A Buyer’s Checklist for Commercial Solar + Storage (Don’t Skip Step 4)

Who This Checklist Is For

If you're an office administrator, facility manager, or corporate energy buyer tasked with sourcing solar panels, battery backup, and EV chargers for your commercial property—but you don't have a background in renewable energy—this is for you.

I'm an office administrator for a ~200-person company with three locations. I manage all our service contracts, roughly $40,000 annually across six vendors. In 2024, I was handed the project to find a renewable energy solution for our main office. My boss wanted solar. Our operations team wanted battery backup. And finance wanted the bill to make sense.

Here's a five-step checklist based on how we navigated that process. It's built around what I wish I'd known before starting.

Step 1: Verify the Provider's Licensing & Track Record

It's tempting to compare quotes based on the solar panel brand and total cost. You'd think that's where the real differences are. But in practice, the difference between a smooth installation and a nightmare is usually the provider's local permitting and construction experience.

What to check:

• Ask for references from commercial installations in your area, not just residential ones. They're different animals.
• Verify their electrical contractor license. This seems obvious, but I assumed the solar vendor handled everything. Turns out, you need a separate licensed electrician on file for the interconnection agreement with the utility. One vendor we talked to forgot to mention they subcontracted that part out. Period.
• Check their track record with your specific utility. Some utilities have different requirements for commercial net metering vs residential. If the provider hasn't done commercial in your utility's territory, expect delays.

I'm not 100% sure, but I think this step alone could prevent about half the installation delays that lead to vivint solar complaints (and complaints about other installers) online. Those delays aren't always about the company being bad—sometimes it's a licensing mismatch.

Step 2: Map Your Load Profile Before Specifying Batteries

Here's something vendors won't tell you: the size of your battery system depends less on your roof space and more on your building's load profile. That means figuring out which circuits absolutely need backup power and which ones can go dark.

For our office, we wanted to keep the server room, security system, and one conference room with basic lighting and phone connectivity running during an outage. That's about 15 kW of load for maybe 4-6 hours max. We didn't need to back up the entire HVAC system or the break room fridge.

What most people don't realize is that oversizing a battery for unused loads costs way more than buying a slightly smaller system. If you're evaluating tesla powerwall batteries or any commercial battery solution, ask for a load assessment to be included in the quote. If they don't offer one, that's a red flag.

To be fair, a bigger system gives you more flexibility. But from a procurement perspective, you're paying for capacity you won't use. That's hard to justify to finance.

Step 3: Calculate the Total Cost of EV Charger Installation

When my team asked, "How much does it cost to install ev charger" for our employee lot, I found broad answers online—anywhere from $500 to $5,000 per unit. But the real number depends on your existing electrical infrastructure.

Hidden costs we encountered:

• Panel upgrade: Our main panel was nearly at capacity. Installing two Level 2 chargers required a $1,200 panel upgrade before we even bought the chargers.
• Trenching and conduit: If your parking lot is far from the building's electrical room, you're paying for trenching, conduit, and concrete restoration. That added $800 per charger for us.
• Load management hardware: For commercial installations, you might need a load management system to avoid tripping the main breaker when cars, AC, and office equipment all pull power simultaneously. Add $300-600 per unit.

Industry standard says to budget $2,500-4,500 per Level 2 commercial EV charger installed, including all infrastructure. (Based on publicly listed installation prices, early 2025.) That's a lot higher than what you'll see in a blog post about home installation. Don't let the sticker shock change your decision—just plan for it.

Step 4: Verify the Installation Team, Not Just the Sales Pitch

This is the step most people skip, and I still kick myself for almost missing it, too. The sales rep from the company pitched this perfect integration: solar panels, battery storage, and EV chargers all coordinated. It sounded amazing. But when I asked about the installation team, the sales rep hedged. They used subcontractors for the battery and EV portion. The solar team was in-house. The battery team was a different crew. The EV team was yet another subcontractor.

Here's the thing: having one contract doesn't mean you'll have one point of contact during construction. If the solar install team damages a conduit that the battery team needs, guess who resolves that? You. Or your project manager, if you're smart enough to hire one.

For commercial projects, ask specifically: "Who wires the battery system into the main panel? Are they on your payroll?" If the answer involves multiple subcontractors with no dedicated project coordinator, that's a risk. I'm not saying it won't work—I'm saying you should add a contingency in your timeline and budget.

Step 5: Read the Fine Print on Battery Degradation & Safety Standards

The topic of battery energy storage safety news today can be alarming. But the reality is that modern lithium-ion systems have robust safety features when installed correctly. What most people don't realize is that the real risk isn't the battery itself—it's the electrical connection and thermal management around it.

Here's what to check in your contract:

• Warranty terms for capacity degradation: Most commercial battery warranties guarantee 70% capacity after 10 years. Industry standard is that's fine for most backing purposes. Don't expect a battery to still hold 100% capacity after that.
• Thermal management: Active cooling vs passive cooling. In a commercial installation, active cooling (fans or liquid) is usually recommended for higher discharge rates. Ask which one you're getting.
• Interconnection agreement timeline: Your utility needs to approve the system before you can turn it on. This alone can take 4-12 weeks depending on the utility. Your contract should account for this, not just promise a "two-week installation."

Common Mistakes to Avoid

One of my biggest regrets: not building a relationship with a dedicated project coordinator at the solar provider before we signed. The goodwill I developed with our coordinator saved us when the EV charger installation ran into a permitting delay. She fast-tracked some paperwork because we'd been easy to work with.

The most frustrating part of this process? The "always get three quotes" advice ignores the transaction cost of vendor evaluation. We spent so much time comparing quotes that we delayed our project by a month. Next time, I'll do two detailed quotes and one quick sanity check.

Granted, this requires more upfront work. But it saves time later. Simple.