References and Explanations
Lbs of CO2
per panel
The amount of electricity a panel can generate in a day is calculated by multiplying (1) the output of the panel (Watts) and (2) the number of hours of sunlight to which the panel is likely to be exposed (Hours). This results in the Watt-hours (Wh) the panel can produce, which is typically expressed in the thousands of Watt-hours or Kilowatt-hours (kWh). The quantity of CO2 avoided by generating the amount of power generated by a solar panel, is calculated by looking at the CO2 that would have been produced if the same electricity were generated on the regional power grid where the solar panel was installed. Estimates for this site were computed using the EPA, Greenhouse Gas Equivalencies Calculator.
In summary, the lbs of CO2 avoided per panel depends on the output of the panel, the sunlight in the area it was installed, and the amount of CO2 that the public utilities in the regional grid would have created if they generated that power.
The quantity of CO2 avoided per panel for a specific non-profit solar project can be found in the List of Solar Projects Accepting Donations.
Years in operation
One of the main benefits of donating a solar panel is that it functions as a "green endowment" helping reduce CO2 continually years after your donation. Most high-efficiency solar panels have a warranty from the manufacturer to continue producing electricity for at least 25 years. After that time a solar panel is likely to continue to produce electricity, but may do so with less efficiency. For example, some manufacturers state that after 30 years their solar panels may continue to produce 89% of the electricity that it produced during its first year. See Silfab SIL-430QD (25 year warranty; 89% after 30 years); QCell Q.Peak Duo BLK (25 year warranty; 86% after 25 years)
Lifetime CO2 reduction is estimated on this website by multiplying the annual CO2 reduction expected in the first year of a solar panel's operation by 25 years. Per the discussion above, the estimate may under-reflect actual CO2 avoidance as it does not account for continued electricity generated after the initial 25 year time period, and over-reflect actual CO2 avoidance as it does not account for degradation in efficiency. In addition, lifetime CO2 reduction assumes that the CO2 avoidance in a particular region does not change with time.
Equivalent number of trees planted
According to the Environmental Protection Agency (EPA), a medium growth tree planted in an urban area and allowed to grow for 10 years, will sequester an average of 36.4 lbs of CO2 per year. As a result, if a solar panel avoids 1,000 lbs of CO2 per year, that is the equivalent to the CO2 reduction capable of 27.47 trees (1,000 / 36.4). See EPA, Greenhouse Gas Equivalencies Calculations and References (using weighted average of CO2 emission between coniferous and deciduous trees).
The effect of donating a solar panel on CO2 reduction in the example above is likely greater than planting 27 trees, as trees must be mature (i.e., 10 years growth) in order to achieve the above-referenced level of CO2 reduction. When planting trees for the purpose of CO2 reduction, the "survival" rate of a seedling to reach the 10 year mark is approximately 59%. Id. As a result, you would need to plant approximately 46 trees, and wait 10 years for some of them to mature, in order to receive the same CO2 offset as a solar panel that can avoid 1,000 lbs of CO2 per year.
Average
carbon footprint
The average carbon footprint for a person in the United States is 16 metric tons (or 35,264 lbs). New Jersey Department of Environmental Protection, Climate Change (last viewed April 26, 2025). The amount of carbon that a person generates, however, depends on a variety of factors. The United States Environmental Protection Agency offers an online calculator to calculate your own carbon footprint. That calculator looks at personal energy consumption, vehicle usage, and trash. It does not account for airplane travel or food consumption.