A Quality Inspector's Checklist for Sunnova Solar, Storage, and EV Charging

I review quality and brand compliance for a renewable energy company. Roughly 200 contracts and deliverables cross my desk every year. I have rejected first deliveries for issues as small as a mislabeled breaker and as large as a fundamentally wrong battery specification.

This checklist is for B2B buyers evaluating Sunnova solar leases, home energy storage products, or EV charging infrastructure. It is also for anyone asking the question I hear constantly: is solar generator worth it for my site? Use this after you receive a proposal, not after you sign. Five steps. Each step has one concrete check.

Step 1: Log In and Pull the Full Contract, Not the Portal Summary

Go to the Sunnova login page and access your customer account. Download the full contract PDF. The dashboard shows a summary. The contract shows obligations.

Check these items specifically:

• Service address and system size match the proposal.
• Lease payment and any annual escalation rate are written out.
• Buyout option price and timing.
• Who owns the SRECs, net metering credits, or other incentives.
• Transfer rules if you sell the property.

I once saw a lease with a 2.9% annual escalator buried on page 14. The sales summary said 'guaranteed monthly payment.' That was true for year one. Period.

Step 2: Read the Sunnova Solar Warranty Like a Spec, Not a Brochure

Ask for the actual warranty certificate. Do not rely on a marketing table. The Sunnova solar warranty covers different components for different lengths of time.

Confirm four things:

1. Panel product warranty: usually 25 years, but check the degradation guarantee in percent per year.
2. Inverter warranty: often 12 to 25 years, depending on the model. Ask whether replacement includes labor.
3. Battery warranty: confirm the throughput limit in kWh, not just the calendar term.
4. Roof penetration warranty: who pays if the installation causes a leak?

I don't have hard data on industry-wide claim rates. What I can say from our reviews is that exclusions matter more than coverage terms. A warranty that covers parts but not labor is common. That changes the true replacement cost. Read the 'what is not covered' table first.

Step 3: Compare Home Energy Storage Products by Usable Capacity, Not Sticker kWh

Sunnova uses lithium iron phosphate (LFP) chemistry for its battery storage. That is a positive from a thermal runaway perspective. But chemistry alone does not tell you if a system fits your load profile.

For any home energy storage product you evaluate:

• Usable capacity vs total capacity. LFP batteries often have usable capacity around 90 to 95 percent of rated.
• Continuous discharge power. A 10 kWh battery with only a 3 kW output cannot start a 5 kW motor.
• Round-trip efficiency. Look for rated efficiency in the mid-to-high 80s.
• Warranty throughput. A battery advertised for 10 years may only hold 70% capacity after a certain number of cycles.

Everything I read about storage said higher total capacity is always better. In practice, usable capacity and discharge power matter more. Compare usable kWh per dollar, not rated kWh.

Step 4: Separate EV Charger Government Grants from Tax Credits and Rebates

There is a difference between a grant, a tax credit, and a utility rebate. They have different deadlines, different eligibility, and different paperwork.

Start with the DSIRE database (dsireusa.org). It lists state-level incentives. Do not assume a federal program covers you. For example, the federal solar Investment Tax Credit under the Inflation Reduction Act is 30% for systems placed in service through 2032. That applies to solar and paired storage under certain conditions. EV charging infrastructure has a separate credit with separate caps. Verify current numbers on energy.gov.

Here's the thing: I have seen two businesses lose EV charger government grant funding because they purchased equipment before confirming eligibility. The incentive was announced. The order was placed. The paperwork missed a compliance requirement. Confirm first. Then purchase.

Step 5: Ask the Real Question: Is Solar Generator Worth It for Your Site?

The conventional wisdom says solar generators are overpriced. In practice, for sites with high outage costs, the calculation flips.

Run this three-way comparison:

1. Grid power only: baseline price per kWh, plus the cost of every outage hour.
2. Solar plus battery storage: upfront cost, usable capacity, outage coverage, tariff arbitrage value.
3. Solar generator: solar panels plus a portable power station. Lower installed cost, but no backup for high-load equipment unless sized correctly.

If your only metric is payback years, grid power usually wins. If downtime costs more than the annualized system cost, a solar generator or battery can pay for itself in one event. I wish I had tracked outage cost per site more carefully. Anecdotally, the sites that treat resilience as insurance are the ones that justify the purchase.

Mistakes I See in Almost Every First Review

These come up again and again:

• Comparing monthly lease payments without comparing price per kWh.
• Forgetting that most warranties exclude labor unless you buy a premium service contract.
• Not checking whether the battery's continuous discharge rating covers surge loads.
• Trusting a verbal promise about a Sunnova solar warranty update without a written revision.
• Letting a grant deadline rush the contract review.
• A communication mismatch is just as expensive. I said 'as soon as possible.' They heard 'whenever convenient.' Result: delivery two weeks late.

One more note: my experience is based on B2B installations with commercial off-takers. If you are a single-family homeowner, your lease terms, warranty language, and incentive calculations will differ.

Bottom line: this checklist won't tell you which option is cheapest. It will tell you which one is real. The vendor who lists all fees upfront—even if the total looks higher—usually costs less in the end.