The Electrical Trades Union NSW said this would be the first time since protected industrial action began earlier this year that it would not provide a skeleton staff during the stop work period.

This would leave Essential Energy to make alternative arrangements to address any power failures.

The ETU served notice of the protected industrial action on Wednesday afternoon. It plans 20 consecutive four-hour stoppages from 10pm Monday May 23 till Friday May 27.

ETU NSW secretary Steve Butler said workers had endorsed the industrial action in what has been an 18-month dispute with Essential Energy.

"Essential Energy management have refused to come to an agreement, have rejected a range of generous concessions from the union, have refused to allow the industrial umpire to intervene, have put forward a proposal that would see the immediate slashing of 800 regional jobs, and have launched unprecedented legal action to cut our members' pay and conditions," Mr Butler said.

"Rather than allow this dispute to continue to drag on for months or even years, union members have decided to bring it to a head with an unprecedented escalation of strike action that will see them walk out of more than 120 workplaces for a total of 80 hours later this month.

"Unfortunately, this means the stoppage may impact on electricity services for some in the community but customers can blame management and the NSW Government for their lack of will to resolve this matter."

Mr Butler said NSW Premier Mike Baird could no longer remain silent while regional jobs and services were being "slashed".

Essential Energy's Acting Chief Executive Officer, Gary Humphreys, said negotiations with unions for a replacement Enterprise Agreement started in April 2015 and included six days of conciliation in the Fair Work Commission.

"The recent notices of intent from the Electrical Trades Union to take protected industrial action over an 80 hour period appear to show a complete disregard for safety, network reliability and customers, including the many life support customers on Essential Energy's network," he said. "The unions also seem set on adding to an already challenging situation rather than helping to move the discussion towards an outcome that meets the needs of employees, customers and the business."

He said Essential Energy has remained at the negotiating table and continues to bargain in good faith, having tabled two draft enterprise agreements.

"The most recent offer from Essential Energy included maintenance of current entitlements for long service leave, as well as maintaining superannuation entitlements well above the Superannuation Guarantee Charge (SGC). However, the unions rejected this offer as "unacceptable" to its members, Mr Humphreys said.

"Unfortunately, the parties remain unable to reach an agreement and, despite union claims that an agreement is close, we remain a considerable distance apart in relation to key aspects of their respective claims, particularly with regard to proposed clauses for redundancy and dispute resolution.

"These clauses are central to negotiations as Essential Energy seeks to finalise an Enterprise Agreement that provides a greater level of efficiency and flexibility and removes unnecessary cost to customers."

Mr Humphreys said Essential Energy fails to see how further conciliation will help because negotiations have reached an impasse.