Answer
1200 MJ
Work Step by Step
Use the definition of the efficiency of a heat engine.
$$e=\frac{W}{Q_H}=\frac{W}{W+Q_L}$$
$$Q_L=W(\frac{1}{e}-1)$$
In one second, W is the work output, 580 MJ. Calculate the heat discharged per second.
$$Q_L=(580MJ)(\frac{1}{0.32}-1) =1232.5 MJ\approx 1200MJ $$