Prevent simultaneous charge/discharge plus other minor improvements

CHANGELOG.md

@@ -5,7 +5,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## Guidelines
-- When making a Pull Request into `develop` start a new double-hash header for "Develop - YYYY-MM-DD"
+- When working in feature branch, start a new double-hash header with the name of the branch and record changes under that
+- When merging `develop` into a feature branch, keep the feature branch section and the "Develop" section separate to simplify merge conflicts
+- When making a Pull Request into `develop`, merge the feature branch section into the "Develop" section (if it exists), else rename the feature branch header to "Develop"
 - When making a Pull Request into `master` change "Develop" to the next version number
 
 ### Formatting
@@ -23,6 +25,22 @@ Classify the change according to the following categories:
     ### Deprecated
     ### Removed
 
+## Develop #prevent-simul-charge-discharge
+### Changed
+- Replace all `1/p.s.settings.time_steps_per_hour` with `p.hours_per_time_step` for simplicity/consistency
+- Rename function `add_storage_sum_constraints` to `add_storage_sum_grid_constraints` for clarity
+### Added
+- Constraints to prevent simultaneous charge/discharge of storage
+- Specify in docstrings that **PV** **max_kw** and **size_kw** are kW-DC
+- Add the Logging package to `test/Project.toml` because it is used in `runtests.jl`
+### Fixed
+- Force **ElectricLoad** **critical_load_kw** to be _nothing_ when **off_grid_flag** is _true_ (**critical_load_fraction** was already being forced to 1, but the user was still able to get around this by providing **critical_load_kw**)
+- Removed looping over storage name in functions `add_hot_thermal_storage_dispatch_constraints` and `add_cold_thermal_storage_dispatch_constraints` because this loop is already done when calling these functions and storage name is passed in as argument `b`
+- Remove extraneous line of code in `results/wind.jl`
+- Change type of **value_of_lost_load** in **FinancialInputs** struct to fix convert error when user provides an _Int_
+- Change international location in "Solar Dataset" test set from Cameroon to Oulu because the locations in the NSRDB have been expanded significantly so there is now an NSRDB point at Cameroon
+- Handle edge case where the values of **outage_start_time_steps** and **outage_durations** makes an outage extend beyond the end of the year. The outage will now wrap around to the beginning of the year.
+
 ## v0.48.0
 ### Added
 - Added new file `src/core/ASHP.jl` with new technology **ASHP**, which uses electricity as input and provides heating and/or cooling as output; load balancing and technology-specific constraints have been updated and added accordingly

src/constraints/outage_constraints.jl

@@ -2,8 +2,8 @@
 function add_dv_UnservedLoad_constraints(m,p)
     # Effective load balance
     @constraint(m, [s in p.s.electric_utility.scenarios, tz in p.s.electric_utility.outage_start_time_steps, ts in p.s.electric_utility.outage_time_steps],
-        m[:dvUnservedLoad][s, tz, ts] == p.s.electric_load.critical_loads_kw[tz+ts-1]
-        - sum(  m[:dvMGRatedProduction][t, s, tz, ts] * (p.production_factor[t, tz+ts-1] + p.unavailability[t][tz+ts-1]) * p.levelization_factor[t]
+        m[:dvUnservedLoad][s, tz, ts] == p.s.electric_load.critical_loads_kw[time_step_wrap_around(tz+ts-1, time_steps_per_hour=p.s.settings.time_steps_per_hour)]
+        - sum(  m[:dvMGRatedProduction][t, s, tz, ts] * (p.production_factor[t, time_step_wrap_around(tz+ts-1, time_steps_per_hour=p.s.settings.time_steps_per_hour)] + p.unavailability[t][time_step_wrap_around(tz+ts-1, time_steps_per_hour=p.s.settings.time_steps_per_hour)]) * p.levelization_factor[t]
               - m[:dvMGProductionToStorage][t, s, tz, ts] - m[:dvMGCurtail][t, s, tz, ts]
             for t in p.techs.elec
         )
@@ -22,7 +22,7 @@ end
 
