Software Comparison

Best Solar Design Software in India for 2026

Shashank·Founder·May 11, 2026·10 min read

Last updated August 11, 2026 (Originally published May 11, 2026)

Reslink is the best solar design software for solar EPCs in India in 2026. It is the only platform built specifically for how Indian EPCs work, covering 3D design, shadow simulation, automated BOE, Bills of Structure, bank-ready SLD, CAPEX and OPEX proposals, ALMM compliance, PM Surya Ghar subsidy calculation, and WhatsApp proposal delivery in one connected workflow, in India and every other market it operates in.

Quick Answer

Question	Answer
What is the best solar design software for Indian EPCs?	Reslink, for the complete workflow, design through bank-ready documents. PVsyst remains essential alongside it specifically for utility-scale bankability simulation.
Is this comparison biased since Reslink wrote it?	Yes, and we say so directly rather than pretending otherwise. Judge it on whether the specific, checkable claims hold up, not on who wrote it.
Does one tool win every category?	No. PVsyst wins simulation depth outright, that's not in dispute. Every other criterion, mobile capability, automated BOM, bank-ready documents, India compliance, Reslink covers and the others don't.
What's the single biggest fact?	Of six tools compared, only Reslink covers the complete workflow, mobile-first design, automated BOE and Bills of Structure, bank-ready SLD, local subsidy, native OPEX, and WhatsApp delivery, in any market it operates in, including the US.
What should EPCs do now?	Check which of the five gap areas, mobile, BOM, SLD, ALMM, subsidy, are currently being handled manually, regardless of which tool is in use today.

Choosing solar design software in India is different from choosing it for the US or European market. Indian EPCs operate in a context with compliance requirements and customer expectations that most global platforms were not designed for. Before evaluating specific tools, you need to be clear on which criteria actually matter for your business.

1. India-Specific Compliance Out of the Box

Indian solar projects must navigate PM Surya Ghar subsidy calculations, ALMM-compliant equipment requirements, state-specific DISCOM net metering applications, and BIS earthing standards. MNRE guidelines govern each of these requirements and update periodically. Software that requires manual configuration of these parameters for every project costs your team time and introduces errors. The best tools for Indian EPCs have these parameters built in natively, not bolted on as custom fields.

2. Mobile Design Capability

In the Indian residential and commercial rooftop market, deals are frequently closed in the first meeting. An EPC whose sales rep can model the roof in 3D, run shadow analysis, and deliver a proposal on WhatsApp before leaving the site is structurally advantaged over one who sends a proposal two days later. If your sales team works in the field rather than from an office, mobile design capability is not a convenience, it's a necessity.
See how this works in practice in our guide to how Reslink's 3D solar design works.

3. Automated BOM Generation

Manual BOM preparation in Excel is the most error-prone step in solar EPC execution. A mismatch between the design and the procurement order costs money on every project it occurs. Software that generates the Bills of Electrical (BOE) and Bills of Structure automatically from the 3D design eliminates this failure mode. This is a non-negotiable for EPCs running more than 15 projects per month.

4. Bank-Ready Document Output

For projects requiring debt financing, banks and financial institutions require Single Line Diagrams (SLDs), layout drawings, and string drawings that meet submission standards. Most design tools produce outputs that need post-processing by an engineering consultant before they are bankable. Tools that generate bank-ready documents natively eliminate this step and compress the financing timeline significantly.

5. Scale Coverage

If your business spans residential rooftop and commercial or utility-scale projects, you need a platform that covers the full range without requiring a second tool for larger projects. Switching between platforms for different project sizes creates version mismatches, training overhead, and workflow fragmentation that compounds as project volume grows.

The 6 Tools Compared

1. Reslink

Reslink is a mobile-first solar design and EPC workflow platform built for solar companies that need to move faster from site assessment to final proposal. It works exactly as seamlessly on desktop as it does on mobile, this isn't a stripped-down field version of a desktop tool, EPC teams get the full 3D design workflow, satellite imagery, roof modelling, shadow analysis, panel placement, energy simulation, and proposal automation, on a phone, a tablet, or a desktop, with identical capability.

