Beräkning av emissioner från transportinfrasruktur
Low frequency noise (20 - 200 Hz) from combustion engines typically dominates the indoor sound environments and is a source for annoyance and sleep disturbance. This study investigated the impact on low frequency noise when diesel operated buses were replaced by electric buses along a bus line in Gothenburg, Sweden. Noise measurements were performed indoors and outdoors for a selection of apartments directly exposed to bus traffic as well as for reference apartments, before and after the intervention. In addition, noise levels were calculated. The results show a significant reduction of the indoor low frequency noise in the range 40 - 80 Hz in the apartments directly exposed to passing buses, both during bus passages (on average 10 dB), and in one-hour measurements (on average 5 dB). The results further show that A-weighted values fail to accurately represent the reduction in noise achieved by the intervention.
Environmental considerations, concerning the negative impacts of ship exhaust gases and particles on ambient air quality, are behind the requirements of cleaner marine fuels currently applied in designated emission control areas (ECAs). We investigated the impact of a ship operating on two types of fuel on the indoor air quality onboard. Gaseous and particulate air pollutants were measured in the engine room and the accommodation sections on-board an icebreaker operating first on Heavy Fuel Oil (HFO, 1%-S), and later Marine Diesel Oil (MDO, 0.1%-S). Statistically significant decrease of SO2, NOx, PM2.5 and particle number concentration were observed when the ship was operating on MDO. Due to the higher content of alkylated PAHs in MDO compared to HFO, the concentration of PAHs increased during operation on MDO. The particulate PAHs classified as carcinogens, were similar to or lower in the MDO campaign. Chemical analysis of PM2.5 revealed that the particles consisted mainly of organic carbon and sulfate, although the fraction of metals was quite large in particles from the engine room. Principal Component Analysis of all measured parameters showed a clear difference between HFO and MDO fuel on the indoor environmental quality on-board the ship. This empirical study poses a first example on how environmental policy-making impacts not only the primary target at a global level, but also brings unexpected localized benefits at workplace level. The study emphasizes the need of further investigations on the impact of new marine fuels and technologies on the indoor air environments on board.
In January 2020, new global regulations were implemented to limit the maximum sulphur content in marine fuels. As an alternative to switch to compliant fuels, the regulations allow for installations of exhaust gas cleaning systems, e.g. scrubbers, that enables a continued use of less expensive heavy fuel oils (HFOs).
Characterization of scrubber discharge water shows that the acidified water also becomes enriched with contaminants, and large quantities of metals and polyaromatic hydrocarbons (PAHs) are thus being discharged directly to the marine environment. When emissions of contaminants to the atmosphere and the marine environment are evaluated simultaneously, the results show that HFO, with scrubbers installed, generates higher emission factors of both metals and PAHs compared to MGO. This highlights the importance of including both the marine and the atmospheric perspective when comparing environmental loads and impact of contaminants from shipping.
Air pollution is the largest health risk from environmental causes, mainly driven by human exposure to fine particulate matter with aerodynamic diameter <2.5 µm (PM2.5). Emissions from combustion engines (including ship engines) contribute to PM2.5 in ambient air both with primary particles (black carbon), organic carbon, and other particles) and with secondary particles formed from exhaust gases – mainly nitrogen oxides (NOx) and sulphur oxides (SOX). NOx and SOx react with ammonia (NH3) in the atmosphere to form secondary inorganic aerosols, which have been shown to constitute ∼30–50% of PM2.5 levels in ambient air in northern and central European countries. We analyse the potential for emission reduction, emission control costs, and monetised benefits following the introduction of a NECA. Costs and benefits are compared for 2030. We compile new data on emission control costs for shipping, use the GAINS model for calculations of emission dispersion, and the Alpha-RiskPoll model for estimating monetary values of health impacts. The model results show that costs to conform to the NOX regulations of a NECA in the Baltic Sea, North Sea or both sea regions would be 111 (100–123), 181 (157–209), and 230 (195–273) million € per year, respectively. Corresponding benefits from reduced emissions are estimated to be 139 (56–294), 869 (335–1882), and 1007 (392–2177) million € per year, respectively. Calculated benefits surpass costs for most scenarios, but less convincingly for a Baltic Sea NECA. Conforming to the NECA regulations by using Liquefied Natural Gas (LNG) propulsion engines is estimated to give the highest net benefits but also the largest variation (costs: 153 (88–238), benefits: 1556 (49–3795) million €/year). The variations are mainly due to uncertainties in the valuation of avoided fatalities and climate impacts. It is concluded that the NECAs for the Baltic and North Seas can be justified using CBA under all but extreme assumptions.