How ecoligo calculates the CO2 savings of projects

Installation of solar panels at Kim Duc

At ecoligo, we’re proud of the fact that by investing into our solar projects, crowdinvestors can save tonnes of CO2 emissions. But how do we know how much? We explain our methodology below.

For grid-connected solar projects, we take into account various factors: the saved grid electricity1 and grid emission factor (GEF)2 of the respective country, the size of the solar plant and the specific yield of the plant, and the project lifetime3 , which we always set at 20 years.

The CO2 savings are calculated based on the following formulas:

saved grid electricity (MWh/a) = specific annual energy yield (kWh/kWp/a) * system size (kWp)

annual CO2 savings (t CO2/a) = grid efficiency factor (GEF) (t CO2/MWh) * saved grid electricity (MWh/a)

CO2 savings over the entire project lifetime (t CO2) = t CO2/ a * project lifetime (a)

Based on the CO2 savings over the entire lifetime, the project costs can be used to calculate the amount of CO2 saved per euro invested:

annual CO2 savings per 1 € invested (tCO2/€/a) = tCO2/ a / project costs (€)

For the project lifetime, the savings per euro invested can now be calculated over the entire project lifetime:

CO2 savings over the entire project lifetime (tCO2) = annual CO2 savings per 1 € invested (tCO2/€/a) * project lifetime (a)

For a specific investment, the personal CO2 savings can be calculated by multiplying the amount of the investment by the annual CO2 savings per € invested. It should also be taken into consideration that an investment has a loan tenor:

personal CO2 savings per investment (tCO2) =  (tCO2/€/a) per 1 € invested * amount of investment (€) * loan tenor (a)


The CO2 savings for the PV project Zena Roses are calculated as follows:

Calculation of CO2 savings

This calculation illustrates the positive impact that crowdinvestors create when investing via ecoligo. If you have any further questions on this topic, please contact us at

Do you want to make a difference with your investments, too? Then take a look at all our open projects today!

1 Saved grid electricity refers to the total grid electricity savings by the PV system aka total generation of the system in MWh per year. This is calculated by multiplying two factors: System size in kWp and specific yield in kWh/kWp.
2 Grid Emission Factor refers to CO2 emission factor (tCO2/MWh) which will be associated with each unit of electricity provided by an electricity system. It is a parameter to determine the baseline emissions for CDM projects in the renewable energy sector (hydro, wind, solar PV, and geothermal power, etc.) and waste heat/gas recovery sector. ecoligo uses CM (Combined Margin), which is the result of a weighted average of two emission factors pertaining to the electricity system: the “operating margin” (OM) and the “build margin” (BM). For more information see here.
3 Project lifetime refers to the technical lifetime of the solar system. This is independent of the contractual term between ecoligo and the customer. The solar system will function well beyond the 20 years, but it will only produce approx. 80% of its original output after 20 years.