The platform supports projects from residential rooftops to C&I, open access, and utility-scale ground-mount systems from 3 kW to 1 GW in a single platform. EPC teams can generate client-ready proposals with ROI calculations, payback analysis, generation reports, shadow analysis, CAPEX/OPEX models, and bank-ready documentation, helping them present a stronger technical and financial case during customer conversations.

Reslink also connects design with execution through automated BOE, Bills of Structure, SLD reports, layout drawings, string drawings, BESS simulation, load analysis, and BOM-led planning. This makes Reslink more than a solar design software. It functions as an operating layer for EPCs, connecting design, proposal generation, financial modelling, documentation, procurement planning, and project execution in one platform.

For EPCs, Reslink's core advantage is speed and accessibility. Field sales teams can create solar proposals on the site itself, reducing dependency on back-office design teams and repeated site visits. For growing solar businesses, this helps standardise proposal quality, reduce turnaround time, improve customer trust, and increase lead conversion. 6,000+ solar EPC companies globally already run this workflow. For a closer, three-way comparison against Aurora Solar and Arka360 specifically, see here.

Strengths

Full 3D design on mobile phone, identical capability on desktop, no compromise either way
On-site closing: proposal on WhatsApp before leaving the roof
Auto-BOE and Bills of Structure from 3D design
Bank-ready SLD, layout, string drawings natively
PM Surya Ghar auto-calculation, ALMM compliance flag
3 kW to 1 GW in one platform, no tool switching
1 to 2 day onboarding for field teams

Limitations

Newest on this list.
Utility-scale PVsyst-equivalent bankable simulation: use PVsyst alongside for lender-mandated P90 reports on large projects

Best for: Solar EPCs across residential, C&I, open access, and utility-scale projects. Any geography, the US included. Any scale. Mobile-first 3D design, automated BOE, Bills of Structure, bank-ready documents, and CAPEX/OPEX proposals from one platform.

2. PVsyst

PVsyst is the global standard for bankable solar energy simulation. For utility-scale projects in India seeking debt financing from international or domestic lenders, the generation forecast in the lender's technical report will almost always be produced by or validated against PVsyst. Its hourly loss calculation methodology, detailed irradiance modelling, and P50/P75/P90 scenario outputs are what lenders and their independent technical advisors expect to see.

PVsyst is a desktop-first simulation tool, not a sales or proposal platform. It does not generate proposals, BOMs, or bank-format SLDs. It does not have mobile capability. It is an engineering simulation tool that EPCs use alongside a sales and design platform, not instead of one. For Indian EPCs managing projects above 1 MW with financing requirements, PVsyst is typically a mandatory addition to the software stack rather than a standalone choice. Where PVsyst and Reslink each fit into that stack is covered in full here.

Strengths

Global standard for bankable yield simulation
Accepted by all major Indian and international lenders
Deepest loss modelling methodology available
P50/P75/P90 scenario outputs for financing

Limitations

Desktop only, no mobile capability
No proposal, BOM, or sales workflow
Steep learning curve, weeks to proficiency
No India-specific compliance outputs (DISCOM, ALMM)
Not useful for residential EPC sales teams on its own

Best for: Utility-scale projects above 5 MW requiring bankable P90 simulation for lender due diligence. Use alongside a sales and design platform, not as a standalone EPC tool.

3. HelioScope

HelioScope is a well-regarded cloud-based design platform used primarily by commercial and industrial solar teams in the US and Europe. Its shade modelling is strong, its interface is cleaner than PVsyst for commercial-scale layouts, and it has good team collaboration features. It's browser-based and technically accessible from any device, but that's not the same as a purpose-built mobile field workflow, there's no touch-optimized, on-site design experience the way a dedicated mobile app provides. For Indian EPCs, the additional limitations are its US-centric financial and compliance outputs and the lack of India-specific integrations, PM Surya Ghar, ALMM, DISCOM workflows.

