System upgrades

Older system? Get more out of it.

Inverter swaps, panel additions, battery adds, and full repowers — for solar systems Teamsun installed and ones we did not. Aurora diagnostic first, quote second.

Get a free quote 203-903-4091

By the numbers

Diagnostic Aurora-modeled
Common upgrade Inverter swap
Project timeline 3 – 10 weeks
Equipment Tier 1 only

Signs it's time

Four signals your system needs attention.

Most older systems do not need full replacement — they need a targeted upgrade. We diagnose first, quote after.

Production has dropped

Compare this June against the June three years ago. Real production drops of 15%+ usually mean a dead optimizer, a failing inverter, or panel degradation beyond spec.

Inverter is at end-of-life

Most string inverters from 2010 – 2015 are nearing or past their 10 – 12 year warranty. Replacement cost is going up, not down — a swap now is often cheaper than reactive replacement at failure.

Warranty has expired

If your panels or inverter are out of warranty, a single failure can wipe out years of bill savings. We can extend coverage with new equipment under fresh warranty.

Roof needs more capacity

Added an EV, a heat pump, or just a couple more people in the house? Older systems were sized for old loads. We add panels, swap inverters, or add a battery to match your real demand.

Common upgrade paths

Four ways we upgrade.

Pick the right one based on what your roof and your real production data tell us. Most homes get the smallest upgrade that solves the actual problem.

Inverter swap

Replace a failing or end-of-life inverter with a modern Tier 1 unit. Most common upgrade — restores production and resets the warranty clock.

Panel addition

Add panels to an existing system if your roof and inverter capacity allow. Aurora model dictates exact placement.

Add a battery

Often the highest ROI upgrade — see our retrofit service. Eligible for the 30% federal ITC on the new battery cost.

Full repower

Strip and replace an aging system with modern Tier 1 panels and inverter. Reset all warranties, claim the federal ITC on the new system.

Our approach

Our process,
refined through
9,000 installs.

01.

Design

A 15-minute call, then a remote or on-site visit. Aurora-based design, panel and battery brand named on the proposal.

02.

Build

Permits filed, utility interconnection submitted, and equipment staged at our Bristol warehouse.

03.

Install

Local crew, local trucks. Most homes finished in 2 – 3 days. Final inspection scheduled before we leave.

04.

Perform

PTO from your utility, ITC and rebate paperwork filed, and 25 years of local service after the system goes live.

Your incentive stack

Federal, state, and utility
stacked.

On a typical $30K install in Connecticut, the total incentive stack lands between $13,000 and $17,000. We file every form with you.

Federal ITC

30%

Tax credit, claimed in the year of install. Locked through 2032.

CT ESS battery rebate

Up to $7,500

One-time check from CT Green Bank, paid through your installer.

Net metering

Full retail

1:1 offset on what your panels send back to Eversource or UI.

CT property tax exemption

$300 – $700/yr

System value excluded from your assessment. Sales tax also exempt.

Where we work

9,000+ rooftops across three states.

Connecticut, Massachusetts, and Rhode Island. Every pin is a Teamsun install. We're licensed in ME, NH, VT, and FL too.

CT · 5,400+ installs MA · 2,900+ installs RI · 700+ installs

Check your town

What customers say

Trusted by homeowners
who value quality.

“Teamsun was the only crew that walked the roof, named the panel brand, and answered every question without checking with someone. Same lead tech came back a year later when I added a battery.”

“Three of my neighbors had Teamsun, so I called them. The crew was on my street five days after I signed.”

“They knew the historic district secretary by first name. Saved us six weeks on permitting alone.”

“Same lead tech who installed it came back four years later to swap an inverter under warranty. No charge, no excuses.”

Upgrade FAQ

Questions homeowners ask about upgrades.

How do I know if my system is underperforming?

Pull the last three Junes from your monitoring app and compare. If production is down 15% or more year-over-year, something is wrong. If you do not have monitoring, we install temporary metering during the diagnostic visit.

Can I claim the federal ITC on an upgrade?

Only on the new eligible costs. The ITC applies to new equipment (panels, inverter, battery) and the labor to install it — not to the pre-existing system. Speak with your CPA; we file the paperwork to substantiate the new costs.

How much does an upgrade typically cost?

Inverter swaps run $3,000 – $7,000 depending on system size and brand. Panel additions run $1,200 – $1,800 per kW added. Full repowers run 80 – 90% of a fresh new install cost. Every quote is preceded by a diagnostic visit.

Will a new inverter give me higher production?

Sometimes. A failing inverter is silently de-rating your system; a healthy modern inverter will recover that loss. A modern inverter on an already-healthy system gives marginal production gains (1 – 3%) — we tell you which case yours is.

Can you upgrade a system from 2010 or earlier?

Yes. Vintage systems often need partial repowers because the original modules and inverters are no longer supported. We model the upgrade in Aurora using your actual roof and your real utility rate before quoting.

Do I need to upgrade if my system is still producing?

Not always. If production matches Aurora projections and your warranty is intact, leave it alone. We will not sell you an upgrade you do not need — see our maintenance and repair service for one-off fixes.

How long does an upgrade take?

Inverter swaps and battery adds take 1 – 2 days on-site, 3 – 6 weeks total project time. Panel additions take 1 – 2 days on-site, 4 – 8 weeks total. Full repowers run 6 – 10 weeks total.

Will an upgrade affect my net metering enrollment?

A like-for-like inverter swap usually does not. Adding panels or significantly increasing system size triggers a net metering re-enrollment with your utility. Teamsun files every form on your behalf.

Free quote

Ready to go solar?
Request a quote today.
It's free.

A 15-minute call with a designer who knows your town. No closer on the line. No follow-up unless you ask for one. $0 down options available.

Request a free quote 203-903-4091

Bristol office

A person picks up.
Mon – Fri, 8am – 6pm.

Service area

CT · MA · RI
Licensed in ME · NH · VT · FL

Free terms

$0 down, free consult.
No credit card required.