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By Rajiv Sekhri
TORONTO, Aug 18 (Reuters) - The auto industry in Ontario scaled back production on Monday after the provincial government urged energy conservation in an attempt to return the power system to normal after the worst blackout in North American history.
Steel companies also cut back to help Canada's largest province save electricity and the government asked nonessential workers to stay home.
Even Burger King delayed until Thursday the Ontario leg of a countrywide promotion offering its Whopper sandwich for C$1 "out of respect" for the province's call to curb energy use.
General Motors of Canada said about 11,500 of its workers across Ontario were either laid off temporarily or were working shifts during non-peak hours to help save power.
Seven of General Motors' nine facilities in Ontario had cut back operations, spokesman Stew Low said. He said he could not break down how many workers were laid off and how many were working different shifts.
Ford Motor Co. of Canada said it had cut the day production shift at its Oakville, Ontario, plant and closed its headquarters for the day to save power.
About a 1,000 workers build Ford cars during the day shift at Oakville and 600 people work at headquarters, Ford Canada spokeswoman Lauren More told Reuters.
DaimlerChrysler Canada said it was eliminating nonessential lighting and electrical use at all of its facilities across Ontario.
Its assembly plant in Windsor, Ontario, was shut on Monday and its casting plant in Toronto was operating at 50 percent capacity. The company said it had idled two laboratories.
DaimlerChrysler said the Windsor assembly plant would operate the midnight shift but the day and afternoon shifts on Tuesday would be canceled. Its trim plant in Ajax, Ontario, would not operate for the week.
One of Honda Motor's plants in Alliston, Ontario, cut down the length of its shifts to help conserve energy. The morning shift ended after 1.5 hours and the night shift on Monday will be cut to six hours. But company spokesman Ron Lietzke in Ohio said a second plant in Alliston was running on a normal schedule.
GM and Ford said they did not know if they would step up production on Tuesday. "At this point we are taking it on a day-by-day basis," Ford's More said.
Toyota Motor Canada said it was shutting down both shifts assembling its Lexus model at its Cambridge, Ontario, plant in addition to cutting back on lights and air conditioning.
The electricity supply in Ontario was still not at full steam on Monday as several nuclear generators that went out of service during Thursday's blackout were not yet back on line. More than a third of the province's electricity comes from nuclear stations.
Algoma Steel said it was "working with the province to conserve power usage and shift demand to off peak hours" but did not offer details. Steelmaker Dofasco Inc. also said it was curbing power use but offered no details.
Offices, banks and businesses in downtown Toronto lowered lights and shut off electric billboards. Elevators were slowed, escalators stopped and cut air-conditioning cut back.
"We've had major cooperation from the major sectors," said Ontario Premier Ernie Eves, who on Sunday urged energy users, especially big firms, to cut electricity use in half as the work week started.
($1=$1.39 Canadian)