Sunnova Solar Power for Businesses: Leases, String Inverters, and Battery Backup That Actually Fit

I manage purchasing for a 45-person engineering company. I report to operations and finance, which means I'm the one who gets asked whether we should go solar, what it will actually cost, and why the quote from the sales rep doesn't look like the calculator on the internet. I'm not a solar engineer. My experience is based on roughly 30 vendor evaluations—or maybe 27; I'd have to check my spreadsheet—so take the installer-specific details with a grain of salt.

If you're also an admin or facility buyer looking at Sunnova solar power, you've probably noticed most articles are written for homeowners. This one is for businesses. And the first thing I'll tell you is that there is no single 'best' Sunnova setup for every company. The right system depends on three things: when you use electricity, what happens during an outage, and whether EV chargers are in your future.

First, separate the three main scenarios

I think about commercial solar like I think about any large purchase: different situations get different specifications. Here's the shortcut I use with our managers.

• Scenario 1 – High daytime usage, no backup requirement. You need low-cost solar and a straightforward inverter.
• Scenario 2 – Outages hurt your operations. You need battery backup, and the battery chemistry matters.
• Scenario 3 – EV charging is coming. You need solar, storage, and chargers designed together.

Scenario 1: High daytime usage, no critical outage needs

If your company runs from 8 a.m. to 6 p.m., uses air conditioning, and doesn't have equipment that has to stay on overnight, you're in Scenario 1. Your goal is to lower the cost per kilowatt-hour and keep maintenance simple.

For this, a Sunnova solar lease plus a string inverter is often the most cost-effective route. Here's where I'll say something that surprises people: a string inverter is not 'old technology.' That idea is a holdover from the early residential solar boom, when shade on one panel could drop the output of an entire string. On a flat commercial roof with no significant shading, a string inverter is cheaper, easier to service, and means fewer electronics on the roof. I'd rather replace one inverter at ground level than pay a technician to climb up and swap microinverters under panels.

This setup worked for us because we're a single-site company with predictable daytime demand. If you're running a two-shift factory or a data closet with 24/7 cooling, the calculation changes. In that case, you're closer to Scenario 2 or a custom design.

One administrative note: ask for access to the Sunnova portal during the contract review, not after installation. I use it to check monthly production against the invoice. The portal looks the same whether you have a small lease or a large one. That matters to me because I've been on contracts where the vendor portal was an afterthought for small customers.

Scenario 2: Outages are not acceptable (Tesla Powerwall Leavenworth, this is for you)

If your business has ever closed for half a day because the power flickered, you're in this bucket. If you're in the Leavenworth area, 'Tesla Powerwall Leavenworth' is probably one of the first searches you've tried—winter storms, falling trees, and rural feeder outages knock businesses offline. Tesla Powerwall is a proven product—I've recommended it to a restaurant owner in Leavenworth who needed to keep a walk-in cooler and POS system running through a storm. I'm not going to talk you out of it.

What I will do is make sure you compare it to a Sunnova LFP battery before you sign. LFP stands for lithium iron phosphate, and it handles partial charging much better than older lithium-ion formulations. That's exactly what a business does during an outage: you're not doing a pretty charge cycle; you're taking power when the grid flickers and charging the battery as solar allows. Sunnova's LFP battery option also includes a heated housing, which matters in cold climates. I don't want the battery to shut down right when the weather gets worst.

Here's a nuance that saves people money: the backup battery doesn't need to run the whole building. It needs to run the essentials. For our 45-person office, that might be 10–20 kW of load, not the full 100 kW electrical panel. If you size the battery for 'stay open during a 12-hour outage' instead of 'live off-grid for a week,' the quote drops by a lot.

Scenario 3: EV fleet or employee charging is coming

If you're planning to add EV chargers, the solar system and the chargers should be designed together. Otherwise you'll end up with an electrical panel or transformer that can't handle the load, and the fix is more expensive than doing it right the first time.

Sunnova's EV charging offering is not an afterthought. You can get Level 2 chargers under the same service contract as the solar array, which simplifies my job: one contract, one invoice, one portal. At our company, we planned for six Level 2 chargers in the employee lot. We sized the solar array to cover charging from 7 a.m. to 6 p.m., and the battery is there to stop our site demand from spiking above the utility threshold. You may not need a large battery if your charging happens during solar production hours.

So, how much does the solar system cost?

I can't give you one number because there isn't one. But I can give you a range with a source, which is more than most websites do.

According to NREL's 2024 commercial PV cost benchmark, the median installed cost was around $2.30 per watt DC. I've seen small commercial quotes in our area run from $2.60 to $3.20 per watt depending on roof mounting and electrical work. That means a 50 kW system—about 125 to 135 panels—lands at roughly $130,000 to $160,000 before the 30% federal tax credit. After the credit, the net cash cost is about $91,000 to $112,000. Pricing as of January 2025; verify current rates because they move.

But most B2B customers I know don't pay cash. Sunnova's lease model lets you treat solar as an operating expense, which is a huge deal for a finance department that doesn't want a capital project on the books. I don't have access to Sunnova's current rate sheet—don't hold me to this—but in Q4 2024 I saw lease quotes around $0.10–$0.14 per kWh generated. That's a payment for production, not for panel count. Verify current lease pricing with Sunnova directly before you model your savings.

What if you're a smaller operation?

I'll be direct here: I've been a small buyer, and I remember which vendors treated a $400 order like a nuisance. That experience shapes how I run procurement today. Small doesn't mean unimportant—it means potential. A 20-panel commercial system might look tiny next to a warehouse project, but it's still a real system with real financial consequences. If a solar company acts like your order isn't worth their time, that's a signal about how they'll treat service calls later. Sunnova has treated our lease like any other account, and I won't take the small-business side for granted.

How to figure out which scenario you're in

Don't let a salesperson tell you. Spend 20 minutes with your last 12 utility bills and answer three questions:

1. If your peak demand happens between 9 a.m. and 5 p.m. on weekdays, you're likely Scenario 1.
2. If your business lost power for more than two hours in the last 18 months, you're Scenario 2.
3. If you have even one vehicle replacement planned in the next two years, you're Scenario 3.

If you're in two scenarios, combine them—but start with the one that costs you money when it fails. For a restaurant with cold storage, that's Scenario 2. For an office with no perishable inventory, it's Scenario 1. For a delivery company, it's Scenario 3. Once you know your scenario, ask Sunnova or a local installer for a design built around that scenario, not a one-size-fits-all quote.

My experience is based on one 45-person engineering services company with a flat roof and predictable demand. If you're a 500-person manufacturer with a 24/7 process load, you need an engineer to check the demand profile before you commit. But the decision diagram above should still help you identify the right questions—and that's the part most solar content skips.