Electricity utility Eskom was staring down the barrel yesterday amid a leadership struggle, a construction workers' strike at its flagship power station and another round of power cuts as the government revealed that load-shedding was costing the economy tens of billions of rands a month. Yesterday, construction at the multibillion rand Medupi power station was brought to a halt by a strike.As if that were not enough, Public Enterprises Minister Lynne Brown admitted that she was deeply concerned about the way the parastatal was being run as word spread that Eskom's board was meeting to oust embattled chairman Zola Tsotsi.The strike at Medupi, involving 21000 workers, was called to protest against the employment of foreign workers, non-payment of completion bonuses and forced evictions from housing.The National Union of Metalworkers of SA's Steve Nhlapo said: "Black artisans and general workers are being unfairly targeted. While their white counterparts stay in decent accommodation, blacks are being forced to live in hostels. Eskom blames the subcontractors, who blame Eskom."Eskom spokesman Khulu Phasiwe said strikes over the past three years had set the construction project back by a year.He said Eskom was not aware of the workers' grievances.In parliament , Brown told the public enterprises portfolio committee that load-shedding was costing the economy between R20-billion and R80.1-billion a month.She said she had asked for legal advice on how she could intervene in the running of Eskom.Brown said that, as a representative of the Eskom shareholder, the government, she was responsible for the company but was not allowed to participate politically, operationally or managerially in its running.Eskom's board was reported to be meeting yesterday to remove chairman Zola Tsotsi. But Eskom's media liaison department and Deputy President Cyril Ramaphosa denied that such a meeting was taking place.Brown said she would take a decision on Tsotsi once she had received a resolution from the board.The National Union of Mineworkers accused Tsotsi of interfering with the awarding of tenders.Suspended Eskom CEO Tshediso Matona has taken up the matter of his suspension with the Commission for Conciliation, Mediation and Arbitration ."In accordance with CCMA practice and procedure, the matter will be set down for conciliation and all parties will be notified," the commission said.Matona and three other Eskom executives were asked to step down earlier this month while the parastatal conducted an inquiry into the "challenges" it was facing.As Eskom announced yet another round of stage 2 load- shedding yesterday, Ramaphosa assured the country that Eskom was working "day and night" to resolve the energy crisis.Responding to questions in the National Council of Provinces while carefully avoiding the use of the word "crisis", Ramaphosa said South Africa had "overcome worse problems than this" and "cool heads and strong will" were needed to solve the power crisis .He said he would convene a summit - which would include representatives of labour, business and Eskom - to discuss "the issues which face us with regard to electricity provision".Energy analyst Ted Blom said: "Until spare capacity is generated, vital maintenance, especially preventative maintenance, cannot begin."..