HomeAlmost every solar conversation in New York City eventually arrives at the same question, usually phrased as “so what happens to the extra?” The answer is net metering, and it is worth understanding in some detail, because it determines most of the savings and because the bill it produces confuses people the first time they see one.
The basic mechanic
Your solar array and your building’s consumption are not synchronized. On a clear day in June the panels produce most heavily in the early afternoon, when a typical household is using very little. At seven in the evening the pattern reverses.
Net metering resolves that mismatch with a meter that runs in both directions. When the array produces more than the building is consuming, the surplus flows out to the grid and Con Edison credits your account. When the building needs more than the array is making — at night, or in December — you draw from the grid and pay for it as usual.
For residential systems in Con Edison territory, the credit is one-to-one at the full retail rate. A kilowatt-hour you export is worth the same as a kilowatt-hour you would have bought. This is the arrangement solar economics in New York City rests on, and it is more generous than what several other states now offer new customers.
What happens to credits you do not use
Credits do not expire at the end of each month. If July’s production exceeds July’s consumption, the surplus rolls forward and sits on the account against future months.
That rollover is the mechanism that makes a New York system work across seasons. A properly sized array in Brooklyn will overproduce from roughly April through September and underproduce from November through February. The summer surplus is what covers the winter shortfall. This is why judging your system on a single month’s bill tells you very little — you have to look at a full twelve months to see whether the sizing was right.
It is also why oversizing has diminishing returns. Banking credits you never consume is not the same as saving money, so a system meaningfully larger than your annual usage is generally building surplus you will not convert into value.
Why your bill never reaches zero
This is the most common surprise, and it is not a sign that anything is wrong.
A Con Edison bill separates supply — the electricity itself — from delivery, plus fixed charges that apply because you are connected to the grid at all. Net metering credits offset consumption. They do not eliminate the basic service charge, and they do not eliminate the fact that you are still a Con Edison customer using the grid as a battery.
On top of that, net-metered solar customers pay a monthly Customer Benefit Contribution, usually just called the CBC. It is calculated from the DC size of your system, so it is a fixed and predictable monthly amount rather than something that varies with production. It is modest relative to what a working system saves, and it is worth having your installer put the actual figure for your system size in the proposal rather than leaving it as a footnote. It is not a reason to skip solar; it is a reason your bill lands somewhere above zero rather than at it.
So the realistic outcome for a well-sized residential system is not “no electric bill.” It is a bill reduced to fixed charges and the CBC across most of the year, with the supply portion largely or entirely offset.
The twenty-year lock, and why the timing matters
New York has been moving distributed generation toward a different compensation framework — the Value of Distributed Energy Resources, or Value Stack, which pays exported energy according to when and where it is delivered rather than at a flat retail rate. For large commercial and community solar projects, Value Stack is already the standard.
For residential customers, one-to-one net metering remains the default offering, and customers interconnecting now are locked into it for twenty years. Value Stack is available to opt into, but it is not imposed on a residential rooftop system.
That twenty-year lock is the part worth weighing, because it is a hedge on two things moving in the same direction. Con Edison rates have risen substantially over the past decade and there is no serious forecast of them falling. Meanwhile, the general trajectory of net metering policy across the country has been toward less generous compensation for new customers, not more. Locking one-to-one retail credit for twenty years is a bet that grid electricity gets more expensive and that new solar customers get worse terms — both of which have been reliably true so far.
Getting interconnected
Net metering does not begin when the panels are bolted down. It begins when Con Edison grants permission to operate, and that is a separate process from the physical installation and from Department of Buildings sign-off.
In broad strokes: the interconnection application goes in during design, Con Edison reviews the system against the capacity of the local distribution network, the installation and DOB inspection happen, and then Con Edison authorizes the meter change and permission to operate. The array does not legally produce for your benefit until that last step.
The realistic timeline is driven by the utility and the City, not by the roof work. The installation itself is usually one to three days on a typical NYC home. The paperwork around it is measured in weeks to a couple of months, and it varies with how loaded your particular feeder is. Any installer who quotes you a same-week switch-on is describing the racking, not the process.
Two things genuinely slow projects down and are worth asking about: whether your service is adequate for the interconnection without a service upgrade, and whether your neighborhood’s distribution capacity is constrained. Both are knowable early, and finding out in month three is much worse than finding out in week one.
Reading your first post-solar bill
When the first bill arrives, four things are worth locating before concluding anything:
- Kilowatt-hours delivered — what you drew from the grid.
- Kilowatt-hours received — what you exported.
- The credit balance carried forward — the bank you are building for winter.
- The CBC line and the basic service charge — your floor.
If exports look low in a summer month, the usual explanations are ordinary: new shading, a soiled array, or an inverter fault that has not been noticed because nothing in the house behaves differently when a system underperforms. That last point is worth sitting with — a solar array can fail quietly for months, and the only symptom is a bill that is higher than it should be. Checking production monthly against the same month last year takes a minute and is the whole of solar maintenance for most owners.
If you want a specific answer for your building rather than a general one, the useful inputs are twelve months of Con Edison bills and your roof dimensions. That is enough to size an array against your actual usage pattern and to say what the bill would realistically look like afterward, CBC included. Send those over and we will work it out.