The short answer: an ASTM E2848 capacity test costs anywhere from $599 to $5,000+ per site, depending on who runs it. That is a wide range, and the difference is not test quality — it is how much of the work you do yourself.
There are exactly three realistic ways to get a contractual capacity test done, and this page compares them directly. Prices are stated because you should be able to qualify an option before you talk to anyone — us included.
| Typical cost | Who does the work | Typical turnaround | |
|---|---|---|---|
| Hire a consultant | $3,000–$5,000+ per site | They do | Varies by firm |
| Run it in-house with software | From $599 one-time | You do, guided | Hours once data is in hand |
| HelioTest-managed test | From $2,500 per site, fixed quote | We do | 3–5 business days from data receipt |
All three produce the same thing when done right: a defensible test result per ASTM E2848, documented in a report your counterparty can audit.
What You Are Actually Paying For
The regression at the heart of an E2848 test is a few minutes of computation. The cost — whoever bears it — is everything around it:
- Data preparation. Extracting measured power, irradiance, and temperature from your monitoring system, mapping columns, and validating sensor coverage and timestamps.
- Filtering. Applying the standard's data filters (irradiance range, clipping, outliers, stability) and documenting every step — the most disputed stage of any test.
- The model side. Obtaining the as-built PVsyst simulation's hourly output and deriving the reporting conditions the test is evaluated at.
- Reporting. Producing a document that states the acceptance criteria, the filtering waterfall, and the regression details explicitly. Here is what that looks like in practice.
Keep that list in mind as you read the options — each one is a different answer to "who does this work."
Option 1: Hire a Consultant — $3,000–$5,000+ per Site
An engineering consultancy runs the test end to end and delivers a stamped report. This is the traditional route, and for some situations it is the right one: your contract or lender specifically requires a named independent engineering firm, or the engagement involves bespoke analysis beyond the standard test.
What to watch for: the deliverable is usually a PDF with limited visibility into the filtering and regression decisions behind it, and if the test fails and needs a retest after remediation, the second engagement typically costs again. At $3,000–$5,000+ per site, a portfolio of tests adds up quickly — our consultant vs. in-house framework covers when the economics flip.
Option 2: Run It In-House With Software — From $599
If someone on your team is comfortable working with monitoring-data exports (CSV files) and you have the plant's PVsyst model, you can run the test yourself in HelioTest. The platform handles the mechanics — column mapping, filtering, regression, reporting conditions — through a guided workflow, and generates the audit-ready PDF report automatically.
- Single Test — $599, one-time. One site for 90 days, up to 200 test runs (retests after a fix cost nothing), stakeholder-ready PDF reports, and SolarEdge/AlsoEnergy integrations. No subscription. If you upgrade to an annual plan within 90 days, the $599 is credited.
- Premium — $999 per year. Up to 3 sites per year — the break-even against a single consultant engagement is immediate.
- Free tier. Run a complete test on your own data (without the PDF export) before paying anything.
Full details on the pricing page.
Option 3: A Managed Test — From $2,500 per Site
The middle route: we run the test for you on the same platform, per your contract's requirements — data validation, test configuration, execution, QA, and the full deliverable package (PDF report, data export, Excel recalculation workbook, live platform access). Turnaround is typically 3–5 business days from complete data receipt. Scope and price are fixed in a quote after a 30-minute scoping call, since site complexity and your contract's test exhibit drive the effort.
This comes in below the consultant range while including more — platform access, the working files, and the option to run the next test yourself — and unlike a consultant's PDF, every filtering and regression decision remains inspectable. The managed testing service page describes exactly what is included and what you need to provide.
What Can Add Cost — Whatever Route You Pick
- A failed first test. Failed tests trigger an investigate-fix-retest cycle. With software, a retest is a re-run within your plan; with a managed test, a re-run is quoted separately; with a consultant, clarify retest pricing before you sign.
- Missing model data. The test needs the PVsyst simulation's raw hourly output, not the summary report. Chasing down or rebuilding a model adds time and sometimes cost.
- Complex sites. Bifacial modules, multiple array orientations, or GHI-only sensor setups add analysis steps. HelioTest handles these natively; elsewhere they can mean change orders.
- Deadline pressure. Capacity tests sit on the critical path to substantial completion. The expensive scenario is not the test — it is the weeks lost redoing one that was set up wrong.
Which Option Fits You?
The software route is the right fit when you can say yes to all four of these:
- You are comfortable opening a CSV of your monitoring data and making sense of its columns.
- You have (or can get) the plant's PVsyst model.
- You have basic PV system knowledge — you know what your inverters, irradiance sensors, and meter measure, and roughly how the plant should behave.
- You understand the principle of the test, or are willing to dive into it. The platform handles the mechanics, but you make the calls the standard leaves to the tester — our E2848 guide covers the principles in one read.
Four yeses: the software route at $599 will do the job for a fraction of the alternatives. Any no — or you would simply rather have the whole thing handled — a managed test comes in below a traditional consultant engagement and keeps every step transparent.
For a fuller breakdown of who typically runs these tests and what contracts require, see who can perform an ASTM E2848 capacity test.
Get a Fixed Quote for Your Site
The honest answer to "what will my test cost" depends on your site's complexity and the state of your data — both of which we can assess in a 30-minute scoping call. You will leave with a fixed per-site quote and a realistic timeline, whichever route you choose.
Want to see what you would be paying for? Download the sample ASTM E2848 capacity test report — free, no sign-up.
Peter is an engineer with a PhD in renewable energy management and over a decade of experience in software development for renewable energy applications. He built HelioTest to replace the fragile spreadsheet workflows he encountered across dozens of ASTM E2848 capacity tests.
