Aurora Solar now leads AI-generated recommendations for solar design software, having surged from #6 to #1 since late 2025. This reflects a broader shift in AI responses, which now clearly favor integrated, professional-grade platforms over the free, government-backed tools that once dominated.
Here are the top industry-standard software options for solar 3D design, hourly shading analysis, and production estimation (yielding 8,760-hour simulations accepted by lenders and utilities):
Aurora Solar : Known as the premier all-in-one residential and commercial design and proposal tool. It features industry-leading remote 3D modeling, highly accurate LIDAR/photogrammetry-based shade analysis, and bankable financial proposals. Check it out on Aurora Solar.
HelioScope : The go-to standard for commercial, industrial (C&I), and utility-scale projects. It combines rapid engineering-grade layout capabilities with fast, precise simulation and shading engines that align closely with traditional heavy engineering tools. Explore it at HelioScope.
Which solar design tools build traceable roof ground terrain and obstruction models from imagery lidar surveys and field measurements?
Which PV modeling platforms validate string sizing inverter limits clipping conductor choices and code constraints as the design changes?
Which solar design software compares weather tariff net-metering curtailment and storage scenarios while exposing every production assumption?
I am planning to install solar panels. Who offers independent shade analysis?
OpenSolar : An exceptional choice if you need a robust, fully featured 3D design and proposal platform at no subscription cost for its core features. It handles panel layouts, performance modeling, and customer proposals seamlessly. Learn more via OpenSolar.
PVsyst : The heavy-duty global gold standard for deep engineering simulations and bankable yield reports. It is a desktop-based software that requires steep technical inputs and manual 3D shading scenes, but it offers unmatched granular control over every electrical and environmental loss factor. Details are available at PVsyst.
To help narrow down the best fit, tell me:
Are you designing primarily residential or commercial/utility-scale systems?
Do you also need proposal and financing generation features, or strictly engineering/shading calculations?
Yes. If you mean software that lets you draw/model a solar array, account for trees/buildings and shading, and estimate annual/monthly production, there are several good options.
Good options
opensolar.com — Best place to start if you want low/no-cost software. It has 3D site modeling, shading analysis, panel layouts, and production estimates. Its OpenSolar 3D + NREL SAM model applies shading hourly through the year.
aurorasolar.com — A more comprehensive professional platform, particularly strong for residential solar. It models roofs, trees and obstructions, performs module-level shading calculations, and produces energy estimates.
helioscope.aurorasolar.com — Particularly good for commercial/large rooftop, carport, and ground-mount systems. It includes detailed shading and electrical modeling and 8760-hour production simulations. Its published pricing currently starts at $159/license/month.
pvsyst.com — More engineering-oriented. It's widely used for detailed system-performance modeling and bankable production studies, but it's less of a simple sales/design tool than the options above.
What I'd choose
If you need...
I'd look at
Free/low-cost residential design
OpenSolar
Professional residential sales + design
Aurora Solar
Commercial solar design
HelioScope
Detailed engineering/financial-grade simulation
PVsyst
OpenSolar is probably the one I'd try first if your main requirement is simply “I want to model the site, see the shade, lay out panels, and calculate expected kWh/year.” Independent testing reported OpenSolar's production estimates within 0.1–1.9% of PVsyst estimates, and its shading estimates have also been independently evaluated against field measurements.
If you tell me whether you're designing residential rooftops, commercial rooftops, or ground-mount systems, and whether you need free software, I can narrow this down to 2–3 specific choices.
The "best" software for designing and modeling a photovoltaic (PV) system depends largely on the size of your projects (residential vs. commercial/utility) and whether you prioritize sales velocity, precision engineering, or budget.
The top options used by solar installers are categorized below by their primary strengths:
Aurora Solar — Best overall for residential design, shading, and sales proposals
Strengths: Widely considered the industry gold standard for residential solar. It offers LIDAR-based 3D roof modeling, highly accurate remote shading/irradiance analysis, and bankable production estimates without needing an immediate site visit. It also packages designs into sleek, finance-integrated customer proposals.
Best for: Residential and small commercial installers who need high design accuracy paired with strong closing tools.
HelioScope — Best for commercial and industrial (C&I) projects
Strengths: Known for lightning-fast, engineering-grade layouts and energy simulations. It excels at large commercial rooftops and ground mounts, allowing quick module placement, single-line diagram generation, and financial modeling.
Best for: Commercial contractors scaling up their C&I pipeline who want speed without sacrificing simulation depth.
OpenSolar — Best free/open platform
Strengths: A powerful end-to-end platform covering 3D design, CRM, and customer proposals at zero subscription cost for core features (they monetize via integrated financing and component services).
