Compliant Converter

API changes

• The component Transformer is renamed to Converter.
  When people hear "transformer", they think of electrical devices.
  However, the Transformer is neither meant to be (only) electrical
  nor bidirectional (as electrical transformers typically are).
  Thus, the more generic term "converter" is now used.
  (Note that we always had the argument "conversion_factor".)
• Unify API for constant sized objects and sizing of investment. For both, Flow and
  GenericStorage, the argument investment is now deprecated. Instead,
  nominal_value and nominal_storage_capacity accept an Investment object.
• Change investment for experimental :class:oemof.solph.components.experimental._sink_dsm.SinkDSM: Remove
  obsolete parameters flex_share_down and flex_share_up.
• Mainline link component :class:oemof.solph.components._link.Link from experimental.

New features

• Add option to run multi-period (dynamic) investment models with oemof.solph as an experimental feature:
  • You can change from standard model to multi-period model by defining the newly introduced periods
    attribute of your energy system. Be aware that it is experimental as of now. periods is a dictionary
    mapping the periods you want to model (usually years) to pandas.date_range objects.
  • Add attributes periods to :class:oemof.solph._energy_system.EnergySystem.
  • Introduce new Pyomo Sets PERIODS and TIMEINDEX in :class:oemof.solph.models.Model.
  • Index all investment-related variables with PERIODS and flow variable with TIMEINDEX, which
    is a tuple of periods and timesteps.
  • Add lifetime tracking for investment options by introducing the attributes lifetime and age.
  • Add new investment-related variables total holding the total capacity, old holding capacity
    to be decommissioned, old_exo (for exogenous) holding existing capacity to be decommissioned and
    old_end holding model-endogenously installed capacity to be decommissioned after its lifetime.
  • Include discounting and calculating annuities in the objective function terms. Introduce attribute discount_rate
    of :class:oemof.solph.models.Model and interest_rate for individual investment objects (options.Investment).
• Add storage_level_constraint that allows to set flows from/to storage (in)active based on storage content.
• Model now accepts a list of EnergySystem objects, which allows for modelling of cellular energysystems.

Documentation

• See extensive documentation in user guide and API reference for the new (experimental) multi-period feature.
• Be more strict about about oemof (meta package) oemof.solph (this package).
• Improved presentation of examples as part of the documentation.

Bug fixes

• Fixed error when calling oemof_installation_test as console script.
• Corrected several typos in the docs.
• Periods with multiple period lengths are now supported in multi-period investment.
• Add missing 'custom_attributes' for the link component

Testing

• Add tests for experimental SinkDSM component.
• Add tests for multi-period investment.

Contributors

• Johannes Kochems
• Patrik Schönfeldt
• Tobi Rohrer
• Julian Endres
• Jann Launer
• Lennart Schürmann