SunProjeX vs OpenSolar
OpenSolar gives away PV design software, and it is good at that. But it is photovoltaic only. Solar pool heating and hot water are a different trade, and SunProjeX is built for it.
OpenSolar is a genuinely free, capable photovoltaic design and proposal platform used by installers worldwide, monetized through hardware and lender partnerships rather than seat fees. Confirmed on its site as of July 2026, it designs PV. It does not size or design solar pool heating or solar hot water.
SunProjeX is the tool for the thermal trade OpenSolar does not serve: swim-season pool heating sizing, demand-and-offset hot water on FSEC and SRCC certified ratings, collector layout, and proposals that can carry both systems at once.
| SunProjeX | OpenSolar | |
|---|---|---|
| Solar pool heating design | Yes — swim-season sizing and collector layout | PV only, no thermal |
| Solar hot water (DHW) design | Yes — demand-and-offset, FSEC and SRCC certified | PV only, no thermal |
| Certified thermal sizing | Yes — FSEC and SRCC certified thermal sizing | no thermal sizing |
| PV (electric) array design | SunProjeX is solar thermal, not PV | Yes — free PV design and proposals |
| Customer proposals and e-sign | Yes — branded proposals, e-signature, deposit CTAs | Yes — PV proposals |
| Combo pool + hot water proposal | Yes — pool heating and hot water in one proposal | No |
| Built for the solar thermal trade | Yes — built for the solar thermal trade | built for PV installers |
| Pricing model | Yes — free trial, founding program available | Free PV software, monetized via hardware/lender partnerships plus API and connector fees |
Comparison reflects publicly available information about OpenSolar and our own product as of July 2026; product features change, so verify current details on their site. OpenSolar is a trademark of its respective owner.
Its core PV design software is free; it monetizes through hardware and lender partnerships and, since April 2026, API and connector fees. But it is photovoltaic only.
No. It designs PV. Solar pool heating and hot water are handled by SunProjeX.
The only design and proposal software built for solar pool heating and hot water.
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