Power plant reducing emissions and costs

ONE of the ESB’s biggest customers is to produce its own electricity.

The threatened ESB strike will not affect the Aughinish Alumina plant in the Shannon Estuary.

Until last year, it was the ESB’s single biggest customer.

The company’s monthly bill had topped €1 million but Aughinish now produces all its own power requirements.

A state-of-the-art €100m Combined Heat and Power (CHP) plant on site turns out 150 megawatts of electricity and is already proving a financial and environmental winner.

As the plant requires 40 megawatts to operate, Aughinish has a deal to sell off its 110-megawatt surplus to the ESB.

Aughinish, over the years, has withstood a barrage of criticism from environmentalists and local farmers’ groups who blame the company for alleged animal health problems.

A company spokesman said the new CHP plant will make Aughinish an environmental leader in Irish industry through a massive fall in carbon dioxide emissions.

The drop in CO2 emissions will play a big role in aiding Ireland achieve its Kyoto Protocol targets.

The CHP plant, fired by three gas turbines, provides Aughinish with energy savings of up to 25%.

It also cuts CO2 emissions by 150,000 tonnes a year.

Sean Garland, administrative manager at Aughinish, said: “The CHP plant is generating an economic return in its first year, which we are very happy with. We didn’t just make this investment for economic reasons — it was a factor but the CHP plant had also anumber of environmental drivers.”

Before the plant began operations, much of the Aughinish electricity came from the Tarbert Island ESB power station 15 miles down the Shannon Estuary.

The ESB station produces just over four times the output of the Aughinish CHP plant.

Traditional stations such as Tarbert have a thermal efficiency of about 33%, meaning two-thirds of the energy from the fuel oil burned at that station is wasted.

The Aughinish facility has a thermal efficiency of 55%. The efficiency increases further to 80% as the steam produced is not expelled into the atmosphere but harnessed for use in the manufacturing process.

Mr Garland said: “By capturing the heat from the electricity generation process on site, the CHP plant can provide us with energy savings of up to 25%.”

Due to a lack of indigenous natural gas, Aughinish imports its gas supply from Britain.

Companies in Britain pay a transport cost of one penny per unit, but to pump the gas by pipe to Aughinish the transport cost spirals to six pennies per unit.

The Aughinish gas bill for 2007 is expected to top €60m.

Mr Garland said the company will in the future be looking to the new gas supply from the Corrib field off the west coast to provide their needs — and major savings.

The Aughinish plant, the most modern of its kind in the world, ships in two million tonnes of bauxite ore every year from west Africa to manufacture one million tonnes of alumina. This is then shipped abroad to smelters, mostly in Scandinavia, where it is smelted into aluminium.

There are 500 permanent staff and 200 contractors employed on site and it is estimated that the plant it worth up to €100 million to the local economy.

Aughinish is owned by the Russian/Swiss corporation United Company Rusal, the world’s largest producer of aluminium and alumina.