Is Solar Power a Good Investment? How to Calculate Your ROI
May 9, 2026How Many Solar Panels Does Your Home Need?
May 9, 2026Yes — for most NJ homeowners, a properly sized solar system can cover 100% of annual electricity consumption. The key word is “annual.” Solar produces more in summer and less in winter, but net metering balances it out over the year.
How Net Metering Makes It Work
On sunny days your panels produce more than you use. That excess goes to the grid and your utility credits your account. On cloudy days or at night, you draw from the grid and use those credits. At the end of the year, your net bill can be near zero.
In New Jersey, net metering works at full retail rate — the credit you get for exported solar equals the rate you pay when you draw power. PSE&G, JCP&L, and Atlantic City Electric all offer this. Credits roll over month to month. At your 12-month true-up, surplus credits get purchased back at a lower avoided-cost rate — which is why it’s better to size your system close to 100% of your usage rather than significantly over it.
Sizing for 100% Coverage
Start with your annual kWh usage from 12 months of utility bills. Divide by 1,100–1,200 (NJ average production per kW of solar installed per year). That gives you the system size in kW you need. A home using 12,000 kWh/year needs roughly a 10–11 kW system.
Here’s what that looks like for typical NJ homes. A 1,800 square foot colonial in Marlboro averaging $180/month on PSE&G — that’s probably 10,500–11,000 kWh/year. You’re looking at a 9–10 kW system, somewhere around 21–23 panels at 440W. A 2,400 square foot home in Toms River with one EV charging overnight adds roughly 3,500–4,500 kWh to the annual load — now you’re designing a 13–14 kW system. A larger home in Hamilton with a pool in the backyard can run 16,000–18,000 kWh/year. At that point you’re looking at 14–16 kW, which may mean east/west arrays to fit it all on the roof.
What About High-Usage Homes?
If you have a pool, EV, or electric heat pump, your usage is higher than average. That’s fine — you just need a larger system. EV owners typically add 3,000–5,000 kWh/year depending on miles driven and charging level. Design the system around your actual usage, not a neighbor’s.
One thing that trips a lot of homeowners up: if you’re planning to add an EV in the next couple of years, size the system for it now. Adding 4 more panels to an existing system costs $3,500–$5,000 because you’re paying for another permit, engineering review, and interconnection update. Adding those same 4 panels in the original design costs $1,400–$1,800. The math is obvious — plan ahead.
Do You Need a Battery?
Not for bill coverage. With full net metering you can reach near-zero annual bills without any storage. A battery is a different decision — it’s about backup power during outages, not about whether solar covers your bill. The most common setup for NJ homeowners who want to eliminate their electric bill is grid-tied solar without battery. A battery gets added later if outage resilience becomes a priority, or if NJ’s net metering policy changes and self-consumption becomes more valuable.
NJ Seasonal Production — What to Actually Expect
Solar production in New Jersey isn’t even across the year, and understanding the pattern helps you understand how net metering works in practice. In summer (June through August), long days and high sun angle mean your system is running at 120–140% of its monthly average. You’re probably exporting a significant amount to the grid every day and building up credits fast. Spring and fall are close to average. January and February are the rough months — production drops to 50–60% of the monthly average because of short days, low sun angle, cloud cover, and occasionally a week of snow cover.
Net metering smooths this out because the summer surplus builds credits that carry you through January and February. When Jon runs a 25-year savings estimate for an NJ homeowner, he models this seasonal profile explicitly — not just an annual average — so you can see what your bill looks like in each month, not just the annual total.
What Limits Full Coverage
Roof size, shading, or HOA restrictions sometimes limit how many panels you can install. If you can’t fit enough panels for 100% coverage, a partial system still makes strong financial sense — you’re offsetting a portion of your bill, and the SREC income doesn’t care whether you hit 100% or 70%. Even a 6 kW system on a constrained or partially shaded roof with a payback of 8–9 years in NJ is a solid financial return.
On HOAs: New Jersey’s Solar Access Law protects homeowners’ right to install solar even in HOA communities. An HOA can regulate aesthetics but cannot prohibit solar outright or impose requirements that effectively make it impossible. If your HOA has been difficult about this, the law is on your side — and a good NJ solar contractor knows how to navigate it.
What About Adding an EV to the Mix?
This is one of the most common questions Jon gets from NJ homeowners right now. The short answer: if you’re adding an EV within the next few years, size your solar system for it today. Don’t size for your current usage and plan to add panels later.
The math on EV charging depends on the vehicle and your driving habits. A typical EV in NJ driving 12,000 miles per year needs roughly 3,000–4,000 kWh of electricity annually for charging. At $0.20/kWh from the grid, that’s $600–$800/year in charging costs — or roughly $15,000–$20,000 over 25 years. Add a properly sized solar system now, and most of that charging happens on solar power. The incremental cost of 3–4 extra panels to cover EV charging is $1,000–$1,600 in the original design. It makes no sense to not include them if an EV is on your horizon.
The Year-End True-Up: What Actually Happens
New Jersey’s net metering works on an annual cycle. Throughout the year, you build up credits when your solar produces more than you use (especially in summer), and you draw from those credits when production is low (especially in winter). The 12-month cycle resets on your anniversary date with your utility.
If you have a credit balance at the end of your annual cycle, your utility buys back the surplus at the avoided-cost rate — which is lower than the retail rate you pay for power. This is why Jon recommends sizing systems close to 100% of your annual usage rather than oversizing. A system that produces 115% of your usage sends 15% of its output to the grid at below-retail rates. That 15% is better used in your home at full retail value. The closer your system is to your actual annual usage, the less production goes to waste at below-retail compensation.
Pool Owners: What You Need to Know
A pool is one of the biggest electricity loads a NJ home can have. An in-ground pool pump running 8 hours a day during the summer season uses 2,000–4,000 kWh over the pool season — and that usage is concentrated in the exact months when your solar production is at its peak. That alignment is good: summer solar production matches summer pool pump load. If you have a pool, make sure your installer specifically accounts for pool usage in the annual kWh total they’re sizing the system for. And if you’re considering upgrading to a variable-speed pool pump — which uses 70–80% less electricity than a single-speed pump — do that before sizing your solar system, so you’re not over-building for a load you’re about to reduce.
How NJ Homeowners Approach the Decision
Jon talks to NJ homeowners at every point in the solar evaluation process. The ones who end up happiest with their systems share a few things in common. They pulled their actual 12-month usage before the first sales visit. They got three quotes. They didn’t sign with the company that called back fastest. They asked about SREC registration specifically. And they sized the system for where they’re going — an EV coming in the next couple years, maybe a heat pump — not just where they are today. None of this is complicated. It’s just a matter of taking the time to make an informed decision rather than a convenient one.
Find Out What Solar Saves You in Your Home
Every home is different — roof angle, usage, utility rate, and local incentives all affect your numbers. Enter your monthly electric bill below for a free savings estimate. Jon reviews every submission personally and follows up within 2 hours.
Find Out If Your NJ Home Can Go 100% Solar
The answer depends on your roof area, sun exposure, and annual usage. Jon assesses every home for free — roof condition, shading analysis, system sizing — and gives you a specific percentage before you decide anything. Book a free call to get your home’s honest assessment.