 function add_outage_cost_constraints(m,p)
     @constraint(m, [s in p.s.electric_utility.scenarios, tz in p.s.electric_utility.outage_start_time_steps],
-        m[:dvMaxOutageCost][s] >= p.pwf_e * sum(p.value_of_lost_load_per_kwh[tz+ts-1] * m[:dvUnservedLoad][s, tz, ts] for ts in 1:p.s.electric_utility.outage_durations[s])
+        m[:dvMaxOutageCost][s] >= p.pwf_e * sum(p.value_of_lost_load_per_kwh[time_step_wrap_around(tz+ts-1, time_steps_per_hour=p.s.settings.time_steps_per_hour)] * m[:dvUnservedLoad][s, tz, ts] for ts in 1:p.s.electric_utility.outage_durations[s])
     )
 
     @expression(m, ExpectedOutageCost,
@@ -116,7 +116,7 @@ function add_MG_production_constraints(m,p)
 	# Electrical production sent to storage or export must be less than technology's rated production
 	@constraint(m, [t in p.techs.elec, s in p.s.electric_utility.scenarios, tz in p.s.electric_utility.outage_start_time_steps, ts in p.s.electric_utility.outage_time_steps],
 		m[:dvMGProductionToStorage][t, s, tz, ts] + m[:dvMGCurtail][t, s, tz, ts] <=
-		(p.production_factor[t, tz+ts-1] + p.unavailability[t][tz+ts-1]) * p.levelization_factor[t] * m[:dvMGRatedProduction][t, s, tz, ts]
+		(p.production_factor[t, time_step_wrap_around(tz+ts-1, time_steps_per_hour=p.s.settings.time_steps_per_hour)] + p.unavailability[t][time_step_wrap_around(tz+ts-1, time_steps_per_hour=p.s.settings.time_steps_per_hour)]) * p.levelization_factor[t] * m[:dvMGRatedProduction][t, s, tz, ts]
     )
 
     @constraint(m, [t in p.techs.elec, s in p.s.electric_utility.scenarios, tz in p.s.electric_utility.outage_start_time_steps, ts in p.s.electric_utility.outage_time_steps], 
@@ -138,7 +138,7 @@ function add_MG_Gen_fuel_burn_constraints(m,p)
     # Define dvMGFuelUsed by summing over outage time_steps.
     @constraint(m, [t in p.techs.gen, s in p.s.electric_utility.scenarios, tz in p.s.electric_utility.outage_start_time_steps],
         m[:dvMGFuelUsed][t, s, tz] == fuel_slope_gal_per_kwhe * p.hours_per_time_step * p.levelization_factor[t] *
-        sum( (p.production_factor[t, tz+ts-1] + p.unavailability[t][tz+ts-1]) * m[:dvMGRatedProduction][t, s, tz, ts] for ts in 1:p.s.electric_utility.outage_durations[s])
+        sum( (p.production_factor[t, time_step_wrap_around(tz+ts-1, time_steps_per_hour=p.s.settings.time_steps_per_hour)] + p.unavailability[t][time_step_wrap_around(tz+ts-1, time_steps_per_hour=p.s.settings.time_steps_per_hour)]) * m[:dvMGRatedProduction][t, s, tz, ts] for ts in 1:p.s.electric_utility.outage_durations[s])
         + fuel_intercept_gal_per_hr * p.hours_per_time_step * 
         sum( m[:binMGGenIsOnInTS][s, tz, ts] for ts in 1:p.s.electric_utility.outage_durations[s])
     )
@@ -287,6 +287,14 @@ function add_MG_storage_dispatch_constraints(m,p)
         )
     )
 
