The ESB is likely to be the first company where Government pay policy is challenged this winter. The ESB Officials' Association has just served strike notice on the company in support of a 16.5 per cent pay claim.
Other unions in the company are likely to back the ESBOA if it takes industrial action.
Meanwhile, two major public service unions, IMPACT and the Irish Nurses' Organisation, have decided to seek extra pay and tax concessions. IMPACT has not put a figure on its claim but says it must be sufficient to protect workers' living standards from inflation.
The INO is seeking 5 per cent, in line with the guideline figure set by SIPTU earlier this week. It also wants the benchmarking process bringing public-service pay rates into line with the private sector brought forward by 18 months to the beginning of 2001.
With SIPTU, IMPACT, the INO, ATGWU and teachers' unions all committed to a pay review of the Programme for Prosperity and Fairness, the outcome of next week's executive meeting of the Irish Congress of Trade Unions is a foregone conclusion.
But the ESBOA claim now seems likely to present the Government with its first major challenge.
The confrontation is particularly fraught because the ESB group of unions is in the middle of restructuring talks.
The company wants 2,000 redundancies and radical changes in work practices without conceding any pay rise. Rising fuel costs and the Government price freeze on electricity leave little room for manoeuvre.
The ESBOA put in its claim last June and gave the company until Wednesday to make a "serious offer". The union's general secretary, Mr Willie Cremins, confirmed yesterday that 30 days' notice had now been served for industrial action.
Traditionally the ESBOA, which represents white-collar workers in the company, has been regarded as a conservative union, but Mr Cremins said members had voted by 84 per cent for strike action. "It's my belief that management is seriously underestimating their strength of resolve," he added.
Resentment was fuelled by the large pay increases to groups such as nurses and construction workers, as well as rises for senior staff within the ESB.
The secretary of the largest ESB union, Mr Denis Rohan of the Amalgamated Transport and General Workers' Union, said there would be widespread support for the ESBOA. His own union was contemplating an even higher pay claim.
The company was positioning itself to meet competition, and "unions hold the view that management wants change to be cut out of the hide of the staff in the organisation. That is not going to happen."
He said the danger of a strike at the ESB was greater now than at any time since the last major dispute in 1991.
A spokeswoman for the company said the ESBOA claim was outside the terms of the PPF and the company could not consider a claim for a 16.5 per cent pay rise when it needed to reduce costs to compete in a deregulated energy market.
She said the ESBOA was in breach of procedures because it had not processed the claim through the company's joint industrial council, on which both management and unions were represented.
Union sources said this showed the seriousness of the situation. Workers had agreed to considerable change and 2,000 redundancies in 1996 for an average pay rise of 6 per cent, but economic conditions were different now.