Note
You can download this example as a Jupyter notebook or start it in interactive mode.
Multi-Link usage: CHP with fixed heat-power ratio
This notebook if a demonstration of Link with multiple outputs: Combined-Heat-and-Power (CHP) with fixed heat-power ratio
For a CHP with a more complicated heat-power feasible operational area, see the power-to-gas example
This example demonstrates a Link component with more than one bus output (“bus2” in this case). In general links can have many output buses.
In this example a CHP must be heat-following because there is no other supply of heat to the bus “Frankfurt heat”.
[1]:
import pypsa, numpy as np
---------------------------------------------------------------------------
ValueError Traceback (most recent call last)
Cell In [1], line 1
----> 1 import pypsa, numpy as np
File ~/checkouts/readthedocs.org/user_builds/pypsa/conda/v0.21.2/lib/python3.11/site-packages/pypsa/__init__.py:10
1 # -*- coding: utf-8 -*-
4 """
5 Python for Power Systems Analysis (PyPSA)
6
7 Grid calculation library.
8 """
---> 10 from pypsa import (
11 components,
12 contingency,
13 descriptors,
14 examples,
15 geo,
16 io,
17 linopf,
18 linopt,
19 networkclustering,
20 opf,
21 opt,
22 optimization,
23 pf,
24 plot,
25 )
26 from pypsa.components import Network, SubNetwork
28 __version__ = "0.21.2"
File ~/checkouts/readthedocs.org/user_builds/pypsa/conda/v0.21.2/lib/python3.11/site-packages/pypsa/components.py:50
37 from pypsa.io import (
38 export_to_csv_folder,
39 export_to_hdf5,
(...)
47 import_series_from_dataframe,
48 )
49 from pypsa.opf import network_lopf, network_opf
---> 50 from pypsa.optimization.optimize import OptimizationAccessor
51 from pypsa.pf import (
52 calculate_B_H,
53 calculate_dependent_values,
(...)
62 sub_network_pf,
63 )
64 from pypsa.plot import iplot, plot
File ~/checkouts/readthedocs.org/user_builds/pypsa/conda/v0.21.2/lib/python3.11/site-packages/pypsa/optimization/__init__.py:7
1 #!/usr/bin/env python3
2 # -*- coding: utf-8 -*-
3 """
4 Build optimisation problems from PyPSA networks with Linopy.
5 """
----> 7 from pypsa.optimization import abstract, constraints, optimize, variables
8 from pypsa.optimization.optimize import create_model
File ~/checkouts/readthedocs.org/user_builds/pypsa/conda/v0.21.2/lib/python3.11/site-packages/pypsa/optimization/constraints.py:9
6 import logging
8 import pandas as pd
----> 9 from linopy.expressions import LinearExpression, merge
10 from numpy import arange, cumsum, inf, nan, roll
11 from scipy import sparse
File ~/checkouts/readthedocs.org/user_builds/pypsa/conda/v0.21.2/lib/python3.11/site-packages/linopy/__init__.py:9
1 #!/usr/bin/env python3
2 # -*- coding: utf-8 -*-
3 """
4 Created on Wed Mar 10 11:03:06 2021.
5
6 @author: fabulous
7 """
----> 9 from linopy import model, remote
10 from linopy.expressions import merge
11 from linopy.io import read_netcdf
File ~/checkouts/readthedocs.org/user_builds/pypsa/conda/v0.21.2/lib/python3.11/site-packages/linopy/model.py:22
20 from linopy import solvers
21 from linopy.common import best_int, replace_by_map
---> 22 from linopy.constraints import (
23 AnonymousConstraint,
24 AnonymousScalarConstraint,
25 Constraints,
26 )
27 from linopy.eval import Expr
28 from linopy.expressions import LinearExpression, ScalarLinearExpression
File ~/checkouts/readthedocs.org/user_builds/pypsa/conda/v0.21.2/lib/python3.11/site-packages/linopy/constraints.py:21
18 from scipy.sparse import coo_matrix
19 from xarray import DataArray, Dataset
---> 21 from linopy import expressions, variables
22 from linopy.common import (
23 _merge_inplace,
24 has_assigned_model,
(...)
27 replace_by_map,
28 )
31 class Constraint(DataArray):
File ~/checkouts/readthedocs.org/user_builds/pypsa/conda/v0.21.2/lib/python3.11/site-packages/linopy/expressions.py:23
20 from xarray.core.dataarray import DataArrayCoordinates
21 from xarray.core.groupby import _maybe_reorder, peek_at
---> 23 from linopy import constraints, variables
24 from linopy.common import as_dataarray
27 def exprwrap(method, *default_args, **new_default_kwargs):
File ~/checkouts/readthedocs.org/user_builds/pypsa/conda/v0.21.2/lib/python3.11/site-packages/linopy/variables.py:398
393 roll = varwrap(DataArray.roll)
395 rolling = varwrap(DataArray.rolling)
--> 398 @dataclass(repr=False)
399 class Variables:
400 """
401 A variables container used for storing multiple variable arrays.
402 """
404 labels: Dataset = Dataset()
File ~/checkouts/readthedocs.org/user_builds/pypsa/conda/v0.21.2/lib/python3.11/dataclasses.py:1211, in dataclass.<locals>.wrap(cls)
1210 def wrap(cls):
-> 1211 return _process_class(cls, init, repr, eq, order, unsafe_hash,
1212 frozen, match_args, kw_only, slots,
1213 weakref_slot)
File ~/checkouts/readthedocs.org/user_builds/pypsa/conda/v0.21.2/lib/python3.11/dataclasses.py:959, in _process_class(cls, init, repr, eq, order, unsafe_hash, frozen, match_args, kw_only, slots, weakref_slot)
956 kw_only = True
957 else:
958 # Otherwise it's a field of some type.
