The choice of fuel for the new plant at the Delimara power station is facing mounting criticism for contradicting government commitments to improve air quality.
Six environmental organisations as well as energy expert Edward Mallia reacted negatively to the government's announcement that the planned extension to the plant will operate on heavy fuel oil.
Prof. Mallia told The Sunday Times: "This is certainly not a step forward and cannot be described as progressive. One is going to have to deal with around 40 to 45 tonnes a day of waste, part of which will involve the removal of sulphur dioxide."
Sulphur dioxide causes a variety of health and environmental effects, and particularly affects the respiratory system and the heart.
But the ministry said yesterday that filters would be installed to capture the waste: "It is an illusion to think there can be any fire without smoke... our old plant emits these particles in the atmosphere with every unit of electricity we consume. The new plant is designed to capture it and store it."
The stored waste will be exported. Asked whether costs had been calculated, the ministry quoted a "very high estimate" of €420 per cubic metre.
The ministry failed to answer questions over whether any studies had been conducted on the potential impact on health of the new plant.
The existing power plant in the south has a history of controversy for operating without the use of filters and for the government's lack of published data on the monitoring of emissions, a fact the EU has drawn attention to.
The Marsaxlokk council had made calls on behalf of residents for the government to publish this data because of concerns over a rise in different forms of cancer in the south of Malta.
Speaking in Parliament last month, Labour MP George Vella said the medical profession could not explain the increase in cancers but believed it was linked to the power plant.
Prof. Mallia said: "Since we joined the EU, we were supposed to constantly monitor emissions. This has not been done. Now, the filters being mentioned will be installed on the new chimneys, not the old one. So the existing problem will remain."
The planned extension to the Delimara power station would require the construction of two new 65-metre high chimneys, in addition to the existing infrastructure.
Din L-Art Ħelwa and Nature Trust reminded the government of Malta's obligation to reduce emissions by 10 per cent by 2020, saying "any new investments in energy technology should aim for such reductions".
The ministry countered that Malta's commitment to reduce emissions was a legal obligation and not a political statement, and it would achieve this through an energy mix.
Friends of the Earth Malta, Gaia Foundation, Flimkien Għal Ambjent Aħjar and the Ramblers Association insisted: "It is unacceptable that newly commissioned turbines would once again run on fuels that produce greater toxic emissions."