abstract type Policy <: Modification

This is a subtype of Modification that represents a policy to be modeled.

Basic Policy Types are used when defining standard policies in E4ST. They are specified as mods in the config file with a type field.

There are currently six basic policy types. Novel policy types can also be added as needed.

Policies (Policy subtypes)

• ITC
• PTC
• EmissionCap
• EmissionPrice
• RPS
• CES

struct ITC <: Policy

Investment Tax Credit - A tax incentive that is a percentage of capital cost given to generators that meet the qualifications.

Keyword Arguments

• name: policy name
• values: the credit level, stored as an OrderedDict with year and value (:y2020=>0.3). Credit level refers to the percentage of the capex that will be rebated to the investor
• gen_filters: filters for qualifying generators, stored as an OrderedDict with gen table columns and values (:emis_co2=>"<=0.1" for co2 emission rate less than or equal to 0.1)

E4ST.modify_setup_data!(pol::ITC, config, data)

Creates a column in the gen table with the ITC value in each simulation year for the qualifying generators.

ITC values are only calculated when the year is the year_on.

function E4ST.modify_model!(pol::ITC, config, data, model)

Subtracts the ITC price * Capacity in that year from the objective function using add_obj_term!(data, model, PerMWCap(), pol.name, oper = -)

struct ITCStorage <: Policy

Investment Tax Credit - A tax incentive that is a percentage of capital cost given to storage units that meet the qualifications.

Keyword Arguments

• name: policy name
• values: the credit level, stored as an OrderedDict with year and value (:y2020=>0.3). Credit level refers to the percentage of the capex that will be rebated to the investor
• storage_filters: filters for qualifying storage, stored as an OrderedDict with gen table columns and values

E4ST.modify_setup_data!(pol::ITCStorage, config, data)

Creates a column in the gen table with the ITCStorage value in each simulation year for the qualifying generators.

ITCStorage values are calculated based on capex_obj so ITCStorage values only apply in year_on for a generator.

function E4ST.modify_model!(pol::ITCStorage, config, data, model)

Subtracts the ITCStorage price * Capacity in that year from the objective function using add_obj_term!(data, model, PerMWCap(), pol.name, oper = -)

struct PTC <: Policy

Production Tax Credit - A $/MWh tax incentive for the generation of specific technology or under specific conditions.

Keyword Arguments

• name: policy name

• values: $/MWh values of the PTC, stored as an OrderedDict with years and the value (:y2020=>10), note year is a Symbol

• years_after_ref_min: Min (inclusive) number of years the sim year can be after gen reference year (ie. yearon, yearretrofit). If ref year is year_on then this would be equivaled to min gen age.

• years_after_ref_max: Max (inclusive) number of years the sim year can be after gen reference year (ie. yearon, yearretrofit). If ref year is year_on then this would be equivaled to max gen age.

• ref_year_col: Column name to use as reference year for min and max above. Must be a year column. If this is :yearon, then the yearsafterref filters will filter gen age. If this is :yearretrofit, the the yearsafterref filters will filter by time since retrofit.

• gen_filters: filters for qualifying generators, stored as an OrderedDict with gen table columns and values (:emis_co2=>"<=0.1" for co2 emission rate less than or equal to 0.1)

E4ST.modify_setup_data!(pol::PTC, config, data)

Creates a column in the gen table with the PTC value in each simulation year for the qualifying generators.

function E4ST.modify_model!(pol::PTC, config, data, model)

Subtracts the PTC price * generation in that year from the objective function using add_obj_term!(data, model, PerMWhGen(), pol.name, oper = -)

struct GenerationStandard{T} <: Policy

A generation standard (also refered to as a portfolio standard) is a constraint on generation where a portion of generation from certain generators must meet the a portion of the load in a specified region. This encompasses RPSs, CESs, and technology carveouts. To assign the credit (the portion of generation that can contribute) to generators, the Crediting type is used.

