Features/add min max runtimes

[ckaldemeyer]

This adds the possibility to add min and max runtimes for solph.NonConvexFlows.

See oemof/oemof-examples#16 for two example usages!

[ckaldemeyer]

Memo:

• Write constraint test
• Add equations
• Remove if statements if m.flows[i, o].nonconvex.minimum_downtime is not None from rules
• Adapt release notes
• Allow for time-varying start-/shutdown costs e.g. due to varying resource prices

[ckaldemeyer]

Memo:

Write constraint test
Add equations
Remove if statements if m.flows[i, o].nonconvex.minimum_downtime is not None from rules
Adapt release notes
Allow for time-varying start-/shutdown costs e.g. due to varying resource prices

I have now realized except for the constraint test. If it has been added, it should be fine!

[ckaldemeyer]

@uvchik
add constraint test

Looks good!

[ckaldemeyer]

I would like to have this in the next release so could you also review @simnh and @jnnr ?

[ckaldemeyer]

I would like to have this in the next release so could you also review @simnh and @jnnr ?

You could also review the examples as they illustrate the functionality: oemof/oemof-examples#16

[jnnr]

Good feature! I reviewed the examples, see PR #16. The actual code seems to have a problem passing the tests. There is an error in constraint_tests.py in test_emission_constraints().

[ckaldemeyer]

The actual code seems to have a problem passing the tests. There is an error in constraint_tests.py in test_emission_constraints().

This is weird. The tests have passed with oemof/oemof@1795b1d and started to fail with oemof/oemof@f2dfb12 although the changes only affected the documentation. And the emission constraints are not related to the runtimes..

[simnh]

I can not review the correctness of this new functionality atm, Source code looks fine. Only thing was the update of docstrings (I pushed it).

@ckaldemeyer: Thanks for adding!!

[uvchik]

This is a pyomo issue. It comes with 5.4.x. Just add pyomo<5.4 to the setup.py.

Then we should open a new issue to find out if it is a bug or an API change.

[ckaldemeyer]

I can not review the correctness of this new functionality atm, Source code looks fine. Only thing was the update of docstrings (I pushed it).

@ckaldemeyer: Thanks for adding!!

Thanks!

[uvchik]

See #448.

[ckaldemeyer]

This is a pyomo issue. It comes with 5.4.x. Just add pyomo<5.4 to the setup.py.

Then we should open a new issue to find out if it is a bug or an API change.

Thanks for pointing this out. Nevertheless, this PR should be mergeable now as @simnh @jnnr and you are fine with it and the Pyomo error is of general nature. @jnnr : Feel free to merge if you are o.k. with my changes!

[uvchik]

Okay, I limited the pyomo version to pyomo < 5.4 until we know what happened there.

Now the tests are fine 😄

[jnnr]

Very good. Thanks!