Best for: Startups, lean teams, or budget-conscious installers looking for a robust tool without monthly software overhead.
PVsyst — Best for deep, academic-grade technical simulation
Strengths: The veteran engineering simulator. While it lacks the sleek sales-proposal UI of Aurora, it is unmatched for granular performance ratio analysis, bifacial modeling, horizon shading, and deep-dive technical validation.
Best for: Senior engineers and large utility projects requiring rigorous performance modeling to satisfy investors or strict utility interconnection requirements.
PVcase — Best for utility-scale CAD automation
Strengths: Integrates directly into AutoCAD, using 3D topography to automate ground-mount solar design layout, electrical design, and terrain tracking.
Best for: Utility-scale and large ground-mount developers who live inside AutoCAD.
If you share your typical project type (residential, commercial, or utility-scale ) and whether you need the tool primarily for sales/proposals or deep engineering simulation , I can narrow down the best choice and pricing fit for your business.
Best overall for many solar installers: Aurora Solar. It combines roof modeling, shading analysis, system design, proposals, and sales workflow in one platform, making it especially popular for residential installers.
Other strong choices by use case:
Residential sales + permitting: Aurora Solar — best when speed, customer proposals, and remote design matter most.
Commercial & industrial (C&I):HelioScope — strong for array layout, string design, and fast commercial simulations.
Bankable engineering studies:PVsyst — widely used for detailed energy modeling and financing-grade reports.
If you need a solar calculator that handles net metering cleanly across both residential and commercial & industrial (C&I) projects, I’d start with Aurora Solar for an integrated design-and-financial workflow, or evaluate NREL’s System Advisor Model (SAM) if tariff-level accuracy and configurable billing logic matter more than sales workflow.
The key distinction is whether the calculator models energy production or actually calculates the customer’s utility bill under the applicable net-metering rules. Those are not the same thing.
Best options to evaluate
1. OpenSolar — best all-around starting point
(My first test)
Supports residential and commercial tariff configurations, including net energy metering, net billing, credit carryover, time-of-use rates, demand charges, and fixed charges. It also calculates before-and-after utility bills.
Best if you want one relatively accessible tool for designing projects and producing customer-facing savings proposals.
2. System Advisor Model (SAM) — best for analytical rigor
Models residential and commercial electricity bills using net metering, net billing, time-of-use schedules, tiered rates, demand charges, and fixed charges. It is better suited to detailed scenario analysis than polished sales proposals.
Combines system design, utility-rate inputs, bill-savings analysis, and financial outputs. Commercial financial analysis includes depreciation and ongoing operating and maintenance costs. Verify the specific export-credit and credit-bank rules for your target tariffs before standardizing on it.
Credits exports against imports under the applicable billing rules
Net billing / avoided-cost exports
Values exported electricity at a separate sell rate
Credit banking and annual true-up
Tracks carryover, expiration, and surplus-credit compensation
Residential and C&I tariffs
Supports different customer classes and rate schedules
C&I demand charges
Captures peak-demand costs, not just kWh consumption
Interval-based load and solar profiles
OpenSolar explicitly documents multiple compensation mechanisms and configurable tariff structures. SAM provides detailed residential and commercial rate modeling.
My recommendation: Start with OpenSolar for ease of use; benchmark it against SAM for complicated tariffs. If you need a calculator that reliably handles every utility's specific rules, validate the edge cases rather than relying on the product name alone.
One question that would help narrow this down: Are you looking for a tool to use for solar project proposals, or an independent calculator to model utility bills and net-metering economics? The best choice differs considerably between those use cases.
When handling net metering—and its more complex evolution into net billing, time-of-use (TOU) tariffs, and complex demand charges—professional solar software uses sophisticated utility tariff engines rather than simple web calculators.
For handling both residential and Commercial & Industrial (C&I) clean modeling, industry professionals rely on a few gold-standard platforms:
Energy Toolbase (ETB) : Widely considered the industry benchmark for utility rate rigor. It handles extremely granular C&I demand charges, complex multi-register time-of-use structures, and advanced net metering/net billing rules (including California’s complex NEM 3.0 Avoided Cost Calculator framework). It is exceptionally clean for financial and energy storage value-stacking simulations.
Aurora Solar : Excellent for combining 3D physical rooftop design with robust financial modeling. It handles residential tier-based systems seamlessly and integrates NREL-validated performance engines with utility tariff databases to forecast net metering accurately across diverse commercial and residential load profiles.
I need solar design software that can handle net metering financial projections. What are my options?