• name - Name of the policy
• gen_filters - Filters on which generation qualifies to fulfill the GS. Sometimes qualifying generators may be outside of the GS load region if they supply power to it.
• crediting - the crediting structure and related fields
• load_targets - OrderedDict containing key-value pairs where each key is the name of a requirement (not currently used), and each value is an OrderedDict with the following keys:
  • filters - Filters on which buses fall into the GS load region. The GS will be applied to the load from these buses.
  • targets - The yearly percent targets of the qualifying load that must be covered by the qualifying generation.

modify_setup_data!(pol::GenerationStandard, config, data)

Adds column to the gen table with the credit level of the generation standard. Adds the name and type of the policy to the gspollist in data.

modify_model!(pol::GenerationStandard, config, data, model)

Creates the expression :pgsbus, the load that generation standards are applied to, if it hasn't been created already. Creates a constraint that takes the general form: sum(gs_egen * credit) <= gs_value * sum(gs_load)

abstract type Crediting

Crediting is used to set the credit levels of generators for policies. It is primarily used for GenerationStandards and ReserveRequirements (RPS, CES, carveouts, etc).

Setup inside config yaml

Crediting is specified in the yaml file. A type key must be specified, along with the approriate keys for the credit type you specified. Two examples are shown in the config below.

base_out_path:    "../out/3bus_rps"
mods:
  example_rps:
    type: "RPS"
    crediting: 
      type: "StandardRPSCrediting"
    gen_filters:
      bus_nation: "archenland"
    load_targets:
      stormness_rps:
        filters:
          state: stormness
        targets:
          y2035: 0.85
          y2040: 0.9
  example_rps_gentype:
    type: "RPS"
    crediting: 
      type: "CreditByGentype"
      credits:
        solar: 0.8
        wind: 1.0
        oswind: 1.0
    gen_filters:
      bus_nation: "narnia"
    load_targets:
      narnia_rps:
        targets:
          y2030: 0.7
          y2035: 0.8
          y2040: 0.9
        filters:  
          nation: "narnia"
  stor:
    type: Storage
    file: "../data/3bus/storage.csv"

Standard Crediting subtypes include:

• CreditByBenchmark
• CreditByGentype

Interfaces Implements

• get_credit(c::Crediting, data, gen_row::DataFrameRow) - gets the appropriate credit level for the generator row for the given Crediting subtype.

get_credit(c::Crediting, data, gen_row::DataFrame) ->

Return the credit value for the given generator and crediting type.

get_credit(c::CreditByGentype, data, gen_row::DataFrameRow)

Returns the credit level specified for the gentype in c.credits. If no credit is specified for that gentype, it defaults to 0.

get_credit(c::CreditByBenchmark, data, gen_row::DataFrameRow) ->

Returns the credit level based on the formula max(1.0 - (gen_row[gen_col] / c.benchmark), 0.0).

struct StandardRPSCrediting <: Crediting

Standard RPS crediting structure. Anything included in the RPS gentypes recieves a credit of 1. Creates a CreditByGentype

["solar", "dist_solar", "wind", "oswind", "geothermal", "hcc_new", "hcc_ret"]

CreditByGentype(;credits::OrderedDict{String, Float64})

Crediting method where credit levels are specified by gentypes.

CreditByBenchmark(;gen_col, benchmark)

Awards credit of each generator based on how that generator's gen_col compares to benchmark, using the following formula.

max(1.0 - (gen_row[gen_col] / benchmark), 0.0)

• gen_col::Symbol - the column of the gen table to compare against
• benchmark::Float64 - the benchmark rate to compare with, in the same units as the gen_col.

AvailabilityFactorCrediting <: Crediting

Returns the availability factor of the generator.

struct StandardStorageReserveCrediting <: Crediting

Awards crediting to storage facilities based on their discharge duration and capacity. The values were retrieved from NYISO at the following website, page 31:

https://www.nyiso.com/documents/20142/23590734/20210805%20NYISO%20-%20Capacity%20Accreditation%20Current%20Rules%20Final.pdf

const CES = GenerationStandard{:CES}

Clean Energy Standard - A policy in which the load serving entity must purchase a certain ampount of clean energy credits. The number of credits for a type of generation typically depends on it's emission rates relative to a benchmark.

