Solar Energy in Tamuning
Tamuning is located at 13.5°N, 144.8°E in Guam. Here's what solar energy looks like for homeowners in this area.
Annual Irradiance
1,945
kWh/m²
Peak Sun Hours
4.6
hrs/day
2.5 kWp Output
4,183
kWh/year
Solar Score
88
/ 100
What does this mean for your roof?
Tamuning receives approximately 1,945 kWh/m² of solar irradiance per year, which translates to 4.6 peak sun hours per day. This is excellent for residential solar energy production.
With a solar score of 88/100, Tamuning ranks #4 of 21 cities in Guam for solar potential in our atlas.
A typical 2.5 kWp residential solar system (6 panels) in Tamuning would produce approximately 4,183 kWh per year, sized for the average household in Guam.
The best months for solar production in Tamuning are Year-round (minimal seasonal variation), while the lowest production occurs during Rainy season (varies by region). Being in the northern hemisphere, south-facing roofs capture the most annual sunlight.
Estimated savings in Tamuning
System Cost
$3,250
2.5 kWp, before incentives
Annual Savings
~$464
At $0.188/kWh
Payback Period
~7 years
Before local incentives
25-Year Net Result
~$11,575
Savings minus system cost
These are approximate figures based on a standardized household consumption of 5,000 kWh/year and an estimated electricity rate of $0.188/kWh in Guam. Local incentives may reduce the upfront cost — check current subsidy, tax-credit, or VAT programs in Guam, as these can meaningfully shorten the payback period.
Figures are estimates based on typical system assumptions and the latest available electricity-price and billing data for Guam. Actual costs, tariffs, net-metering rules, and incentives vary by utility and change over time — confirm with a local installer or energy authority before making decisions.
How solar billing works in Guam
Exports and imports are priced separately, usually at different rates.
In Guam, rooftop solar appears to fall under a net-billing-style approach, where the energy you export and the energy you import are typically valued separately rather than simply cancelling out. Exports are often credited at a rate that may be lower than the retail price you pay for imported power, which generally rewards using your own generation as it is produced. The precise export and import prices vary by region and utility and change over time, so they should be confirmed locally.
Get your exact numbers
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Solar tips for Tamuning homeowners
Face panels south
In the northern hemisphere, south-facing panels capture the most annual sunlight. East-west split systems also work well.
Optimal tilt angle
For Tamuning, the energy-optimal panel tilt is about 14° from horizontal.
Size your system right
For the average household in Guam, a 2.5 kWp system (6 panels) covers most electricity needs. Use our calculator for a personalized estimate.
Check local incentives
Local incentives may reduce the upfront cost of residential solar — check current subsidy, tax-credit, and VAT programs with your energy authority in Guam.
Gear to prepare for solar
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Solar in other Guam cities
Frequently asked questions about solar in Tamuning
How much do solar panels cost in Tamuning?
A typical 2.5 kWp residential solar system in Tamuning, Guam costs approximately $3,250 before incentives — this is an estimate based on typical regional pricing. Local incentives such as subsidies, tax credits, or VAT exemptions may reduce the upfront cost; check current programs in Guam.
How are solar exports valued under net billing in Guam?
Under a net-billing-style scheme, exports from your system in Guam are typically bought at one rate while the electricity you import is charged at another, and the two are usually not the same. Because the export credit may be lower than the retail import price, consuming your own solar power directly tends to be the most valuable option. Actual rates vary by region and utility and can change, so confirm the current figures with a local installer or energy authority.
How much electricity do solar panels produce in Tamuning?
A 2.5 kWp solar system in Tamuning produces approximately 4,183 kWh per year, based on 4.6 peak sun hours per day and 1,945 kWh/m² annual irradiance.
What is the solar panel payback period in Tamuning?
Based on Guam's electricity rate of $0.188/kWh, a 2.5 kWp system in Tamuning pays for itself in approximately 7 years before incentives. After that, the electricity it generates is essentially free for the remaining panel lifespan of 25+ years.
Which direction should solar panels face in Tamuning?
In Tamuning, panels should ideally face south since it's in the northern hemisphere. The optimal tilt angle is about 14° from horizontal.
How many solar panels do I need for my home in Tamuning?
A typical household in Guam uses the equivalent of a 2.5 kWp system (6 panels). With 4.6 peak sun hours per day in Tamuning, this covers most electricity needs. Use our calculator for a personalized estimate.