Frequently Asked Questions

Glare Analyses

No - independent research by a national laboratory determined that photovoltaic modules can reflect more than 60% of incoming sunlight at certain times of day. The reflectivity of a material is not constant - it depends on the material's properties and other optical parameters, including the angle of incoming light.

For example, the claim that PV arrays only reflect 5% of light assumes that the modules directly face the sun. Panels lying flat can actually reflect 10x as much at times near sunrise and sunset.

For a deeper dive into the details of solar PV glare, see the Help page.

ForgeSolar is a licensed implementation of analysis software designed by a national laboratory to quantify and understand potential solar glare hazards for pilots, motorists, and other observers.

Analysis results may exhibit some variance between runs due to the analytical simulation method modeling outgoing glare conical emanations. Since it's inception, the SGHAT/ForgeSolar methodology has utilized an analytical approach which balances speed with accuracy, to deliver qualitative results in a timely fashion. If a more rigorous outcome is required, such as quantitative minute-by-minute (or sub-minute) resolution, a custom ray-tracing methodology should be used.

The Version 2 methodology enhancements included in the 2021A update substantially reduce this variance in most cases.

The PV component is designed to simulate PV module reflections. The Vertical Surface component can be used to simulate reflections from a vertical surface, such as a glass building.

The PV component can approximate other materials as a workaround because the underlying methodology uses an analytical approach and does not rigorously simulate the geometry of PV modules, including blocking and shading. The total reflectivity and slope error can be altered to mimic reflection and scattering from different materials. For example, a metal roof could be modeled with a slope error around 100 mrad. Solar reflectance values based on the material and surface finish could be determined from external sources.

Glint and glare differ only in duration. For example, a source of reflection would appear as glint to a motorist driving by, whereas it would appear as glare to a stationary observer viewing it for a longer period of time.
The ocular impact of glare depends on both the incoming irradiance and the angle subtended by the glare source (i.e. size of visible glare spot). Photographs of glare may not adequately reflect these properties; samples of both green glare and yellow glare may appear identical, depending on the camera settings used.

A realistic comparison of yellow glare is the direct viewing of a brief camera flash. The camera flash "sticks" in one's vision temporarily. Similarly, yellow glare is defined as a source with potential to cause a temporary after-image. Conversely, green glare has low potential to cause an after-image.

Subscriptions & Licensing

Due to the complexity and feature changes of the update, prior projects have been set to inactive and can no longer be modified. As a courtesy, projects which were recently active have a grace period of two weeks before they're set to inactive.

New projects can be created with project credits. Credits are provided to Professional and Enterprise users each billing period. Additional project credits can also be purchased as add-ons.

The updated pricing and licensing structure is now project-based to better match the typical workflow. Whereas the old licensing determined the quantity of analyses available per month, the new structure allocates non-expiring project credits and add-ons which can be used as needed. Furthermore, analysis and optimization limits are now set per-project instead of per-month.

These pricing and benefit changes have been designed to balance the growing usage demands and requirements of the ForgeSolar toolset with its long-term viability.

The 2021A Update changed the subscription and licensing structure. Whereas prior licenses determined monthly analysis usage, the new structure is project-based, with higher tiers providing project credits.

The Professional subscription provides 1 Basic project credit each monthly period. If this project tier is insufficient for your needs, consider upgrading to an Enterprise subscription to receive 1 Advanced project credit in future billing periods.

To upgrade an existing Basic project to Advanced, purchase a Project Upgrade add-on.

Full data access is now provided with an active subscription. The new Data Access tier provides project "view" access at a reduced price. To purchase a subscription, please visit the Account Subscription page.

About Us

ForgeSolar includes GlareGauge, the leading solar glare analysis tool used globally every day. ForgeSolar is based on the Solar Glare Hazard Analysis Tool ("SGHAT") licensed from Sandia National Laboratories. Our tools meet the FAA standards for glare analysis.

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Contact Info

6077 Far Hills Ave. #101,
Centerville, Ohio 45459