+	# Prevent simultaneous charge and discharge by limitting charging alone to not make the SOC exceed 100%
+    @constraint(m, [ts in p.time_steps_without_grid],
+        m[:dvStorageEnergy]["ElectricStorage"] >= m[:dvMGStoredEnergy][s, tz, ts-1] + p.hours_per_time_step * (  
+            p.s.storage.attr["ElectricStorage"].charge_efficiency * sum(m[:dvMGProductionToStorage][t, s, tz, ts] for t in p.techs.elec) 
+        )
+    )
+
+    # Min SOC
     if p.s.storage.attr["ElectricStorage"].soc_min_applies_during_outages
         # Minimum state of charge
         @constraint(m, [s in p.s.electric_utility.scenarios, tz in p.s.electric_utility.outage_start_time_steps, ts in p.s.electric_utility.outage_time_steps],

src/constraints/storage_constraints.jl

@@ -50,21 +50,35 @@ end
 
 function add_elec_storage_dispatch_constraints(m, p, b; _n="")
 
-	# Constraint (4g): state-of-charge for electrical storage - with grid
+	# Constraint (4g)-1: state-of-charge for electrical storage - with grid
 	@constraint(m, [ts in p.time_steps_with_grid],
         m[Symbol("dvStoredEnergy"*_n)][b, ts] == m[Symbol("dvStoredEnergy"*_n)][b, ts-1] + p.hours_per_time_step * (  
             sum(p.s.storage.attr[b].charge_efficiency * m[Symbol("dvProductionToStorage"*_n)][b, t, ts] for t in p.techs.elec) 
             + p.s.storage.attr[b].grid_charge_efficiency * m[Symbol("dvGridToStorage"*_n)][b, ts] 
             - m[Symbol("dvDischargeFromStorage"*_n)][b,ts] / p.s.storage.attr[b].discharge_efficiency
         )
 	)
-
-	# Constraint (4h): state-of-charge for electrical storage - no grid
+	# Constraint (4g)-2: state-of-charge for electrical storage - no grid
 	@constraint(m, [ts in p.time_steps_without_grid],
         m[Symbol("dvStoredEnergy"*_n)][b, ts] == m[Symbol("dvStoredEnergy"*_n)][b, ts-1] + p.hours_per_time_step * (  
             sum(p.s.storage.attr[b].charge_efficiency * m[Symbol("dvProductionToStorage"*_n)][b,t,ts] for t in p.techs.elec) 
             - m[Symbol("dvDischargeFromStorage"*_n)][b, ts] / p.s.storage.attr[b].discharge_efficiency
         )
+    )	
+
+	# Constraint (4h): prevent simultaneous charge and discharge by limitting charging alone to not make the SOC exceed 100%
+    # (4h)-1: with grid
+	@constraint(m, [ts in p.time_steps_with_grid],
+        m[Symbol("dvStorageEnergy"*_n)][b] >= m[Symbol("dvStoredEnergy"*_n)][b, ts-1] + p.hours_per_time_step * (  
+            sum(p.s.storage.attr[b].charge_efficiency * m[Symbol("dvProductionToStorage"*_n)][b, t, ts] for t in p.techs.elec) 
+            + p.s.storage.attr[b].grid_charge_efficiency * m[Symbol("dvGridToStorage"*_n)][b, ts] 
+        )
+	)
+	# (4h)-2: no grid
+	@constraint(m, [ts in p.time_steps_without_grid],
+        m[Symbol("dvStorageEnergy"*_n)][b] >= m[Symbol("dvStoredEnergy"*_n)][b, ts-1] + p.hours_per_time_step * (  
+            sum(p.s.storage.attr[b].charge_efficiency * m[Symbol("dvProductionToStorage"*_n)][b,t,ts] for t in p.techs.elec) 
+        )
     )
 
 	# Constraint (4i)-1: Dispatch to electrical storage is no greater than power capacity
@@ -104,16 +118,24 @@ end
 function add_hot_thermal_storage_dispatch_constraints(m, p, b; _n="")
 