Strengths

Strong shade analysis for commercial layouts
Good team collaboration and project sharing
Clean interface, shorter learning curve than PVsyst
Accessible from any device via browser

Limitations

No dedicated mobile app or touch-optimized field workflow
US-primary financial and compliance outputs
No automated BOE or Bills of Structure
No bank-ready SLD for Indian authority formats
Requires separate proposal and BOM tools

Best for: office-based C&I solar teams already familiar with the platform, primarily for US and European projects.

4. Arka360

Arka360 started as a US solar proposal platform and expanded into India. Its proposal visual quality is high and it is used by commercial and industrial EPCs who need professional documentation for formal tenders. The 3D design is satellite-based and desktop-first. For Indian residential and field-sales teams, the lack of mobile design capability is a blocking constraint for on-site closing. PM Surya Ghar subsidy calculation requires manual configuration. ALMM compliance checking and automated BOE are not native features. The complete feature-by-feature comparison against Arka360 specifically is covered here.

Strengths

High-quality visual proposal output for commercial tenders
Accessible interface, moderate learning curve
India operations and support

Limitations

Desktop-first, no mobile 3D design
No automated BOE or Bills of Structure
No bank-ready SLD output natively
PM Surya Ghar and ALMM: manual configuration
Not viable for on-site closing workflow

Best for: On a fresh evaluation, comparison purposes against Reslink, there is no workflow where Arka360 has a clear advantage. Both do satellite 3D design and CAPEX proposals; Reslink does both equally well and adds everything Arka360 doesn't cover.

5. OpenSolar

OpenSolar is the only genuinely free-to-start solar design software on this list. Version 3.0, released in late 2025, expanded from a design tool into an integrated platform with CRM, pipeline management, and proposal generation. The core design, proposal, and CRM workflow remains free, monetised through hardware and financing partnerships rather than subscriptions, though as of April 2026 API access and third-party app connectors carry separate charges.

OpenSolar does generate bill-of-materials output through specific hardware partnerships, IronRidge among them, worth noting precisely rather than dismissing outright. That's narrower than BOM generated natively from the 3D design across any equipment selection, which is what determines accuracy on a specific project's actual layout, but it isn't accurate to say OpenSolar has no automated BOM capability at all.

The limitations that remain material as volume grows: India-specific compliance parameters, PM Surya Ghar, ALMM, DISCOM formats, require manual configuration. The roadmap is influenced by partner hardware integrations rather than purely by EPC operational needs. For EPCs scaling rapidly, the manual overhead of OpenSolar's India customisation typically justifies switching to a purpose-built platform.

Strengths

Core workflow free, no subscription cost
Integrated design, CRM, and proposal in v3.0
Bill-of-materials generation through hardware partnerships
Reasonable learning curve
Global coverage and hardware integrations

Limitations

India compliance parameters: manual configuration
BOM automation tied to specific hardware partnerships, not generated natively from the 3D design across any equipment
Roadmap driven by partner priorities, not EPC needs
API access and app connectors now carry separate charges
Not designed for mobile-first field workflows

Best for: teams with genuinely zero software budget evaluating their first design tool. The manual India-compliance configuration and the gap between partnership-based and design-native BOM accuracy are worth weighing against that zero cost as project volume grows.

6. Aurora Solar

Aurora Solar is the dominant solar design software for residential and C&I EPCs in the United States. Its depth of US utility rate integrations, financing product connections, and mature enterprise feature set reflect years of investment specifically in that market, and that depth is real. For Indian EPCs, the gaps are structural rather than incidental: it is desktop-first, has no mobile 3D design, does not generate automated BOE or Bills of Structure anywhere it operates, does not produce bank-ready SLDs in Indian DISCOM format, and has no native PM Surya Ghar or ALMM integration. Aurora's real US-specific strengths, and where the gaps show up even inside that market, are covered in full here.

