Despite the 1,000 MW Diablo Canyon nuclear power plant unit 1 going offline June 25, as well as the permanent San Onofre Nuclear Generating Station shutdown, the requisite energy cushion remains solid this week in the face of a potential record smashing heat wave, according to the grid operator. \tIt\u2019s a big chunk\u201d of generation coming out, California Independent System Operator spokesperson Steven Greenlee said. Although temperatures are in the 100+Farenheit zone for the weekend, no conservation alerts are pending, he added. \tThe sources of power called on to fill the gap was not disclosed. \u201cWe cannot share what power plants we are dispatching as this is market sensitive information,\u201d stated Greenlee. \t\u201cI'm sure all [resource adequacy] resources are being called on to at least run at minimum load,\u201d according to Gary Ackerman, Western Power Trading Forum executive director. \tDiablo unit 1 was shut down for a \u201cweld leak\u201d according to a Nuclear Regulatory Commission report. There was an unscheduled outage after a leak in the containment building was discovered. How long the plant may be offline is unclear. \tThe price of free market electricity jumped to $60\/MWh June 26 but was back to the normal $30\/MWh by June 27 at the California Independent System Operator.