Don't get your hopes up yet: This just demonstrated that the released energy (in form of heat etc) is higher than the energy input – yet the released energy hadn't been converted to electricity that could have powered the lasers.

Supposedly this would be done by a heat engine, with can normally extract 60% of energy input. So 2.5 * 0.6 = 1.5, so it is yet again not producing any surplus energy.