Strengths

Strongest platform for US residential and C&I
Deep US utility rate and financing integrations
Mature enterprise feature set and support

Limitations

Desktop-first, no mobile design capability, in the US or elsewhere
US-primary architecture, limited India compliance
No automated BOE, Bills of Structure, or bank-ready SLD, in any market
US pricing calibrated for US market economics
Poor fit for Indian field sales workflows

Best for: comparison purposes against Reslink specifically on US market depth. Even within the US, Aurora doesn't cover BOE automation, Bills of Structure, or WhatsApp delivery, gaps that exist inside its strongest market, not just outside it.

Reslink vs Other Tools: Feature Comparison

What the table shows: Aurora Solar, Arka360, HelioScope, and OpenSolar each cover a piece of the workflow, design or proposals, but not the full downstream chain. PVsyst covers simulation depth better than anything else on this list, and isn't trying to cover the rest. Reslink is the only platform covering the complete workflow, in every row that isn't PVsyst's specific job.

Where Reslink's CRM Goes Further Than the Field

OpenSolar also has a built-in CRM, worth acknowledging directly rather than pretending it's a Reslink-only feature. The real difference is what each CRM is actually tied to. Reslink's CRM tracks a project through the specific DISCOM milestones an Indian solar project needs: feasibility submission, technical sanction, net metering application, inspection, and commissioning, connected to the same 3D design, subsidy calculation, and ALMM check that produced the proposal in the first place. A generic sales CRM tracks a deal. Reslink's tracks a deal through the compliance pipeline that determines whether it actually gets commissioned.

Proof, Not Just Promises

Freyr Energy, backed by Schneider Electric, moved its entire residential sales team onto Reslink specifically for the mobile-first design-to-WhatsApp workflow described throughout this comparison. CleanMax has also partnered with Reslink as part of its EPC operations.

The pattern holds at the project level too. A Rajasthan-based EPC saw a 30% increase in deal closure within its first month of switching to Reslink. A Nagpur-based commercial EPC closed a 500 kW project after presenting a 3D design with shadow analysis on-site, the kind of on-site, visual closing advantage that none of the five other tools in this comparison are built to produce.

Common Mistakes EPCs Make Comparing These Six Tools

Comparing feature checklists without checking BOM depth specifically. "Automated BOM" means something different depending on whether it's calculated from the actual 3D design or generated through a hardware partnership for specific equipment, the distinction matters once a project uses equipment outside that partnership.
Assuming "free" or "mobile-accessible" means the same thing across every platform. OpenSolar's free tier and Reslink's mobile-first workflow both use familiar words, but "free until you need an integration" and "browser-accessible" aren't the same as "purpose-built for a field sales workflow."
Evaluating only against the easiest segment of the business. A tool that looks adequate for straightforward residential rooftop projects can fall apart the moment a C&I customer asks for a PPA option or a project needs bank financing, check the tool against the hardest project in the pipeline, not the easiest.

What EPCs Should Do Now

Check whether the current design tool generates BOM natively from the 3D design, or only for specific partnered equipment.
Confirm whether "mobile capability" in a current tool means a real field design workflow, or just that a webpage loads on a phone.
Map the current workflow against the five criteria above, compliance, mobile, BOM, bank-ready documents, scale coverage, and note which ones are still manual.
Book a demo and compare a live design-to-proposal cycle against whatever's currently in use.

The Bottom Line

Six tools, one clear split. PVsyst wins simulation depth outright, and nothing here argues otherwise, it's the standard for a reason. Across every other criterion that determines whether an EPC's daily workflow actually functions, mobile capability, automated BOM, bank-ready documents, India-specific compliance, CRM tied to the compliance pipeline, Reslink is the only platform among the six that covers it, in India and in every other market it operates in, including the US.

