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Head-to-head · Solar Software

OpenSolar vs System Advisor Model (SAM)

  • Updated Oct 2026
  • Both researched from official sources
  • 6 checks side by side
Higher score OpenSolar #1 in Solar Software 9.2/10 Free plan · 30-day trial Free planFree trial✓ 0 of 5 features Visit OpenSolar
System Advisor Model (SAM) #8 in Solar Software 8.1/10 Free plan Free plan✓ 2 of 5 features Visit SAM

OpenSolar leads on 0 checks, System Advisor Model (SAM) on 0, and 6 are even. Who comes out ahead on the 6 yes/no, price and count checks where we have data for both products. The editor score weighs everything else too.

Our verdict

  • Highest scoreOpenSolar · 9.2/10
  • Free planboth
  • Free trialonly OpenSolar
  • Most featuresSystem Advisor Model (SAM) · 2 of 5

OpenSolar scores higher on our rubric for solar software: 9.2 against 8.1 out of 10; our editors rank them #1 and #8.

OpenSolar is the better fit for solar teams wanting an end-to-end workflow at no cost. System Advisor Model (SAM) is the better fit for analysts seeking free, scriptable PV and financial modeling.

  • OpenSolar fits best

    Solar teams wanting an end-to-end workflow at no cost

  • System Advisor Model (SAM) fits best

    Analysts seeking free, scriptable PV and financial modeling

Advertiser disclosure: iTechGuides is reader-supported. Vendors can pay for top positions in our rankings and for a place on other products' pages, and we may earn a commission when you click some links. Bought places stand at the number bought; this page and our disclosure say so. Paying vendors may get a fuller, more detailed review from our editors, and that review can change their score. How we rank.

Side by side

Feature OpenSolar 9.2/10 Visit ↗ System Advisor Model (SAM) 8.1/10 Visit ↗
At a glance
Editor score 9.2 8.1
Ranking #1 in Solar Software #8 in Solar Software
Best for Solar teams wanting an end-to-end workflow at no cost Analysts seeking free, scriptable PV and financial modeling
Pricing model Free plan + paid Free
Starting price — Free plan
Free plan ✓ ✓
Free trial 30 days —
Deployment Cloud Desktop
Platforms Web, iOS, Android Windows, macOS, Linux
Support Docs Community, Docs
Built for Small business, Mid-market, Enterprise Small business, Mid-market, Enterprise
Features OpenSolar 0/5 · System Advisor Model (SAM) 2/5
PV design & simulation Not checked yet ✓ (best)
Financial modeling Not checked yet ✓ (best)
Proposal builder Not checked yet —
System monitoring Not checked yet —
Permit documentation Not checked yet —
Specs
Deployment platform Not checked yet Desktop
Our review
Pros
  • Free core app includes design, proposals and project management.
  • Combines CRM, financing, e-signature, payments and equipment ordering.
  • Web and mobile apps, plus integrations with tools such as Xero and Google Calendar.
  • Detailed PV modeling includes module, inverter, shading, and loss calculations.
  • Models cash flows across residential, PPA, community solar, and other project types.
  • Parametric and stochastic simulations, P50/P90 analysis, and an SDK/API are available.
Cons
  • API access and selected connectors are paid add-ons.
  • API and connector pricing varies by region or organization.
  • API access has a 30-day free trial rather than being part of the free core app.
  • Desktop software rather than a web-based platform.
  • Does not include proposal-building features.
  • Does not include monitoring portals or permit sets.
Our verdict

Solar installers and electrification professionals can use OpenSolar to manage work from system design through project delivery. Its free Core OpenSolar app combines AI-assisted solar design, customizable proposals, CRM, project…

Read the review →

System Advisor Model (SAM) is free, open-source desktop software from the National Laboratory of the Rockies for analyzing the technical and financial feasibility of power-generation projects. It is aimed at project managers, engineers,…

Read the review →
  1. OpenSolarSolar Software 9.2Free plan · 30-day trial
  2. System Advisor Model (SAM)Solar Software 8.1Free plan

Strengths and trade-offs

  • OpenSolar — where it wins

    • Free core app includes design, proposals and project management.
    • Combines CRM, financing, e-signature, payments and equipment ordering.
    • Web and mobile apps, plus integrations with tools such as Xero and Google Calendar.

    Where it doesn't

    • API access and selected connectors are paid add-ons.
    • API and connector pricing varies by region or organization.
    • API access has a 30-day free trial rather than being part of the free core app.

  • System Advisor Model (SAM) — where it wins

    • Detailed PV modeling includes module, inverter, shading, and loss calculations.
    • Models cash flows across residential, PPA, community solar, and other project types.
    • Parametric and stochastic simulations, P50/P90 analysis, and an SDK/API are available.

    Where it doesn't

    • Desktop software rather than a web-based platform.
    • Does not include proposal-building features.
    • Does not include monitoring portals or permit sets.
  • OpenSolar9.2/10 · Free plan · 30-day trial

    A free core app covers solar design, sales and project management in one workflow.

    Visit OpenSolarFull verdict →
  • System Advisor Model (SAM)8.1/10 · Free plan

    Open-source PV and project-finance modeling for analysts who want desktop tools and scripting.

    Visit SAMFull verdict →

More comparisons

All solar software comparisons → · Full ranking →

Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026

Last updated · How we research and update