     # Constraint (4j)-1: Reconcile state-of-charge for (hot) thermal storage
-	@constraint(m, [b in p.s.storage.types.hot, ts in p.time_steps],
-    m[Symbol("dvStoredEnergy"*_n)][b,ts] == m[Symbol("dvStoredEnergy"*_n)][b,ts-1] + (1/p.s.settings.time_steps_per_hour) * (
-        p.s.storage.attr[b].charge_efficiency * sum(m[Symbol("dvHeatToStorage"*_n)][b,t,q,ts] for t in union(p.techs.heating, p.techs.chp), q in p.heating_loads) -
-        sum(m[Symbol("dvHeatFromStorage"*_n)][b,q,ts] for q in p.heating_loads) / p.s.storage.attr[b].discharge_efficiency -
-        p.s.storage.attr[b].thermal_decay_rate_fraction * m[Symbol("dvStorageEnergy"*_n)][b]
+	@constraint(m, [ts in p.time_steps],
+        m[Symbol("dvStoredEnergy"*_n)][b,ts] == m[Symbol("dvStoredEnergy"*_n)][b,ts-1] + p.hours_per_time_step * (
+            p.s.storage.attr[b].charge_efficiency * sum(m[Symbol("dvHeatToStorage"*_n)][b,t,q,ts] for t in union(p.techs.heating, p.techs.chp), q in p.heating_loads) -
+            sum(m[Symbol("dvHeatFromStorage"*_n)][b,q,ts] for q in p.heating_loads) / p.s.storage.attr[b].discharge_efficiency -
+            p.s.storage.attr[b].thermal_decay_rate_fraction * m[Symbol("dvStorageEnergy"*_n)][b]
         )
     )
 
+    # Prevent simultaneous charge and discharge by limitting charging alone to not make the SOC exceed 100%
+	@constraint(m, [ts in p.time_steps],
+        m[Symbol("dvStorageEnergy"*_n)][b] >= m[Symbol("dvStoredEnergy"*_n)][b,ts-1] + p.hours_per_time_step * (  
+            p.s.storage.attr[b].charge_efficiency * sum(m[Symbol("dvHeatToStorage"*_n)][b,t,q,ts] for t in union(p.techs.heating, p.techs.chp), q in p.heating_loads)
+            - p.s.storage.attr[b].thermal_decay_rate_fraction * m[Symbol("dvStorageEnergy"*_n)][b]
+        )
+    )
+
     #Constraint (4n)-1: Dispatch to and from thermal storage is no greater than power capacity
-	@constraint(m, [b in p.s.storage.types.hot, ts in p.time_steps],
+	@constraint(m, [ts in p.time_steps],
         m[Symbol("dvStoragePower"*_n)][b] >= 
         sum(m[Symbol("dvHeatFromStorage"*_n)][b,q,ts] + 
         sum(m[Symbol("dvHeatToStorage"*_n)][b,t,q,ts] for t in union(p.techs.heating, p.techs.chp))
@@ -122,14 +144,14 @@ function add_hot_thermal_storage_dispatch_constraints(m, p, b; _n="")
     # TODO missing thermal storage constraints from API ???
 
     # Constraint (4o): Discharge from storage is equal to sum of heat from storage for all qualities
-    @constraint(m, HeatDischargeReconciliation[b in p.s.storage.types.hot, ts in p.time_steps],
+    @constraint(m, HeatDischargeReconciliation[ts in p.time_steps],
         m[Symbol("dvDischargeFromStorage"*_n)][b,ts] == 
         sum(m[Symbol("dvHeatFromStorage"*_n)][b,q,ts] for q in p.heating_loads)
     )
 
     #Do not allow GHP to charge storage
     if !isempty(p.techs.ghp)
-        for b in p.s.storage.types.hot, t in p.techs.ghp, q in p.heating_loads, ts in p.time_steps
+        for t in p.techs.ghp, q in p.heating_loads, ts in p.time_steps
             fix(m[Symbol("dvHeatToStorage"*_n)][b,t,q,ts], 0.0, force=true)
         end
     end
@@ -140,36 +162,44 @@ function add_cold_thermal_storage_dispatch_constraints(m, p, b; _n="")
 
