Aurora Solar

Quick Facts

What is Aurora Solar?

Formal definition

Aurora Solar is a cloud-based software platform for designing, simulating, and selling residential solar PV systems. Combines LIDAR + satellite rooftop modeling, shading analysis, module layout, NREL SAM-driven yield simulation, financial pro forma, customer proposal generation, and permit-pack production.

Engineering definition

Aurora’s Design Mode runs hourly simulations using a modified NREL SAM engine with module manufacturer parameters, LIDAR-derived shading, and time-step shading-corrected I-V curves. Sales Mode uses simplified annual loss factors for speed.

Industry definition

The de facto residential solar design tool in North America. Most US residential installers use Aurora for at least one stage of the design + sales workflow.

Permitting definition

Aurora auto-generates a permit pack including SLD, panel layout, structural analysis (basic), and engineering letter — accepted by many residential AHJs without modification.

Aurora Explained Simply

For installers: Click a house, Aurora auto-detects the roof, you place panels, it gives you a yield estimate, financial proposal, and permit pack — all in 30 minutes.

For homeowners: Your installer is using Aurora to show you a 3D rendering of solar panels on your roof, year-by-year savings, and side-by-side equipment options.

For new engineers: Aurora handles the workflow Helioscope doesn’t — sales presentation, financial modeling, customer-facing proposal. Use the right tool for the stage of the project.

Analogy: Aurora is the “iPhone” of solar design tools — opinionated workflow, polished UX, optimized for the most common residential use case. PVsyst is the “Linux” — more powerful but requires more expertise.

Why Aurora Matters

Sales velocity. Installers using Aurora close at 1.5–2× the rate of installers using static PDF proposals. The interactive customer presentation is the differentiator.

Design quality. LIDAR-driven shading is more accurate than manual obstruction placement.

Speed to permit. Auto-generated permit packs cut residential design-to-permit time from days to hours.

Financial accuracy. Integrated TOU + NEM + storage modeling produces customer-grade financial projections.

Team workflows. Cloud collaboration replaces local CAD file sharing.

How Aurora Works — Workflow

1. Drop pin. Enter the customer address; Aurora pulls LIDAR + satellite imagery.
2. Roof model. Aurora auto-detects roof planes, eaves, and obstructions. Designer refines manually.
3. Obstructions. Add vents, RTUs, skylights, trees with heights from LIDAR.
4. Module layout. Drag-and-drop modules or use auto-fill.
5. Equipment selection. Module, inverter (string/micro/optimizer), battery, monitoring.
6. Shading analysis. Per-module annual shade map.
7. Yield simulation. Sales Mode (fast) or Design Mode (NREL SAM).
8. Financial pro forma. TOU + NEM + battery + incentives.
9. Customer proposal. Interactive web presentation with cost, savings, environmental impact.
10. Permit pack. SLD, layout, panel schedule, structural letter.

Engineering Deep Dive

Sales Mode vs. Design Mode

Sales Mode

• Annual yield from simplified loss factors (typical accuracy ±5–8%).
• Used during initial customer conversation.
• Fast iteration on equipment selection.
• Acceptable for sales proposals but NOT for permit-stage design.

Design Mode

• Hourly simulation via embedded NREL SAM engine.
• Per-module shading and I-V curve modeling.
• Accuracy ±3–5%.
• Required for permit-stage and finance-stage design.

LIDAR rooftop modeling

Aurora uses LIDAR data (USGS 3DEP + private providers) to build a 3D mesh of the roof surface. Accuracy:

• Roof pitch: ±2°.
• Obstruction heights: ±0.3 m.
• Tree shading: ±15% volumetric.
• Coverage: 95%+ of US suburban areas, 70–80% of rural.

Shading model

Voxel-based 3D shading uses sun-path trace from each module’s solar panel position. Computes:

• Annual shade hours per module.
• Per-month shade profile.
• Time-of-day shade correlation.
• Tree growth projection (optional 5-year, 10-year, 25-year scenarios).

NEM 3.0 integration

Aurora’s Financial Engine integrates CPUC’s Avoided Cost Calculator hourly rates. Models:

• Solar-only NBT exports.
• Battery dispatch against import TOU rates.
• SGIP storage rebates.
• 25-year LCOE and IRR.

