    replace_cost_constant::Real = 0.0
     inverter_replacement_year::Int = 10
     battery_replacement_year::Int = 10
+    cost_constant_replacement_year::Int = 10
     macrs_option_years::Int = 7
     macrs_bonus_fraction::Float64 = 0.8
     macrs_itc_reduction::Float64 = 0.5
@@ -218,10 +224,13 @@ struct ElectricStorage <: AbstractElectricStorage
     can_grid_charge::Bool
     installed_cost_per_kw::Real
     installed_cost_per_kwh::Real
+    installed_cost_constant::Real
     replace_cost_per_kw::Real
     replace_cost_per_kwh::Real
+    replace_cost_constant::Real
     inverter_replacement_year::Int
     battery_replacement_year::Int
+    cost_constant_replacement_year::Int
     macrs_option_years::Int
     macrs_bonus_fraction::Float64
     macrs_itc_reduction::Float64
@@ -233,6 +242,7 @@ struct ElectricStorage <: AbstractElectricStorage
     grid_charge_efficiency::Float64
     net_present_cost_per_kw::Real
     net_present_cost_per_kwh::Real
+    net_present_cost_cost_constant::Real
     model_degradation::Bool
     degradation::Degradation
     minimum_avg_soc_fraction::Float64
@@ -274,6 +284,19 @@ struct ElectricStorage <: AbstractElectricStorage
 
         net_present_cost_per_kwh -= s.total_rebate_per_kwh
 
+        net_present_cost_cost_constant = effective_cost(;
+            itc_basis = s.installed_cost_constant,
+            replacement_cost = s.cost_constant_replacement_year >= f.analysis_years ? 0.0 : s.replace_cost_constant,
+            replacement_year = s.cost_constant_replacement_year,
+            discount_rate = f.owner_discount_rate_fraction,
+            tax_rate = f.owner_tax_rate_fraction,
+            itc = s.total_itc_fraction,
+            macrs_schedule = s.macrs_option_years == 7 ? f.macrs_seven_year : f.macrs_five_year,
+            macrs_bonus_fraction = s.macrs_bonus_fraction,
+            macrs_itc_reduction = s.macrs_itc_reduction
+
+        )
+
         if haskey(d, :degradation)
             degr = Degradation(;dictkeys_tosymbols(d[:degradation])...)
         else
@@ -283,13 +306,15 @@ struct ElectricStorage <: AbstractElectricStorage
         # copy the replace_costs in case we need to change them
         replace_cost_per_kw = s.replace_cost_per_kw 
         replace_cost_per_kwh = s.replace_cost_per_kwh
+        replace_cost_constant = s.replace_cost_constant
         if s.model_degradation
             if haskey(d, :replace_cost_per_kw) && d[:replace_cost_per_kw] != 0.0 || 
                 haskey(d, :replace_cost_per_kwh) && d[:replace_cost_per_kwh] != 0.0
                 @warn "Setting ElectricStorage replacement costs to zero. Using degradation.maintenance_cost_per_kwh instead."
             end
             replace_cost_per_kw = 0.0
             replace_cost_per_kwh = 0.0
+            replace_cost_constant = 0.0
         end
 
         return new(
@@ -305,10 +330,13 @@ struct ElectricStorage <: AbstractElectricStorage
             s.can_grid_charge,
             s.installed_cost_per_kw,
             s.installed_cost_per_kwh,
+            s.installed_cost_constant,
             replace_cost_per_kw,
             replace_cost_per_kwh,
+            replace_cost_constant,
             s.inverter_replacement_year,
             s.battery_replacement_year,
+            s.cost_constant_replacement_year,
             s.macrs_option_years,
             s.macrs_bonus_fraction,
             s.macrs_itc_reduction,
@@ -320,6 +348,7 @@ struct ElectricStorage <: AbstractElectricStorage
             s.grid_charge_efficiency,
             net_present_cost_per_kw,
             net_present_cost_per_kwh,
+            net_present_cost_cost_constant,
             s.model_degradation,
             degr,
             s.minimum_avg_soc_fraction

src/core/reopt.jl

@@ -358,9 +358,18 @@ function build_reopt!(m::JuMP.AbstractModel, p::REoptInputs)
         end
     end
 