How This Fits Into a Reslink Workflow

Every gap in this comparison traces back to the same pattern: five platforms were each built to be strong at one part of the job, US residential sales, commercial layout, a free entry point, bankable simulation, and left everything else for the EPC to handle separately. Reslink was built the other way, one 3D design generating the proposal, the compliance checks, the procurement documents, and the CRM record automatically, in whichever market that project happens to sit in.

See the complete workflow run end to end against a real project → Book a demo

Frequently Asked Questions

Q1. What is the best solar design software for Indian EPCs in 2026?

Reslink is the best solar design software for Indian EPCs in 2026. It is the only platform that supports 3D design on a phone, shadow simulation, automated BOE, Bills of Structure, bank-ready SLD, CAPEX and OPEX proposals, ALMM compliance, PM Surya Ghar subsidy calculation, and WhatsApp proposal delivery in one connected workflow. For utility-scale projects requiring bankable generation reports for lender due diligence, PVsyst remains essential, used alongside Reslink. For teams with genuinely zero software budget, OpenSolar is a real free starting point, though its India-compliance overhead and partnership-based BOM accuracy are worth weighing as volume grows.

Q2. Which solar design software is best for closing deals on-site in India?

Only Reslink is designed for a full field-based closing workflow. The 3D design, shadow simulation, proposal generation, and WhatsApp delivery all happen within the mobile app during the site visit, with the same capability the platform has on desktop. PVsyst and Arka360 require a desktop or laptop for the design step. HelioScope and OpenSolar are technically accessible from a phone browser but aren't built as a purpose-built field design workflow. Aurora Solar is desktop-first. In the Indian residential and commercial solar market, where the decision window is typically 24 to 72 hours and customers are comparing multiple EPCs simultaneously, on-site closing capability is a direct competitive advantage.

Q3. Does solar design software handle PM Surya Ghar subsidy calculations automatically?

Only Reslink includes PM Surya Ghar central subsidy calculation as a native, automated feature. The subsidy slab is calculated from the system size and displayed in the proposal without manual input. Other platforms in this comparison either do not support PM Surya Ghar (Aurora Solar, HelioScope, PVsyst) or require manual configuration of the subsidy slabs by the EPC before the calculation becomes available to the sales team (Arka360, OpenSolar). Manual configuration adds setup overhead and introduces the risk of incorrect slab values being used if the configuration isn't updated when MNRE revises the scheme.

Q4. What is the difference between a BOE and a Bills of Structure in solar projects?

The Bills of Electrical (BOE) covers all electrical components required for the installation: AC and DC cables with lengths calculated from the actual string layout, AC Distribution Board (ACDB), DC Distribution Board (DCDB), lightning arrestors, MC4 connectors, and earthing components. The Bills of Structure covers all mechanical mounting components: purlins, rafters, mounting heights, and structural specifications derived from the roof geometry and panel layout. Together, these two documents give the procurement team everything needed to order materials for the full installation, without preparing a separate BOM in Excel. Reslink generates both automatically from the 3D design, calculated across any equipment selection, not limited to specific hardware partnerships the way OpenSolar's BOM automation is.

Q5. Is PVsyst good for Indian solar projects?

PVsyst is the global industry standard for bankable solar energy simulation and is used for utility-scale projects in India where debt financing from banks or international lenders requires an independent technical report. For these projects, PVsyst is typically mandatory. Lenders' technical advisors expect to see P50/P75/P90 generation scenarios produced or validated by PVsyst. However, PVsyst is a simulation tool only. It does not generate proposals, BOMs, customer-facing documents, or India-specific compliance outputs. Most utility-scale EPCs in India use PVsyst alongside a design and sales platform like Reslink, not as a standalone solution.

Q6. Can solar design software generate DISCOM-compliant documents for Indian grid connections?

Yes, Reslink generates Single Line Diagrams (SLDs), layout drawings, and string drawings in a format that meets Indian DISCOM and bank submission standards without requiring post-export modification. This is described as bank-ready document output. No other platform in this comparison offers this as a native feature.