     # Constraint (4f)-2: (Cold) Thermal production sent to storage or grid must be less than technology's rated production
 	if !isempty(p.techs.cooling)
-		@constraint(m, CoolingTechProductionFlowCon[b in p.s.storage.types.cold, t in p.techs.cooling, ts in p.time_steps],
+		@constraint(m, CoolingTechProductionFlowCon[t in p.techs.cooling, ts in p.time_steps],
     	        m[Symbol("dvProductionToStorage"*_n)][b,t,ts]  <=
 				m[Symbol("dvCoolingProduction"*_n)][t,ts]
 				)
 	end
 
     # Constraint (4j)-2: Reconcile state-of-charge for (cold) thermal storage
-	@constraint(m, ColdTESInventoryCon[b in p.s.storage.types.cold, ts in p.time_steps],
-    m[Symbol("dvStoredEnergy"*_n)][b,ts] == m[Symbol("dvStoredEnergy"*_n)][b,ts-1] + (1/p.s.settings.time_steps_per_hour) * (
-        sum(p.s.storage.attr[b].charge_efficiency * m[Symbol("dvProductionToStorage"*_n)][b,t,ts] for t in p.techs.cooling) -
-        m[Symbol("dvDischargeFromStorage"*_n)][b,ts]/p.s.storage.attr[b].discharge_efficiency -
-        p.s.storage.attr[b].thermal_decay_rate_fraction * m[Symbol("dvStorageEnergy"*_n)][b]
+	@constraint(m, ColdTESInventoryCon[ts in p.time_steps],
+        m[Symbol("dvStoredEnergy"*_n)][b,ts] == m[Symbol("dvStoredEnergy"*_n)][b,ts-1] + p.hours_per_time_step * (
+            sum(p.s.storage.attr[b].charge_efficiency * m[Symbol("dvProductionToStorage"*_n)][b,t,ts] for t in p.techs.cooling) -
+            m[Symbol("dvDischargeFromStorage"*_n)][b,ts]/p.s.storage.attr[b].discharge_efficiency -
+            p.s.storage.attr[b].thermal_decay_rate_fraction * m[Symbol("dvStorageEnergy"*_n)][b]
+        )
+    )
+
+    # Prevent simultaneous charge and discharge by limitting charging alone to not make the SOC exceed 100%
+	@constraint(m, [ts in p.time_steps],
+        m[Symbol("dvStorageEnergy"*_n)][b] >= m[Symbol("dvStoredEnergy"*_n)][b,ts-1] + p.hours_per_time_step * (  
+            p.s.storage.attr[b].charge_efficiency * sum(m[Symbol("dvProductionToStorage"*_n)][b,t,ts] for t in p.techs.cooling)
+            - p.s.storage.attr[b].thermal_decay_rate_fraction * m[Symbol("dvStorageEnergy"*_n)][b]
         )
     )
 
     #Constraint (4n)-2: Dispatch to and from thermal storage is no greater than power capacity
-    @constraint(m, [b in p.s.storage.types.cold, ts in p.time_steps],
+    @constraint(m, [ts in p.time_steps],
         m[Symbol("dvStoragePower"*_n)][b] >= m[Symbol("dvDischargeFromStorage"*_n)][b,ts] + 
         sum(m[Symbol("dvProductionToStorage"*_n)][b,t,ts] for t in p.techs.cooling)
     )
 
     #Do not allow GHP to charge storage
     if !isempty(p.techs.ghp)
-        for b in p.s.storage.types.cold, t in p.techs.ghp, ts in p.time_steps
+        for t in p.techs.ghp, ts in p.time_steps
                     fix(m[Symbol("dvProductionToStorage"*_n)][b,t,ts], 0.0, force=true)
         end
     end
 end
 
-function add_storage_sum_constraints(m, p; _n="")
+function add_storage_sum_grid_constraints(m, p; _n="")
 