Design Considerations

• LIDAR coverage gaps. Rural and recently-built areas may have stale LIDAR; manually verify obstructions.
• Tree shading. Use the 5-year growth projection for shading-sensitive designs.
• Module orientation. Aurora’s auto-fill respects roof planes; consider mixing orientations to balance NEM 3.0 export profiles.
• Battery sizing. Use Aurora’s “Self-consumption optimization” mode for NEM 3.0; size for peak-hour offset.
• Permit pack customization. AHJ-specific SLD templates can be uploaded.

Permitting Implications

Aurora’s auto-generated permit pack passes most US residential AHJs without modification. For SolarApp+ AHJs, Aurora outputs SolarApp+-compatible documents. Commercial projects require additional manual drafting.

Utility Interconnection Impact

Aurora-generated reports support utility interconnection applications for residential systems up to typical 11 kW limits. Aurora’s smart inverter selection ensures UL 1741-SB compliance for Rule 21 (CA) and equivalent state interconnection standards.

US Code Requirements

Aurora validates NEC 690.7 (max voltage), basic NEC 690.8 (currents), and inverter listing (UL 1741-SB). Detailed conductor sizing and OCPD selection per NEC 690.9 require manual review.

India Regulatory Context

Aurora is primarily a North American tool; limited adoption in India. Indian residential rooftop projects typically use OpenSolar, SolarLabs, or domestic platforms.

Software Applications — Practical Tips

CRM integration

Aurora integrates with Salesforce, HubSpot, and most solar CRMs for lead-to-proposal handoff.

Multi-mode design

Use Sales Mode for the first customer meeting. Switch to Design Mode for the final proposal and permit submission.

Battery sizing

Aurora’s storage sizing tool runs hourly battery dispatch against the customer’s import/export schedule.

Custom proposals

Templates can be branded with the installer’s logo, color scheme, and value proposition.

Real-World Examples

Residential — 8 kW + 13.5 kWh battery, San Jose

Aurora identified shading from a neighbor’s tree affecting 4 modules. Designer removed those modules and added 2 more on the west roof. Net design boosted year-1 production by 6%. Customer proposal showed $42,000 25-year savings under NEM 3.0.

Residential — 11 kW system, Boston

Aurora auto-detected the steep roof pitch (37°) and adjusted production estimates accordingly. Permit pack generated and submitted to the town in 4 hours from initial site visit.

Residential — 5.4 kW retrofit, San Diego

Existing NEM 2.0 customer adding battery. Aurora modeled the constraint that adding new modules would forfeit NEM 2.0 status; designer optimized battery + existing inverter to maximize self-consumption without expanding PV.

Common Mistakes

1. Using Sales Mode for permit design — accuracy not sufficient.
2. Trusting LIDAR for new construction — recent additions may not be in the LIDAR data.
3. Skipping the manual tree height adjustment — LIDAR can under-estimate tree heights by 10–15%.
4. Not refreshing the Avoided Cost Calculator annually for California projects.
5. Treating auto-SLD as PE-stamped final drawing — needs review for commercial.
6. Forgetting setback rules — Aurora respects published rules but local AHJ may have stricter requirements.

Best Practices

• Pair Aurora (residential design + sales) with PVsyst (commercial/utility bankable yield) for end-to-end project workflows.
• Train sales teams on Sales Mode; designers on Design Mode; engineers on PVsyst export.
• Use Aurora’s customer proposal as a sales contract anchor — interactive, persuasive, easy to revise.
• Update component libraries quarterly for new module/inverter releases.
• Validate auto-generated SLDs against AHJ checklists before submission.

Comparison Tables

Aurora vs. Helioscope vs. OpenSolar

Standards & Certifications

Aurora isn’t itself certified, but it references NEC 690, UL 1741-SB inverter listings, and IEEE 1547-2018 interconnection standards in its design validation.

Key Takeaways

• Aurora Solar is the dominant residential solar design platform in North America — LIDAR rooftop modeling, integrated financials, customer proposals, and permit packs.
• Sales Mode for fast customer conversations; Design Mode for permit-stage engineering with NREL SAM under the hood.
• Best-in-class NEM 3.0 / NBT financial modeling using CPUC’s hourly Avoided Cost Calculator.
• Not bankable for utility-scale — pair with PVsyst for commercial+ projects.
• LIDAR coverage is excellent in US suburban areas but verify manually for new construction and rural sites.