This report presents pool 1 “Energy and fuels” (EF) in the Swedish national nitrogen budget (NNB). The EF pool is divided into four sub-pools; Energy conversion (EC), Manufacturing industries and construction (IC), Transport (TR) and Other energy and fuels (OE).
The Swedish data presented in this report are for 2015 whenever possible. If data were not available for 2015, available information for the year closest to 2015 have been used. The data were collected from Swedish official statistics and reports and preferably from sources that will continue to be updated, to make it easier to evaluate possible changes in N budgets in the future.
Emissions of reactive nitrogen (Nr) to the atmosphere via various combustion processes have been quantified as they have been reported to international conventions (CLRTAP and UNFCCC) broken down by the codes used in those reports.
The largest emissions of Nr occur from transport (24.1 kt), followed by manufacturing and construction (6.7 kt), other energy and fuels (4.9 kt) and energy conversion (4.8 kt). The majority of reactive nitrogen emissions from this sector (> 90 percent) consists of NOx, and otherwise of N2O and NH3.
The import of primarily crude oil and of other oil-based fuels means a flow of N from the rest of the world to Sweden (53.5 kt). A fraction of this amount is converted to reactive forms and emitted to the atmosphere during combustion. The main part of the NOx that is emitted from fuel combustion is, however, formed when nitrogen in the air is oxidized during the combustion (thermal production of NOx) and does not originate from the N in the fuel. Remaining N in the crude oil and oil products is either removed from the fuel during cracking in refineries or converted to N2 during combustion. Development of combustion processes where NOx is not formed leads to lower emissions. Biofuels such as ethanol and biodiesel are produced from e.g. wheat and rapeseed. A large part of the nitrogen present in these crops will remain in the residual products after fuel production and can be used for animal feed. They do not result in any emissions of reactive nitrogen in this national nitrogen budget.
The national nitrogen budgets do not include international transport (shipping, aviation), so additional emissions of reactive nitrogen will need to be added if a global aggregation is to be made.
Göteborg: IVL Svenska Miljöinstitutet AB , 2023.