Integrate PVGIS optimum tilt

[BenWinchester]

Issue

CLOVER currently requires a user, within their solar_generation_inputs.yaml file, to specify the tilt angle of the panels that they are investigating. For some users, case studies will be investigating rooftops for which the tilt angle is already specified. For the vast majority however, case studies will be looking at installations for which the tilt angles of the panels is yet to be determined, or for which the tilt angle could be optimised as part of their investigation. This group of users currently need to use a non-integrated piece of software, such as PVGIS, to determine the optimum tilt angle for their panels and then use this in their simulations and optimisations.

Proposal

PVGIS offers an API which could be easily integrated with CLOVER to provide a seamless experience for simulating and optimising these locations.

Alternatives include:

• Manually optimising the panel angle within CLOVER based on data from
  • renewables.ninja
  • PVGIS
• Sticking with the existing system of separate calculations for this optimisation.

[BenWinchester]

General thoughts

@hamishbeath , I know you've raised concerns about the accuracy of this calculation that PVGIS does for a specific location. As such, it's probably better to, instead, review the default value and produce a more accurate metric? We could even include, perhaps, a range of default values based on tropic position (Equator to tropic, tropic to 60 degrees, 60 degrees to pole) or something similar?

I don't think it's worth binning this completely, but perhaps shifting the discussion away from using PVGIS and, instead, it forming part of the desire to update the default input values 😃