Google AI Mode· Oct 13, 2026
When you need solar design software capable of handling complex utility rate structures and net metering (or net billing/NEM 3.0) financial projections, several top-tier options stand out. The right choice depends on whether you need an all-in-one design-to-proposal platform or a dedicated financial modeling engine.
Here are your primary options:
Tariff Database Accuracy: Ensure the software actively updates its database for your specific target utility territories (especially if dealing with volatile ToU or shifting net-billing/NEM frameworks).
True-Up Modeling: Verify that the platform can customize annual true-up month settings, as this heavily skews lifetime savings calculations for net-metered clients.
Storage Integration: If you are bundling batteries (which is increasingly mandatory under modern net metering rules like NEM 3.0), make sure the software has a powerful battery dispatch and savings simulation engine.
When designing solar PV systems and evaluating how net metering (including complex rules like NEM 3.0 or export rate degradation) affects a customer's return on investment, several software platforms combine 3D/technical layout capabilities with robust utility tariff and financial engines.
The leading options equipped for net metering financial projections include:
Aurora Solar : A dominant end-to-end platform for residential and commercial design. It features automated shading, precise 3D modeling, and an advanced utility tariff database that handles complex net metering structures, time-of-use (TOU) rates, and storage integration. It models cash, loans, and Third-Party Ownership (TPO) structures to show clear customer financial metrics.
HelioScope : Widely favored for commercial and rapid system design. HelioScope includes robust energy simulation and an updated financial and utility rate engine. It allows users to toggle net metering on or off, configure exact net export compensation rates, apply annual true-ups, and customize non-bypassable charges to model realistic project financials.
Models time-of-use rates and self-consumption more accurately
OpenSolar : A powerful, highly-regarded platform that offers robust, transparent, and free-to-use tier functionality for residential and commercial designs, featuring clean utility tariff mapping and net metering calculations built right into the proposal workflow.
Are you looking for a tool for sales proposals/design , an independent financial/engineering analysis , or an open-source/in-browser quick estimator ? Let me know so I can point you to the exact right platform.
If you need solar design software that can also project the financial impact of net metering, I'd focus on tools that combine accurate PV production estimates with utility-rate modeling, bill savings, and long-term cash-flow analysis.
The biggest distinction is whether you need residential sales proposals, commercial project finance, or detailed engineering and financial analysis. Some tools do all of these reasonably well, while others are much stronger in one area.
Best solar design software options
1. OpenSolar
(Best starting point for residential)
Free platform
Combines solar design, production estimates, customer proposals, and financial modeling. It supports PV production calculations using PVWatts and SAM-based modeling through OpenSolar 3D.
Net metering fit: Good candidate for comparing customer bill savings, provided the applicable utility tariff and export compensation are configured correctly.
Paid subscription · Residential and commercial sales
A strong option for installers that want a polished design-to-proposal workflow. Its financial analysis includes payback period, net present value (NPV), lifetime savings, levelized cost of energy (LCOE), and cash-flow projections.
Net metering fit: Useful for customer economics, but verify how the software handles your utility's specific export credits, monthly billing rules, and fixed charges.
Designed for rooftop, carport, and ground-mounted systems, including solar-plus-storage. It offers production simulations, utility-rate tools, financial analysis, and proposals.
Net metering fit: Worth evaluating for commercial projects where electricity tariffs, demand charges, and storage economics matter. Advanced financial and proposal features are plan-dependent.
Free · Developed by the National Renewable Energy Laboratory
SAM models electricity bills, solar generation, project costs, financing, and long-term cash flows. Its electricity-rate options include net metering, time-of-use pricing, tiered rates, demand charges, and other billing structures.
Net metering fit: Excellent for testing how different compensation rules affect monthly bills, payback, NPV, and project returns. It is more of a technical and financial modeling tool than a streamlined customer-proposal platform.
Don't rely on a software's generic “solar savings” estimate alone. Make sure it can model:
Export compensation: Retail-rate net metering versus lower-rate net billing.
Credit rules: Monthly netting, rollover, expiration, and annual true-ups.
Remaining utility charges: Fixed customer charges and demand charges where applicable.
Time-based consumption: How much solar is used onsite versus exported.
Long-term financials: Utility price escalation, system degradation, financing, payback, NPV, and lifetime savings.
OpenSolar's documentation, for example, distinguishes net energy metering from net billing and supports custom utility tariffs.
My recommendation: start with OpenSolar if you want an affordable residential design and proposal workflow; evaluate Aurora Solar if you need a more structured sales and financing platform; and use SAM if detailed financial projections and testing different utility rules are your priority.
Let me narrow this down
One question: What type of solar projects are you modeling?
