New York Solar Panel Performance Benchmarks

A 6kW solar system in New York produces between 6,900 and 8,200 kWh per year, depending on location within the state. New York City and Long Island average about 7,900 kWh for a 6kW system. The Hudson Valley runs around 7,600 kWh. Western New York (Buffalo, Rochester) produces the least in the state, roughly 7,000 kWh, due to persistent lake-effect cloud cover from Lake Erie and Lake Ontario. Eastern Long Island solar performance is similar to coastal New Jersey.

Monthly Production Benchmarks: New York 6kW Reference System

Expected monthly production for a south-facing, 30-degree tilt, 6kW system. Derived from pvlib simulation using Open-Meteo ERA5 historical weather data, New York City as the reference location.

Month	Expected Production (kWh)	Notes
January	296	Short days; urban shading common
February	406	Modest winter recovery
March	628	Spring ramp begins
April	806	Good shoulder production
May	918	Near-peak
June	972	Peak month
July	966	Slight humidity effect
August	910	Late summer taper
September	758	Fall onset
October	546	Significant seasonal decline
November	306	Winter approach
December	246	Lowest month
Annual Total	~7,758	NYC-area 6kW reference

(Source: pvlib physics modeling, Open-Meteo ERA5 weather data)

Annual Benchmarks by System Size and New York Region

System Size	New York City / Long Island	Hudson Valley	Capital Region (Albany)	Western NY (Buffalo/Rochester)	Southern Tier
4 kW	5,170	5,070	4,910	4,660	4,830
6 kW	7,760	7,610	7,360	6,990	7,250
8 kW	10,350	10,150	9,810	9,320	9,670
10 kW	12,930	12,680	12,260	11,650	12,080
12 kW	15,520	15,220	14,720	13,980	14,500

NYC/Long Island specific yield: ~1,293 kWh/kW/year. Hudson Valley: ~1,268. Capital Region: ~1,227. Western NY: ~1,165. Southern Tier: ~1,208.

(Source: pvlib physics modeling, Open-Meteo ERA5 weather data, 2015–2024 averages)

New York Climate Zones and Performance Ratio Targets

New York has more solar variation than most homeowners realize. Buffalo's lake-effect clouds create conditions more similar to the Pacific Northwest than to New York City. Performance ratios below 0.76 warrant investigation.

Climate Zone	Representative Area	Annual Specific Yield	Expected PR Range
NYC Metro and Long Island	New York City, Nassau, Suffolk	1,260–1,330 kWh/kW	0.78–0.86
Hudson Valley	Westchester, Dutchess, Orange, Ulster	1,230–1,310 kWh/kW	0.76–0.84
Capital Region	Albany, Schenectady, Troy	1,190–1,270 kWh/kW	0.74–0.82
Western NY	Buffalo, Rochester, Syracuse	1,120–1,220 kWh/kW	0.72–0.80
North Country	Watertown, Plattsburgh	1,110–1,200 kWh/kW	0.70–0.78

Learn more about how these benchmarks are calculated at /resources/methodology.

What Affects New York Solar Output

• Lake-effect clouds (Western NY): Buffalo and Rochester sit directly in the lake-effect snow and cloud belt from Lakes Erie and Ontario. From October through April, these areas receive 25–40% more cloud cover than New York City. A 6kW system in Buffalo producing 6,990 kWh/year is performing well for its location; comparing it to a NYC system is not valid.
• Urban shading (NYC): Dense urban construction creates rooftop shading from neighboring buildings, water towers, and mechanical equipment that doesn't exist in suburban or rural settings. NYC rooftop systems often have lower specific yield than the regional benchmark not because of weather but because site-specific shading reduces effective irradiance.
• Strong winter-summer seasonality: New York's latitude (40–45°N) produces a 4:1 ratio between June peak and December minimum output. This is physics, not a system problem. December producing 246 kWh and June producing 972 kWh for the same 6kW system is expected.
• Snow and ice: Unlike more southern states, New York systems lose production to snow accumulation November through March. Most losses clear naturally, but persistent flat-roof accumulation can block production for multiple days per event.
• NY-Sun incentive context: New York's NY-Sun initiative has driven significant residential solar installations statewide. Installation quality is generally high, meaning unexplained underperformance is more likely a specific site issue than a broad installation problem.

Frequently Asked Questions

Q: What should a 6kW solar system produce per month in New York City?

A: The NYC benchmark averages about 647 kWh/month. June peaks near 972 kWh; December drops to 246 kWh. The 4:1 seasonal ratio is normal. Consistent summer production below 780 kWh/month in June or July on a 6kW NYC system warrants investigation.

Q: Why does my Buffalo solar system produce so much less than a friend's system in Long Island?

A: Western NY systems average about 6,990 kWh/year for 6kW vs. 7,760 kWh/year on Long Island. The 11% difference is driven almost entirely by lake-effect cloud cover from October through April. Both systems performing at their regional benchmarks are healthy. The problem would be a Buffalo system producing at NYC benchmark levels; that would indicate a site issue, not regional weather.

Q: Does snow on my New York panels hurt production?

A: Snow accumulation reduces or eliminates production while panels are covered. New York receives 2–6 significant snow events per winter depending on location. Annual production impact ranges from 1–2% in NYC to 3–5% in Western NY. Snow clearing provides minimal economic return in most cases; the production loss is modest and snow typically slides off within a few days.

Q: How do I get an independent benchmark for my New York solar system?

A: A valid benchmark uses actual ERA5 hourly weather data at your address, critical in New York where lake-effect cloud cover creates significant local variation. Standard monitoring apps track only actual output. Learn more at /resources/methodology.

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Data: pvlib physics modeling + Open-Meteo ERA5 weather data | Last updated: 2026-04-06 | Solar Benchmark