The Corus steel plant in Port Talbot is Wales biggest CO2 emmitter
A £60m investment to reduce the "carbon footprint" of the huge Corus steelworks in Port Talbot has been completed.
The plant, which employs 5,000 people, is the largest carbon emitter in Wales, producing up to 7m tonnes of C02.
The steelworks is starting to recover by-product gas, which was formerly flared-off and recycle it as fuel.
The company estimates it will cut 240,000 tonnes per year from its carbon footprint and also reduce emissions of dust particles by 40 tonnes a year.
The steelworks' current demand for energy is about 140 Megawatts (MW), about half of which is internally generated. The company also has its own power station.
Corus, which already recovers process gas produced in the plant's coke ovens and the blast furnaces, has been building the technology at Port Talbot for two years.
GAS RECOVERY PROJECT
Up to 300 people worked on building the BOS Gas recovery system
The new gasholder uses 2,200 tonnes of steel
Nearly 3km of gas ductwork and 5km of other pipeline has been installed
Carbon emissions will reduce by 240 tonnes - or 3% of emissions from Port Talbot
The recovered gas will generate 10% of the plant's electricity needs
New owners Tata Steel were unhappy at what they saw was wasteful burning of excess gas, especially at a time of rising gas prices.
The investment is Port Talbot's largest since Corus was taken over in April 2007 and the company said it was the biggest single climate change investment in Wales.
There is similar technology at Corus plants at Scunthorpe and at IJmuiden in the Netherlands, as well as at Tata's plant at Jamshedpur in India.
Tata Steel Europe's chief executive Kirby Adams, said: "In order to be more competitive in the global steel market, this project had to be delivered."
Mr Adams called on the Welsh Assembly Government to work closely with the steel industry to create an environment in which further investment "becomes even more attractive".
He warned that more environmental regulation and targets were a burden which was costing the business.
He added: "The economic recovery is fragile and times are uncertain. But we have a long-term vision for sustainable steelmaking in Wales.
"Through this and other key investments, we have shown our commitment to growing our business in Wales."
First Minister Carwyn Jones, speaking at the launch, said it would be a "massive boost" to the Welsh economy.
He said ahead of Wales Sustainability Week next week, "it is a pleasure to be here in Port Talbot to launch this key investment by Corus, which is a big boost for sustainability in Wales".
Port Talbot has been producing steel for more than 100 years.
At its height in the 1960s, following the opening of the Abbey works, the plant employed more than 18,000 workers.