+	# indicator function to say: if the energy capacity is greater than zero, then the dvBatteryIncluded binary is 1
+	@constraint(m, [b in p.s.storage.types.elec],
+		m[:dvBatteryIncluded][b] => {m[:dvStorageEnergy][b] >= 0}) # Question: is the >= actually just a greater-than sign?
+
+	# indicator function to say: if the energy capacity is zero, then the dvBatteryIncluded binary is 0
+	@constraint(m, [b in p.s.storage.types.elec],
+		!m[:dvBatteryIncluded][b] => {m[:dvStorageEnergy][b] == 0})
+
 	@expression(m, TotalStorageCapCosts, p.third_party_factor * (
 		sum( p.s.storage.attr[b].net_present_cost_per_kw * m[:dvStoragePower][b] for b in p.s.storage.types.elec) + 
-		sum( p.s.storage.attr[b].net_present_cost_per_kwh * m[:dvStorageEnergy][b] for b in p.s.storage.types.all )
+		sum( p.s.storage.attr[b].net_present_cost_per_kwh * m[:dvStorageEnergy][b] for b in p.s.storage.types.all ) +
+		sum( p.s.storage.attr[b].net_present_cost_cost_constant * m[:dvBatteryIncluded][b] for b in p.s.storage.types.elec)
 	))
 
 	@expression(m, TotalPerUnitSizeOMCosts, p.third_party_factor * p.pwf_om *
@@ -565,6 +574,7 @@ function add_variables!(m::JuMP.AbstractModel, p::REoptInputs)
 		dvPeakDemandMonth[p.months, 1:p.s.electric_tariff.n_monthly_demand_tiers] >= 0  # Peak electrical power demand during month m [kW]
 		MinChargeAdder >= 0
         binGHP[p.ghp_options], Bin  # Can be <= 1 if require_ghp_purchase=0, and is ==1 if require_ghp_purchase=1
+		dvBatteryIncluded[p.s.storage.types.all], Bin # 0 if no battery is included, 1 if battery is included
 	end
 
 	if !isempty(p.techs.gen)  # Problem becomes a MILP

src/results/electric_storage.jl

@@ -32,7 +32,8 @@ function add_electric_storage_results(m::JuMP.AbstractModel, p::REoptInputs, d::
         r["storage_to_load_series_kw"] = round.(value.(discharge), digits=3)
 
         r["initial_capital_cost"] = r["size_kwh"] * p.s.storage.attr[b].installed_cost_per_kwh +
-            r["size_kw"] * p.s.storage.attr[b].installed_cost_per_kw
+            r["size_kw"] * p.s.storage.attr[b].installed_cost_per_kw +
+            p.s.storage.attr[b].installed_cost_constant
 
         if p.s.storage.attr[b].model_degradation
             r["state_of_health"] = value.(m[:SOH]).data / value.(m[:dvStorageEnergy])["ElectricStorage"];

src/results/financial.jl

@@ -146,7 +146,8 @@ function initial_capex(m::JuMP.AbstractModel, p::REoptInputs; _n="")
     for b in p.s.storage.types.elec
         if p.s.storage.attr[b].max_kw > 0
             initial_capex += p.s.storage.attr[b].installed_cost_per_kw * value.(m[Symbol("dvStoragePower"*_n)])[b] + 
-                p.s.storage.attr[b].installed_cost_per_kwh * value.(m[Symbol("dvStorageEnergy"*_n)])[b]
+                p.s.storage.attr[b].installed_cost_per_kwh * value.(m[Symbol("dvStorageEnergy"*_n)])[b] +
+                p.s.storage.attr[b].installed_cost_constant
         end
     end
 
@@ -238,12 +239,20 @@ function replacement_costs_future_and_present(m::JuMP.AbstractModel, p::REoptInp
         else
             future_cost_storage = p.s.storage.attr[b].replace_cost_per_kwh * value.(m[Symbol("dvStorageEnergy"*_n)])[b]
         end
-        future_cost += future_cost_inverter + future_cost_storage
+        if p.s.storage.attr[b].cost_constant_replacement_year >= p.s.financial.analysis_years
+            future_cost_cost_constant = 0
+        else
+            future_cost_cost_constant = p.s.storage.attr[b].replace_cost_constant
+        end
+
+        future_cost += future_cost_inverter + future_cost_storage + future_cost_cost_constant
 
         present_cost += future_cost_inverter * (1 - p.s.financial.owner_tax_rate_fraction) / 
             ((1 + p.s.financial.owner_discount_rate_fraction)^p.s.storage.attr[b].inverter_replacement_year)
         present_cost += future_cost_storage * (1 - p.s.financial.owner_tax_rate_fraction) / 
             ((1 + p.s.financial.owner_discount_rate_fraction)^p.s.storage.attr[b].battery_replacement_year)
+        present_cost += future_cost_cost_constant * (1 - p.s.financial.owner_tax_rate_fraction) / 
+            ((1 + p.s.financial.owner_discount_rate_fraction)^p.s.storage.attr[b].cost_constant_replacement_year)  
     end
 
     if !isempty(p.techs.gen) # Generator replacement