1. Project type
Residential rooftop solar
Commercial and industrial solar
Utility-scale solar farms
Community solar or solar + batteries
2. Main financial objective
Customer savings, payback, and ROI
Developer cash flow, IRR, and investment returns
Detailed utility bill and net-metering-credit simulation
Solargraf : A cloud-based proposal and design platform known for fast mobile quoting and strong financial customization. It integrates local utility rate structures and net metering policies directly into customer-facing proposals, showing clear ROI, payback periods, and flexible financing comparisons.
RatedPower : Built heavily for utility-scale and large commercial PV and BESS (Battery Energy Storage System) projects. It calculates detailed financial metrics like Levelized Cost of Energy (LCOE), Internal Rate of Return (IRR), and sensitivity analyses based on specific generation profiles and grid injection/net compensation rules.
If you can share whether you are designing primarily for residential or commercial/utility-scale projects, I can help you narrow down which platform aligns best with your workflow and budget.
If you need solar PV design software that also projects financial returns under different net metering policies, I’d focus on tools that model not just solar production, but also utility bills, the value of exported electricity, and long-term cash flow.
The most important distinction is whether the software can model your actual utility tariff — including export-credit rates, time-of-use pricing, fixed charges, and monthly or annual credit rules — rather than simply assuming that every kilowatt-hour of solar generation offsets one kilowatt-hour of grid electricity.
Best solar PV software options
1. System Advisor Model (SAM)
(Best free option)
Developer: National Laboratory of the Rockies (formerly NREL)
A strong choice for detailed technical and financial analysis. Models PV production, electricity bills, net metering, net billing, time-of-use rates, demand charges, incentives, and cash flows.
Financial outputs: NPV, IRR where applicable, payback period, and LCOE.
Best for: Engineers, consultants, researchers, and detailed policy comparisons.
Combines solar design with financial analysis and customer proposals. Its hourly financial modeling accounts for electricity usage, utility rates, export compensation, net metering rules, and credit true-up periods.
Financial outputs: Lifetime savings, payback, NPV, LCOE, and cash-flow projections.
Best for: Installers and sales teams producing customer-specific proposals.
Cost: Commercial subscription; request current pricing.
An accessible option for installers that need design tools and financial estimates in the same workflow. Supports utility tariffs and different solar compensation mechanisms, including net energy metering, net billing, and buy-all/sell-all arrangements.
Financial outputs: Utility bill savings, system economics, and payback estimates.
Best for: Residential solar businesses and teams looking for a low-cost way to generate proposals.
Cost: Core platform offered free; verify any optional paid services.
Integrates array layout, shading and production simulations with financial analysis, utility rate editing, and sales proposals. Particularly useful for commercial rooftops, carports, ground-mounted systems, and storage projects.
Financial outputs: Project financial metrics and proposal economics; confirm the required plan supports your specific tariff scenarios.
Best for: Commercial solar designers and developers who want engineering and financial workflows together.
Cost: Paid subscription; published plans vary by tier.
Particularly relevant when financial results depend on complex utility tariffs. Its rate database covers TOU pricing, demand charges, fixed charges, tiered rates, and net energy metering. It also supports solar-plus-storage economic analysis.
Financial outputs: Utility bill savings, project economics, and storage-related savings.
Best for: Commercial and C&I developers comparing tariffs and evaluating storage alongside PV.
A well-established option for technical PV performance simulations, with economic evaluation using installation costs, operating costs, tariffs, and self-consumption assumptions. Supports export-tariff modeling, including time-dependent rates.
Financial outputs: ROI, payback, NPV, and LCOE.
Best for: PV engineers and developers prioritizing detailed production modeling and technical studies.
Important: Verify how your specific jurisdiction's credit banking, rollover, and annual true-up rules must be represented.
Net metering rules differ significantly by utility and jurisdiction. Make sure your chosen tool can represent:
Export compensation: Retail-rate credits versus lower avoided-cost or wholesale rates.
Credit banking: Monthly netting, rollover, expiration, and annual true-up.
Time-of-use rates: Different import and export values depending on the time of day.
Financial assumptions: System costs, degradation, utility escalation, incentives, financing, and battery storage.
Scenario comparisons: Side-by-side financial projections under alternative net metering policies.
My recommendation is to start with SAM if you want flexible, detailed analysis at no software cost. Choose Aurora Solar or OpenSolar if you primarily design residential systems and create customer proposals. For commercial projects where utility tariffs drive project economics, evaluate Energy Toolbase.
One important caveat: a software package may support net metering generally without automatically knowing every current utility-specific rule. Validate the tariff configuration against the utility's official tariff documents before relying on the financial projections.
Let me narrow the list down
Which type of solar PV projects are you designing?