--> 959 cls_fields.append(_get_field(cls, name, type, kw_only))
961 for f in cls_fields:
962 fields[f.name] = f
File ~/checkouts/readthedocs.org/user_builds/pypsa/conda/v0.21.2/lib/python3.11/dataclasses.py:816, in _get_field(cls, a_name, a_type, default_kw_only)
812 # For real fields, disallow mutable defaults. Use unhashable as a proxy
813 # indicator for mutability. Read the __hash__ attribute from the class,
814 # not the instance.
815 if f._field_type is _FIELD and f.default.__class__.__hash__ is None:
--> 816 raise ValueError(f'mutable default {type(f.default)} for field '
817 f'{f.name} is not allowed: use default_factory')
819 return f
ValueError: mutable default <class 'xarray.core.dataset.Dataset'> for field labels is not allowed: use default_factory
First tell PyPSA that links will have a 2nd bus by overriding the component_attrs. This can be done for as many buses as you need with format busi for i = 2,3,4,5,….
[2]:
override_component_attrs = pypsa.descriptors.Dict(
{k: v.copy() for k, v in pypsa.components.component_attrs.items()}
)
override_component_attrs["Link"].loc["bus2"] = [
"string",
np.nan,
np.nan,
"2nd bus",
"Input (optional)",
]
override_component_attrs["Link"].loc["efficiency2"] = [
"static or series",
"per unit",
1.0,
"2nd bus efficiency",
"Input (optional)",
]
override_component_attrs["Link"].loc["p2"] = [
"series",
"MW",
0.0,
"2nd bus output",
"Output",
]
---------------------------------------------------------------------------
NameError Traceback (most recent call last)
Cell In [2], line 1
----> 1 override_component_attrs = pypsa.descriptors.Dict(
2 {k: v.copy() for k, v in pypsa.components.component_attrs.items()}
3 )
4 override_component_attrs["Link"].loc["bus2"] = [
5 "string",
6 np.nan,
(...)
9 "Input (optional)",
10 ]
11 override_component_attrs["Link"].loc["efficiency2"] = [
12 "static or series",
13 "per unit",
(...)
16 "Input (optional)",
17 ]
NameError: name 'pypsa' is not defined
[3]:
network = pypsa.Network(override_component_attrs=override_component_attrs)
network.add("Bus", "Frankfurt", carrier="AC")
network.add("Load", "Frankfurt", bus="Frankfurt", p_set=5)
network.add("Bus", "Frankfurt heat", carrier="heat")
network.add("Load", "Frankfurt heat", bus="Frankfurt heat", p_set=3)
network.add("Bus", "Frankfurt gas", carrier="gas")
network.add("Store", "Frankfurt gas", e_initial=1e6, e_nom=1e6, bus="Frankfurt gas")
network.add(
"Link",
"OCGT",
bus0="Frankfurt gas",
bus1="Frankfurt",
p_nom_extendable=True,
capital_cost=600,
efficiency=0.4,
)
network.add(
"Link",
"CHP",
bus0="Frankfurt gas",
bus1="Frankfurt",
bus2="Frankfurt heat",
p_nom_extendable=True,
capital_cost=1400,
efficiency=0.3,
efficiency2=0.3,
)
---------------------------------------------------------------------------
NameError Traceback (most recent call last)
Cell In [3], line 1
----> 1 network = pypsa.Network(override_component_attrs=override_component_attrs)
3 network.add("Bus", "Frankfurt", carrier="AC")
4 network.add("Load", "Frankfurt", bus="Frankfurt", p_set=5)
NameError: name 'pypsa' is not defined
[4]:
network.lopf();
---------------------------------------------------------------------------
NameError Traceback (most recent call last)
Cell In [4], line 1
----> 1 network.lopf();
NameError: name 'network' is not defined
[5]:
network.loads_t.p
---------------------------------------------------------------------------
NameError Traceback (most recent call last)
Cell In [5], line 1
----> 1 network.loads_t.p
NameError: name 'network' is not defined
[6]:
network.links_t.p0
---------------------------------------------------------------------------
NameError Traceback (most recent call last)
Cell In [6], line 1
----> 1 network.links_t.p0
NameError: name 'network' is not defined
[7]:
network.links_t.p1
---------------------------------------------------------------------------
NameError Traceback (most recent call last)
Cell In [7], line 1
----> 1 network.links_t.p1
NameError: name 'network' is not defined
[8]:
network.links_t.p2
---------------------------------------------------------------------------
NameError Traceback (most recent call last)
Cell In [8], line 1
----> 1 network.links_t.p2
NameError: name 'network' is not defined