Southdowns was commissioned by Breathe Energy Limited to prepare an air quality assessment of the impacts associated with new plant for the heating system at St. Helier Hospital.
A detailed assessment of the operational impacts associated with three 5,800 kW Danks steam boilers and three Bosch UTM/16 boilers, a Combined Heat and Power unit and two Fulton VSRT15 steam generators was undertaken as part of this project.
ADMS-Roads dispersion modelling software was employed to predict the contribution of NO2 at local receptors, the main pollutant of concern for point-source gas-fired combustion sources.
It was found that the low-NOX boilers would have substantially lower emissions than the original ones, the new CHP would lead to an overall increase in on-site NOX emissions.
The assessment showed that the proposed plant would nevertheless result in negligible air quality impacts at on- and off-site receptors.
The assessment incorporated embedded mitigation within the energy plant scheme by ensuring a minimum flue stack height to minimise impacts on local air quality at ground level.