Updated Default PV tilt angles

[bpulluta]

Update on Default PV Tilt Angles

We're excited to share an important update to the default settings for PV tilt angles in the REopt webtool. This update aims to align more closely with PVWatts in determining the optimal PV tilt angle for fixed PV arrays to ensure consistency in our energy modeling. Here’s what’s changed:

Default Tilt Angles for Solar Arrays

Roof and Ground-Mounted Fixed Arrays

• Before: The default tilt angle was set at 10 degrees for rooftop systems and 20 degrees for ground-mounted fixed systems.
• Now: Both rooftop and ground-mounted fixed arrays will default to a tilt angle of 20 degrees, aligning with PVWatts' standard defaults.

One-Axis Tracking Systems

• Before and Now (no change): The tilt angle remains at 0 degrees, maintaining the setup for optimal tracking throughout the year.

Rationale Behind the Change

The decision to adjust the tilt to a fixed 20 degrees for both rooftop and ground installations considers both alignment in energy modeling across the various NREL techno-economic modeling tools and the balance necessary between maximizing energy yield and minimizing the costs and risks associated with installation hardware, particularly in terms of exposure to wind and debris accumulation.

For more detailed information on how these changes affect system performance and other modifications in the tool, please refer to the REopt webtool documentation and check out the updates in the REopt.jl CHANGELOG.