CES is defined as an alias of GenerationStandard.

No default crediting is specified although the standard crediting will be CreditByBenchmark where the benchmark should be specified in the config.

Fields

• name - Name of the policy
• targets - The yearly targets for the CES
• crediting - the crediting structure and related fields. CES crediting is often CreditByBenchmark.
• gen_filters - Filters on which generation qualifies to fulfill the CES. Sometimes qualifying generators may be outside of the RPS load region if they supply power to it.
• load_bus_filters - Filters on which buses fall into the load region. The CES will be applied to the load from these buses.

GenerationStandard

const RPS = GenerationStandard{:RPS}

Renewable Portfolio Standard - A policy that constrains a certain amount of load from a region to be supplied by qualifying clean/renewable energy.

RPS is defined as an alias of GenerationStandard where the default crediting type is StandardRPSCrediting. mod_rank for RPS will be 1.0 because that is the rank of GenerationStandards

Fields

• name - Name of the policy
• targets - The yearly targets for the RPS
• crediting - the crediting structure and related fields. Standard CES crediting is CreditingByBenchmark.
• gen_filters - Filters on which generation qualifies to fulfill the RPS. Sometimes qualifying generators may be outside of the RPS load region if they supply power to it.
• load_bus_filters - Filters on which buses fall into the RPS load region. The RPS will be applied to the load from these buses.

GenerationStandard

struct GenerationConstraint <: Modification

Generation Constraint - A Modification that applies a constraint based on (yearly generation) * (a column from the gen table).

• name: modification name
• col: gen table column
• max_values: maximum values for a year (defaults as an empty OrderedDict if no maxs)
• min_values: minimum values for a year (defaults as an empty OrderedDict if no mins)
• gen_filters: OrderedDict of the generator filters

modify_model!(cons::GenerationConstraint, config, data, model)

Creates upper and lower bound constraints on the generators. See also GenerationConstraint for more details

struct EmissionCap <: Policy

Emission Cap - A limit on a certain emission for a given set of generators.

• name: name of the policy (Symbol)
• emis_col: name of the emission rate column in the gen table (ie. emis_co2) (Symbol)
• targets: OrderedDict of cap targets by year
• gen_filters: OrderedDict of generator filters
• gen_cons: GenerationConstraint Modification created on instantiation of the EmissionCap (not specified in config). It sets the cap targets as the max_targets of the GenerationConstraint and passes on other fields.

E4ST.modify_model!(pol::EmissionCap, config, data, model)

Calls modify_model!(cons::GenerationConstraint, config, data, model)

struct EmissionPrice <: Policy

Emission Price - A price on a certain emission for a given set of generators.

• name: name of the policy (Symbol)
• emis_col: name of the emission rate column in the gen table (ie. emis_co2) (Symbol)
• prices: OrderedDict of prices by year. Given as price per unit of emissions (ie. $/short ton)
• years_after_ref_min: Min (inclusive) number of years the sim year can be after gen reference year (ie. yearon, yearretrofit). If ref year is year_on then this would be equivaled to min gen age. This is rarely used in real policy, so be careful if changing from default value
• years_after_ref_max: Max (inclusive) number of years the sim year can be after gen reference year (ie. yearon, yearretrofit). If ref year is year_on then this would be equivaled to max gen age. This is rarely used in real policy, so be careful if changing from default value
• ref_year_col: Column name to use as reference year for min and max above. Must be a year column. If this is :yearon, then the yearsafterref filters will filter gen age. If this is :yearretrofit, the the yearsafterref filters will filter by time since retrofit. This is rarely used in real policy, so be careful if changing from default value
• gen_filters: OrderedDict of generator filters
• hour_filters: OrderedDict of hour filters

E4ST.modify_model!(pol::EmissionPrice, config, data, model)

Adds a column to the gen table containing the emission price as a per MWh value (gen emission rate * emission price). Adds this as a PerMWhGen price to the objective function using add_obj_term!