Energy Optima vs PVsyst

What PVsyst does genuinely well

For PV yield assessment, PVsyst is the industry reference. If your deliverable is a PV energy yield report that a lender or independent engineer will accept, PVsyst is very often the expected tool.

• Deep PV modelling. 3D near-shading and horizon analysis, bifacial modelling, module mismatch, MPPT-level string sizing and a comprehensive loss tree.
• Mature, validated and widely accepted. Decades of use, extensive validation against operating plants, and near-universal recognition among PV engineers.
• Rich component libraries for modules and inverters, backed by manufacturer data.
• Batch and parametric tooling through its own interfaces for multi-variant studies.

Where PVsyst is not built for BESS economics

Battery support exists (added in the 7.x line): you can attach a battery, set capacity and power, and inspect state-of-charge. What it is not designed to do is drive a bankable storage business case.

• Degradation is not the centre of the model. Calendar versus cycle ageing and C-rate-dependent fade — the things that decide replacement timing — are not modelled with the same depth as PV losses.
• Dispatch is limited. There is no economic or predictive MPC dispatch against a tariff structure, and no LP-optimized storage sizing.
• Financial outputs are thin. PVsyst produces energy; NPV, IRR, LCOE and 25-year cashflow with augmentation are largely outside its remit.
• Desktop and single-user. Collaboration, API automation and multi-user project libraries are not the design centre.

What Energy Optima does

• Storage-first economics: degradation from manufacturer tables, LP sizing, economic and predictive dispatch.
• 25-year financials with augmentation planning, NPV, IRR and LCOE on paid tiers (payback on free).
• Strong — though not PVsyst-deep — PV modelling: multi-array design, MPPT string sizing, a 10-category IEC 61724 loss waterfall.
• Report generation for engineer, investor and owner audiences, plus API access on Team and above.

Where PVsyst beats us

On pure PV: PVsyst wins. Its 3D shading and bifacial treatment are more detailed, its validation record with lenders is longer, and it is what many independent engineers expect to see on a PV-only yield report. If your project has no battery and no storage business case, Energy Optima is not the better tool and we would not pretend otherwise.

Feature comparison

Assessment based on published documentation and each tool's documented modelling approach. PVsyst's battery features have expanded across releases — confirm the current version's capabilities against its own documentation before relying on any limitation described here.

Which should you choose?

Frequently asked