Detroit-based DTE Energy said it will invest about $1bn on adding two scrubbers and a selective catalytic reduction (SCR) system at its Monroe Power Plant in Michigan, US.

The Monroe Power Plant has four generating units and is equipped with two scrubbers (flue gas desulfurisation units) and three SCRs.

The addition of two scrubbers is estimated to entail an investment of $600m and is expected to reduce SO2 emissions by 97%.

The construction work will begin in the first quarter of 2010.

The installation of the fourth SCR at a cost of $330m is aimed at reducing NO2 emissions by about 90%.

Work on the fourth SCR is scheduled for 2011.