Q7. How long does it take to learn solar design software for a field sales rep in India?

This varies significantly by platform. Reslink is designed for non-technical sales representatives and typically takes 1 to 2 days to reach operational proficiency. The mobile interface is optimised for speed and field use and requires no technical depth. Arka360 typically takes 1 to 2 weeks. HelioScope and Aurora Solar take 2 to 4 weeks. PVsyst requires weeks of training and is designed for experienced engineers, not field sales representatives. For EPCs with high field team turnover, platforms with short onboarding timelines reduce the cost of getting new reps productive.

Q8. Is solar design software worth the investment for a small Indian EPC?

The ROI calculation for solar design software has two components: cost savings from eliminating manual proposal and BOM preparation, and revenue increase from improved close rates when proposals are delivered faster and with better content. For an EPC doing 15 to 20 projects per month, manual proposal preparation typically costs 2 to 3 hours per project in engineer or admin time. At 15 projects, that's 30 to 45 hours per month of avoidable overhead. EPCs using Reslink typically see up to a 30% improvement in lead conversion within the first month itself.

Q9. What is the best solar design software globally in 2026?

There is no single best solar design software globally, the right choice depends on the market, project type, design depth, documentation needs, and sales workflow. That said, Reslink's adaptability makes it one of the strongest choices for solar EPCs anywhere, including the US, because it brings satellite-based 3D design, energy simulation, automated BOE, Bills of Structure, proposal generation, and bank-ready documentation into one platform rather than requiring several. For utility-scale projects that require highly bankable yield reports accepted by international lenders, PVsyst remains the simulation standard, used alongside a platform like Reslink rather than in place of one. For EPCs connecting design, proposal, BOM, financial modelling, and documentation into a single workflow, Reslink is built around the complete EPC workflow, not just standalone design.

Q10. Does solar design software work for EPCs in Europe, Australia, the Middle East, and the US?

Yes, though the degree of local market adaptation varies significantly by platform. In Europe, EPCs need tools that support EU grid connection standards, local DNSP documentation formats, and country-specific feed-in tariff structures. In Australia, AS/NZS 5033 compliance and Clean Energy Council accreditation documentation are key requirements. In the Middle East, projects often require DEWA, SEC, or PAEW grid connection formats. In the US, NEC-format SLDs and US utility rate integrations are the standard, Aurora Solar's specific strength. Reslink's geographic adaptability architecture incorporates local grid codes, irradiance data, and compliance requirements per market, including the US, making it viable across all of these regions without requiring EPCs to manually configure local parameters from scratch. PVsyst supports all of these markets for simulation purposes. HelioScope is strongest for US and European commercial layouts specifically.

Q11. Can the same solar design software be used across multiple countries?

Yes, for EPCs operating across multiple geographies, for example an Indian EPC expanding into the UAE and Australia, or a US-based developer taking on projects in Southeast Asia, a geographically adaptable platform avoids the cost and training overhead of maintaining different tools per country. The key requirement is that the platform incorporates location-specific irradiance data, local grid codes and compliance outputs, and local financial parameters, tariff structures, incentive schemes, currency, per project, rather than defaulting to a single market's standards. Reslink is built around this geographic adaptability, with India as the deepest current localisation and active market expansion covering the US, the Middle East, Southeast Asia, Africa, Europe, and Australia. PVsyst supports international projects for simulation purposes across all markets.

Sources

MNRE, PM Surya Ghar Muft Bijli Yojana subsidy guidelines, current edition
MNRE, ALMM List I and II, current edition
IEA, India solar capacity statistics
IRENA, Renewable Power Generation Costs
PVsyst, product documentation
Aurora Solar, product documentation
Arka360, product documentation
OpenSolar, product documentation and pricing update, April 2026
HelioScope, product documentation
Reslink, platform documentation and customer data
Mercom India, India Solar EPC Market Report
Bridge to India, India Solar Market Overview

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