 	##Constraint (8c): Grid-to-storage no greater than grid purchases 
 	@constraint(m, [ts in p.time_steps_with_grid],

src/constraints/thermal_tech_constraints.jl

@@ -15,7 +15,7 @@ function add_boiler_tech_constraints(m, p; _n="")
     )
     if "Boiler" in p.techs.boiler  # ExistingBoiler does not have om_cost_per_kwh
         m[:TotalBoilerPerUnitProdOMCosts] = @expression(m, p.third_party_factor * p.pwf_om *
-            sum(p.s.boiler.om_cost_per_kwh / p.s.settings.time_steps_per_hour *
+            sum(p.s.boiler.om_cost_per_kwh * p.hours_per_time_step *
             m[Symbol("dvHeatingProduction"*_n)]["Boiler",q,ts] for q in p.heating_loads, ts in p.time_steps)
         )
     else

src/core/bau_inputs.jl

@@ -287,7 +287,7 @@ function setup_bau_emissions_inputs(p::REoptInputs, s_bau::BAUScenario, generato
         bau_grid_to_load = [max(i,0) for i in bau_grid_to_load]
     end
 
-    bau_grid_emissions_lb_CO2_per_year = sum(p.s.electric_utility.emissions_factor_series_lb_CO2_per_kwh .* bau_grid_to_load) / p.s.settings.time_steps_per_hour
+    bau_grid_emissions_lb_CO2_per_year = sum(p.s.electric_utility.emissions_factor_series_lb_CO2_per_kwh .* bau_grid_to_load) * p.hours_per_time_step
     bau_emissions_lb_CO2_per_year += bau_grid_emissions_lb_CO2_per_year
 
     ## Generator emissions (during outages)

src/core/electric_load.jl

@@ -105,9 +105,15 @@ mutable struct ElectricLoad  # mutable to adjust (critical_)loads_kw based off o
         min_load_met_annual_fraction::Real = off_grid_flag ? 0.99999 : 1.0 # if off grid, 99.999%, else must be 100%. Applied to each time_step as a % of electric load.
         )
 
-        if off_grid_flag  && !(critical_load_fraction == 1.0)
-            @warn "ElectricLoad critical_load_fraction must be 1.0 (100%) for off-grid scenarios. Any other value will be overriden when `off_grid_flag` is true. If you wish to alter the load profile or load met, adjust the loads_kw or min_load_met_annual_fraction."
-            critical_load_fraction = 1.0
+        if off_grid_flag
+            if !isnothing(critical_loads_kw)
+                @warn "ElectricLoad critical_loads_kw will be ignored because `off_grid_flag` is true. If you wish to alter the load profile or load met, adjust the loads_kw or min_load_met_annual_fraction."
+                critical_loads_kw = nothing
+            end
+            if critical_load_fraction != 1.0
+                @warn "ElectricLoad critical_load_fraction must be 1.0 (100%) for off-grid scenarios. Any other value will be overriden when `off_grid_flag` is true. If you wish to alter the load profile or load met, adjust the loads_kw or min_load_met_annual_fraction."
+                critical_load_fraction = 1.0
+            end
         end
 
         if !(off_grid_flag)

src/core/financial.jl

@@ -56,7 +56,7 @@ struct Financial
     owner_tax_rate_fraction::Float64
     owner_discount_rate_fraction::Float64
     analysis_years::Int
-    value_of_lost_load_per_kwh::Union{Array{Float64,1}, Float64}
+    value_of_lost_load_per_kwh::Union{Array{<:Real,1}, Real}
     microgrid_upgrade_cost_fraction::Float64
     macrs_five_year::Array{Float64,1}
     macrs_seven_year::Array{Float64,1}

src/core/pv.jl

@@ -13,7 +13,7 @@
     location::String="both", # one of ["roof", "ground", "both"]
     existing_kw::Real=0,
     min_kw::Real=0,
-    max_kw::Real=1.0e9, # max new capacity (beyond existing_kw)
+    max_kw::Real=1.0e9, # max new DC capacity (beyond existing_kw)
     installed_cost_per_kw::Real=1790.0,
     om_cost_per_kw::Real=18.0,
     degradation_fraction::Real=0.005,