Justworks vs TriNet for Commercial Solar and Energy EPC Firms

Start with a simple table: state, number of crew members based there, and whether you have any current or upcoming utility-scale or public-sector project in that state. A firm running two crews in one home state has a very different PEO need than one bidding jobs in six states this year, and this row alone should tell you roughly how much multi-state administrative depth you actually need before you look at pricing. Update this table quarterly rather than once at the start of the year, since a fast-growing EPC firm's footprint can shift meaningfully within a single project cycle.

Certain federal clean energy tax credit rules require paying prevailing wages and meeting apprenticeship ratios on qualifying projects, a status your tax advisor and project developer need to confirm project by project, since eligibility is technical and depends on project size and structure. Mark each active or bid project where this applies, because it changes what documentation your payroll records need to support, separate from whatever your PEO handles day to day.

Solar installation and energy field work carries real physical risk, working at height, handling electrical systems, operating lifts and heavy equipment, and that needs to be reflected accurately in your workers' compensation classification codes rather than a generic construction or electrical contractor code that may not match your actual work. Ask each vendor for examples of how they've classified solar or energy EPC crews specifically, not general construction.

If your projects carry apprenticeship ratio requirements, you likely already have a training pipeline or a relationship with a training provider, and it's worth asking each PEO how their benefits and payroll setup accommodates apprentice pay scales, which often differ from journeyman rates and may change on a defined schedule tied to hours or time in the program. Getting an apprentice's pay step wrong even once is the kind of detail an auditor checks specifically on a project with wage and apprenticeship requirements attached, so this row deserves more than a passing glance.

For a firm still concentrated in one or two states with mostly private commercial projects, a self-serve PEO such as Justworks may keep overhead low while you're still establishing your project pipeline, but confirm current pricing and any prevailing-wage or certified payroll needs. It's a reasonable starting point if your worksheet shows limited multi-state spread and no heavy prevailing wage documentation burden yet.

If your worksheet shows crews in several states, a mix of prevailing wage and non-prevailing wage projects, and workers' comp exposure that needs careful classification, TriNet's deeper multi-state administration and more active claims involvement are worth the added cost. Firms scaling from one region into utility-scale, multi-state work tend to find this the point where the extra depth pays for itself.

Once you've filled in all four rows, the pattern should be clear: a firm with a short list of in-state, private projects leans Justworks, while a firm with a growing, multi-state list including prevailing wage work leans TriNet. Construction and energy contractors generally run payroll costs close to a fifth of revenue in a given year¹, which is high enough that getting this decision right has a real, measurable effect on your margin, not just an administrative convenience.

How to read your finished worksheet:

• A short list of in-state, private projects points toward Justworks and its simpler, lower-overhead setup.
• A growing multi-state project list that includes prevailing wage work points toward TriNet and its deeper administration.
• Rerun the worksheet before every bid that would put crew in a state you have not worked in before.
• Keep the state table current each quarter, since a fast-growing EPC firm's footprint can shift within a single project cycle.

The worksheet isn't a one-time exercise, it's worth pulling out again every time you're preparing a bid that would put crew in a state you haven't worked in before, since that's exactly the moment your PEO's multi-state capability gets tested for real. Growing EPC firms often spend most of their strategic planning time on equipment financing, bonding capacity, and project financing instead, treating the HR side of scaling as an afterthought handled by whoever has spare time. Given how much workers' comp classification and multi-state compliance actually cost you when they're wrong, it's worth giving this worksheet the same deliberate attention you'd give a financing decision of similar size, rather than defaulting to whichever PEO a peer contractor happened to mention in passing.