At this stage, it's groundbreaking what's going on with artificial black holes. As it's been said, it's good to confront the universe itself - we could start with a white hole lab simulation. Remembering how neutron star creates gravitational waves entering black hole we should look for something bigger to smash black hole, some stuff accessible in the laboratory. Afterward, to accumulate that burst of energy proper setup should be designed. It's vital to know the universe whether black-to-white hole conversion is an energy gainer or drag, or even doable beside 'strained', 'overflown', and 'stretched' formulas on some piece of paper. White holes are yet to be discovered in the observable universe.
If you want reality, confront the Universe itself.