How we calculate impact

NIB reports on the aggregated impact on productivity and the environment for different project categories, pro-rated to NIB's share of financing.

General principles

Impacts of financed projects are estimated ex-ante according to a set of environmental and other sector-specific indicators and in line with the Harmonized Framework for Impact Reporting agreed with other International Financial Institutions (IFI’s) under the Green Bond Principles. NIB finances projects in various stages of completion, therefore the ex-ante impact reflects information available to NIB at the time of the agreed loan. NIB bases the ex-ante impact estimates on the information provided by the client and on information available to NIB in official public data sources.

When possible, the data provided by the client is benchmarked to similar NIB financed projects and verified using relevant sources. If the initial data provided to NIB is expressed as a range of estimate, the conservative end of the range is used for the purpose of impact reporting. The ex-ante impact estimates are not updated during the project execution or after completion. For projects in which it is not possible to come-up with meaningful impact estimate, the impacts are not reported.

NIB reports reduced emissions based on direct reductions within the project financed, or alternatively indirect emission reductions in comparison with a baseline/alternative reference scenario. Should a project partly replace existing capacity or directly impact on the operation of other production units, only the difference in impact is reported as new capacity. Alternatively, rehabilitated capacity numbers are reported.

Aggregated impacts are pro-rated to NIB’s share of financing, i.e. disbursed loan amount divided by the total project cost.

Limitations and exceptions

There are categories of projects/investments for which this impact reporting methodology does not apply and where a more limited set of impacts are reported if any. These categories include e.g. the lending green bond purchase programme, and response loans.

Projects financed by NIB Environmental Bond (NEB) proceeds are reported on project-specific impact by NEB category.

Estimates for the installed capacity and energy generation are provided by clients and/or are based on public documentation (for instance, permit documents, online data etc.). For intermittent renewable energy generation (e.g. wind power, solar power), the P90 estimate is used when possible to mitigate uncertainty on the final generation and related climate impact.

Changes in energy use are estimated based on comparison of before and after investment, or if available using relevant baselines/alternative reference scenarios.

Greenhouse gas calculations are based on the Harmonized Approach to Greenhouse Gas Accounting, agreed with other IFI’s and coordinated by UNFCCC[1]. The EU grid emission factor for electricity, calculated as a combined margin (combination of built and operating margin), is used. For thermal energy, emission factors for the regional district heating system are utilized for calculation of changes in emissions. Emission factors for regional district heating systems are usually readily available online, alternatively we obtain information via the client.

For comparison of added renewable energy with the average annual energy use in single-family houses, an assumption of 25 MWh/yr is applied. This assumption is conservative and based on different statistics for the Nordics[2]. Comparison of greenhouse gas savings with the carbon footprint per capita are based on Eurostat on “Greenhouse gases (CO2, N2O and CH4 in CO2 equivalent)” for the NIB member countries[3].


[2] Assuming 120 m2 older house with electric heating and 4 residents.,¸  

[3] Statistics | Eurostat ( – air emission accounts by NACE Rev. 2 activity [ENV_AC_AINAH_R2], weighted-averages; average of 2018-2020; Impacts reported before 2021 – average of 2014-2016

Impacts describing the investments into electricity networks are expressed as kilometres of networks. This information is usually provided by the clients and for larger projects can be validated in public documentation (for instance, environmental impact assessments and permits). The number includes both distribution and transmission networks including overhead lines and underground cables. Both extension and replacement of existing cables is accounted for.

Renewable energy connected to the grid is expressed as connected capacity (MW), or where feasible, as volume of transmitted energy (GWh/a). Greenhouse gas savings are reported only for projects where energy is saved or recovered directly within the system as such, not for indirect benefits arising from transmitted renewable energy.

Estimates for changes in transportation modes are expressed as transport kilometres for persons or tons of freight and the associated greenhouse gas savings assuming that equivalent fossil fuel-based transports are replaced. The transport estimates are based on modelling conducted by the client. To validate client data and/or when client data is not available, NIB uses the Network for Transport Measures database[4], or equivalent data sources for estimating greenhouse gas savings.

Impacts for financed road infrastructure projects are expressed in kilometres of roads built/renewed. The length of the road is not adjusted based on the number of lanes or the type of the road. Therefore, the impact number includes various types of roads – from light traffic roads in smaller towns to high intensity highways connecting large cities.


Main indicator for wastewater projects is the added or upgraded treatment capacity presented as population equivalents (PE). One PE approximately equals the pollution load in household sewage produced by one person. The value of one PE is in general expressed as biochemical oxygen demand is 60-70 grams of oxygen per day (BOD5 or BOD7), depending on the applicable national standards for wastewater treatment. PE can also be based on the load of nutrients (phosphorus and nitrogen), when specifically targeting reduction of nutrient pollution (for instance, in case of industrial loads). When connecting new households to centralized wastewater treatment, the number of PE’s are estimated based on number of persons connected. Projects include expansion of existing wastewater treatment capacity or replacement of less efficient wastewater treatment solutions, e.g. by connection of households to centralized plants or refurbishment of wastewater treatment.

Reduction of nutrient discharges due to upgraded wastewater treatment are based on comparison of nutrient load before and after investment, taking into account changes in treated wastewater flow and treatment efficiency.

Data on treatment capacity and incoming/outgoing pollutant load are provided by the client and documentation connected to the project, such as Environmental Impact Assessments (EIA’s), feasibility studies and environmental permitting.

Indicators for buildings include gross floor area constructed, certification level and progress, and estimates for own carbon-neutral energy generation (solar or geothermal). These are provided by the client based on technical planning documents available at the time of project assessment. In terms of green building certification, initial certification scorecards are usually reviewed to confirm that the set certification level is achievable. For new green buildings, NIB does not report energy savings compared to energy use levels in national building code.

Impacts describing the investments into healthcare infrastructure are expressed in number for persons affected by the infrastructure. When possible number of people living in the potential catchment area of the healthcare facilities is provided by the client. To validate client data and/or when client data is not available, data on people living in the catchment area is obtained from official public source (e.g. national statistical office).

Impact of education infrastructure is expressed in number of pupils/students affected by the investments into the infrastructure (pre-schools, kindergartens, schools, universities). The numbers for number of pupils/students are typically provided by the client. In larger projects, it is possible to validate the numbers according to public documentation like education infrastructure development plans. Separate numbers are aggregated for university students given the different channels and magnitude of impacts of university studies comparing to pre-school and primary education.

For R&D programmes only the total loan amount and the number of R&D programmes financed is reported.

For loans to SMEs and environmental projects through financial intermediaries only the total loan amount and the number of programmes financed is reported.

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