Comparison

PROSILI vs HOMER Pro: An Honest Comparison for Mini-Grid Engineers

HOMER Pro has been the industry standard for hybrid system simulation since the early 2000s. PROSILI is a newer, browser-based alternative built specifically for energy access pre-feasibility work. Here's where each tool fits, what they share, and where they differ.

Updated April 2026 · 6 min read

Quick Summary

Both tools run hourly dispatch simulations of PV + battery + diesel hybrid systems over 8,760 hours. Both calculate LCOE, NPV, renewable fraction, and can generate sensitivity analysis. The core engineering methodology is the same — the CRF-based LCOE approach used by both platforms typically produces results within 3–8% of each other for equivalent input configurations.

The key differences are access model (desktop license vs. free browser tool), scope (HOMER covers a wider range of generation technologies), and context (PROSILI is purpose-built for DFI-aligned energy access pre-feasibility work).

Feature Comparison

Feature PROSILI HOMER Pro
Price Free ~$500–1,500/year
Platform Browser — any device Windows desktop
Installation required No Yes
Hourly dispatch simulation (8,760 hr)
LCOE calculation (CRF method)
NPV / financial analysis
Sensitivity analysis
Solar resource (automatic) NASA POWER Multiple sources
PDF pre-feasibility report ✓ (DFI-aligned) Basic export
Single Line Diagram generator ✓ (47 components)
Wind turbine modeling
Hydro modeling
Grid-connected mode
Multi-objective optimization
PAYG / productive use modeling
Load profile templates (Africa) Generic
Internet required Initial load only No (desktop)
Data privacy All data stays in browser Local machine

Where PROSILI Fits Best

PROSILI is designed for a specific use case: pre-feasibility analysis of isolated PV + battery + diesel mini-grids in energy access contexts. If you're a developer, consultant, or engineer preparing a feasibility study for a rural electrification project — particularly one funded by the World Bank, AfDB, IFC, GIZ, or similar institutions — PROSILI generates the report format and metrics these funders expect.

It's also the right tool when you need something quick and accessible: no license procurement, no Windows-only restriction, no installation on shared office computers. Open a browser tab, run a simulation, download the PDF. This matters in contexts where teams share hardware, work on laptops with limited admin rights, or need to iterate fast during proposal development.

The SLD Advantage

PROSILI includes something HOMER doesn't offer at all: a Single Line Diagram generator with 47 IEC 60617-compliant electrical component types, four auto-generation tiers (from small DC-coupled systems to utility-scale MV installations), and professional PDF export with ISO 7200 title blocks. For engineers preparing regulatory submissions or detailed feasibility documents, this eliminates a separate step and a separate tool.

Where HOMER Pro Is Stronger

HOMER Pro covers a much wider range of generation technologies — wind, hydro, hydrogen, CHP, and grid-connected scenarios. If your project includes wind turbines, hydrokinetic resources, or grid-tied operation, HOMER is the right choice. HOMER also offers multi-objective optimization, searching across thousands of system configurations to find the least-cost design, whereas PROSILI simulates the configuration you specify.

For utility-scale projects, detailed component library customization, or academic research requiring the broadest possible technology coverage, HOMER Pro's depth is unmatched. It's been the standard for over two decades for good reason.

Methodology Alignment

PROSILI targets a ±5% deviation from HOMER Pro for equivalent PV + battery + diesel input configurations. Both use the CRF-based LCOE calculation method, which is the industry standard used by regulatory bodies and development finance institutions. Both run 8,760-hour hourly dispatch with battery state-of-charge tracking, generator minimum loading constraints, and PV derating. Differences in results typically arise from solar data source variations (NASA POWER vs. HOMER's resource databases) and specific battery degradation modeling assumptions.

Who Should Use Which?

Use PROSILI if: You're doing pre-feasibility for an isolated mini-grid (PV + battery ± diesel), you need a DFI-aligned PDF report, you want a free tool with no installation, you need an SLD, or you're working in a context where HOMER's license cost or Windows requirement is a barrier.

Use HOMER Pro if: Your project includes wind, hydro, or grid-connected configurations, you need multi-objective optimization across many system designs, or you're doing deep academic research requiring HOMER's full component library.

Use both if: You want to cross-validate results. Running the same inputs through both tools and comparing outputs is a sound engineering practice that strengthens your feasibility study.

Try PROSILI — Free, No Installation

Run your first 8,760-hour mini-grid simulation in under 10 minutes. Export a professional PDF report. Generate an SLD. All in your browser.

Launch PROSILI →

Frequently Asked Questions

Is PROSILI really free?

Yes. All simulation, analysis, and export features are currently free with no account required. We plan to introduce optional paid tiers in the future for advanced features, but the core simulation engine will remain accessible.

Can I use PROSILI results in a bankable feasibility study?

PROSILI generates pre-feasibility level results — suitable for project screening, concept design, and initial DFI submissions. For bankable feasibility (investment-grade), you would typically complement simulation results with on-site resource measurements, detailed engineering design, and independent technical review, regardless of which simulation tool you use.

Is my data safe?

All simulation data is processed entirely in your browser. No project data is transmitted to or stored on any server. Your engineering work stays on your machine.

Does PROSILI work on Mac / Linux / mobile?

PROSILI works in any modern browser on any operating system — Mac, Windows, Linux, ChromeOS. The simulation tools require a screen width of at least 768px (desktop/laptop), so mobile phones are not supported for the studio interface, though the landing page and information pages are fully responsive.