Trelawny solar guide

The Falmouth coast and the interior are different solar settings.

Trelawny’s coastal strip is stronger in the long-term model, while the karst hills and Cockpit Country side of the parish produce a more moderate result.

Local data guide · published 31 August 2026

Try a system size

What would that mean on a roof?

These figures estimate electricity from the panels, not money saved. A kWh is one unit of electricity on your bill; kW describes the panel system’s rated size. Your savings depend on when you use that electricity, whether you store it in a battery and whether you send any to JPS Jamaica.

Typical year

7,805 kWhabout 650 kWh per month on average

Middle half of locations

7,610–8,020 kWhDifferences between locations; your roof can change the result

Strongest month

March · 727 kWhLong-term average, not a forecast

Weakest month

November · 611 kWhAbout 16% below March

Colour map of modelled annual solar electricity output across Trelawny. — **Annual solar electricity across Trelawny**Each square is approximately 1 km. The stepped edge shows the source resolution rather than pretending the estimate is more precise.

About 1,470About 1,680 kWh/kWp

The parish is not one number

The north coast leads. The interior reduces the parish average.

The map shows stronger output along the coast around Falmouth, Duncans and nearby communities. It becomes lower and more variable farther inland toward steeper, more heavily vegetated terrain.

A coastal roof and an inland hillside roof may therefore need different expectations, attachment details and shade analysis even at the same system size.

Cells analysed: 1,106
Central geographic range: 1,522–1,604
Typical variation: About ±3%

Month by month

How does solar output change through the year?

March is strongest in the long-term model. November produces about 84% of that output, so the annual figure should not be treated as twelve identical months.

633Jan

632Feb

727Mar

682Apr

645May

634Jun

670Jul

671Aug

644Sep

641Oct

611Nov

616Dec

Estimated monthly generation in kWh for the selected system size. Hover, tap or focus a bar for its detailed value. The figures are long-term estimates, not a weather forecast.

View the monthly figures as a table

Month	Per installed kW	5 kW system
January	126.5 kWh	633 kWh
February	126.5 kWh	632 kWh
March	145.3 kWh	727 kWh
April	136.3 kWh	682 kWh
May	129.0 kWh	645 kWh
June	126.8 kWh	634 kWh
July	133.9 kWh	670 kWh
August	134.3 kWh	671 kWh
September	128.8 kWh	644 kWh
October	128.2 kWh	641 kWh
November	122.2 kWh	611 kWh
December	123.2 kWh	616 kWh

Before asking for quotes

Questions worth asking in Trelawny.

Does terrain shorten the solar day?Hills and vegetation can create morning or afternoon shade. Ask for an on-roof shade assessment covering the full year.
Is the site difficult to reach?Narrow roads and steep sites affect delivery, lifting and service visits. Those costs should appear before a deposit, not after installation starts.
Does coastal exposure change the specification?Around Falmouth and the north coast, confirm salt-mist suitability and compatible metals across the complete mounting system.
How will storm water be kept out?Every penetration through metal or concrete roofing needs a documented flashing or sealing method that remains serviceable.

Use the Jamaica panel and roof guide to test the mounting and equipment answers in a quotation.

Generation is not the bill

A 5 kW system making 650 kWh a month will not automatically erase the same-sized bill.

Timing decides value

Solar used in the home avoids the retail cost of a JPS Jamaica unit. Surplus sent through net billing receives a much lower export credit.

A battery moves energy

A battery can carry daytime generation into evening use and provide outage cover, but it does not make the panels generate more.

Your roof changes the result

Shade, direction, heat, dirt, cable losses and equipment choices move a real installation away from the parish benchmark. Use the panel guide to test those roof assumptions.

How we calculated this

Where do these estimates come from?

We use long-term sunshine data to estimate panel output across the parish. These are planning averages, not a forecast for your roof. Shade, roof direction and equipment can change the result.

See the data, calculation and source assumptions

We selected the 1,106 Global Solar Atlas PVOUT grid cells whose centres fall inside the Trelawny parish boundary, then calculated the annual mean, central 50% range and monthly means.

The source models a free-standing crystalline-silicon system at optimum fixed tilt. It is useful for parish comparison and early planning, not a guarantee for a particular roof.

Solar source: Global Solar Atlas 2.0 PVOUT
Source years: 1999–2018 long-term average
Spatial resolution: 30 arc-seconds, approximately 1 km
Calculation: Jamaica Solar Check parish aggregation

Solar data obtained from Global Solar Atlas 2.0, developed and operated by Solargis on behalf of the World Bank Group with ESMAP funding. Source data © 2019 Solargis, CC BY 4.0. Parish calculations and colour map are adaptations by Jamaica Solar Check; the source organisations do not endorse this site. Boundary geometry: geoBoundaries JAM ADM1, sourced from OpenStreetMap/Wambacher, CC BY-SA 2.0.