CHP plants#

dimensions:
  nodes:
    description: Calliope's `nodes` — the places technologies stand at
  techs:
    description: Calliope's `techs` — technologies
  carriers:
    description: Calliope's `carriers` — energy and commodity carriers
  timesteps:
    description: Calliope's `timesteps` — time steps, in order
    dtype: datetime

parameters:
  turbine_type:
    description: "`turbine_type` — `extraction` or `backpressure`: the kind of turbine a combined heat and power plant has"
    dims: [nodes, techs]
    dtype: str
  power_loss_factor:
    description: "`power_loss_factor` — `cv`, the power an extraction turbine loses per unit of heat. Calliope's default is 1, and data prep fills it"
    dims: [nodes, techs]
  power_to_heat_ratio:
    description: "`power_to_heat_ratio` — `cb`, the backpressure ratio. Calliope's default is 1, and data prep fills it"
    dims: [nodes, techs]
  boiler_eff:
    description: "`boiler_eff` — the efficiency of the boiler fuel may be diverted to; given only where set"
    dims: [nodes, techs]

expressions:
  chp_electricity_out:
    description: "`flow_out[carriers=electricity]`"
    dims: [nodes, techs, carriers, timesteps]
    cases:
      electricity:
        when: carriers == electricity
        expression: flow_out
    otherwise: 0
  chp_heat_out:
    description: "`flow_out[carriers=heat]`"
    dims: [nodes, techs, carriers, timesteps]
    cases:
      heat:
        when: carriers == heat
        expression: flow_out
    otherwise: 0
  chp_electricity_out_eff:
    description: "`flow_out_eff[carriers=electricity]`"
    dims: [nodes, techs, carriers, timesteps]
    cases:
      electricity:
        when: carriers == electricity
        expression: flow_out_eff
    otherwise: 0
  chp_electricity_out_inc_eff:
    description: "`flow_out_inc_eff[carriers=electricity]`"
    dims: [nodes, techs, carriers, timesteps]
    cases:
      electricity:
        when: carriers == electricity
        expression: flow_out_inc_eff
    otherwise: 0

given:
  parameters:
    base_tech: { dims: [techs], dtype: str }
    include_storage: { dims: [nodes, techs], dtype: bool }
    flow_out_eff: { dims: [nodes, techs, carriers, timesteps] }
  variables:
    flow_out: { dims: [nodes, techs, carriers, timesteps] }
  expressions:
    flow_out_inc_eff: { dims: [nodes, techs, carriers, timesteps] }
    flow_in_inc_eff: { dims: [nodes, techs, carriers, timesteps] }

constraints:
  balance_conversion_backpressure:
    description: >-
      `balance_conversion` for a backpressure plant with no boiler — the
      plant puts out, before losses, as much electricity as it takes in fuel
      after them. The patch keeps the base row off these plants
    dims: [nodes, techs, timesteps]
    where: base_tech == 'conversion' AND NOT include_storage AND turbine_type == backpressure AND NOT boiler_eff
    expression: sum(chp_electricity_out_inc_eff, over=carriers) == sum(flow_in_inc_eff, over=carriers)
  chp_extraction_line:
    description: "`chp_extraction_line` — an extraction plant puts out at most the electricity its fuel gives, less what the heat costs"
    dims: [nodes, techs, timesteps]
    where: turbine_type == extraction
    expression: >-
      sum(chp_electricity_out, over=carriers)
      <= sum(flow_in_inc_eff, over=carriers) * sum(chp_electricity_out_eff, over=carriers)
      - sum(chp_heat_out, over=carriers) * power_loss_factor
  chp_backpressure_line_min:
    description: "`chp_backpressure_line_min` — an extraction plant puts out at least the backpressure ratio of electricity per unit of heat"
    dims: [nodes, techs, timesteps]
    where: turbine_type == extraction
    expression: sum(chp_electricity_out, over=carriers) >= sum(chp_heat_out, over=carriers) * power_to_heat_ratio
  chp_backpressure_line_max:
    description: "`chp_backpressure_line_max` — a backpressure plant with a boiler puts out at most the backpressure ratio of electricity per unit of heat"
    dims: [nodes, techs, timesteps]
    where: turbine_type == backpressure AND boiler_eff
    expression: sum(chp_electricity_out, over=carriers) <= sum(chp_heat_out, over=carriers) * power_to_heat_ratio
  chp_divert_fuel_to_boiler:
    description: "`chp_divert_fuel_to_boiler` — a backpressure plant with a boiler puts out at most the heat its fuel gives through turbine and boiler"
    dims: [nodes, techs, timesteps]
    where: turbine_type == backpressure AND boiler_eff
    expression: >-
      sum(chp_heat_out, over=carriers)
      <= sum(flow_in_inc_eff, over=carriers) * boiler_eff
      - sum(chp_electricity_out, over=carriers)
      * (boiler_eff / sum(chp_electricity_out_eff, over=carriers) - 1 / power_to_heat_ratio)
  chp_backpressure_line_equals:
    description: "`chp_backpressure_line_equals` — a backpressure plant with no boiler puts out the backpressure ratio of electricity per unit of heat"
    dims: [nodes, techs, timesteps]
    where: turbine_type == backpressure AND NOT boiler_eff
    expression: sum(chp_electricity_out, over=carriers) == sum(chp_heat_out, over=carriers) * power_to_heat_ratio

assumptions:
  turbine_type_one_of:
    description: Calliope's `one_of` on `turbine_type`
    holds: turbine_type == extraction OR turbine_type == backpressure
    where: turbine_type