MiniLED is what the new Macbooks have. That’s an LCD panel with LED backlighting, using a backlight array with a large number of lighting zones (hundreds or thousands) to improve contrast. MiniLED also reduces blooming by limiting it to a lighting zone that is now smaller but does not completely eliminate it. Over in the of land of TVs, Samsung’s QLED and LG’s QNED displays use Mini-LED technology, and also use quantum dots to improve the color gamut
MicroLED is a directly illuminated display technology that uses millions of conventional LEDs (not OLEDs) in red, green, and blue. Each pixel has three LEDs. MicroLED displays have the potential of being the best display technology yet: as much contrast as OLED, but with more brightness and fewer problems with screen burn-in. The only commercial large MicroLED displays are things like Samsung’s The Wall and LG’s MAGNIT; they are very very expensive, with even the smallest sizes (which are still quite large) costing well over $50,000.
MiniLED doesn’t create any more heat than a standard LED backlight system does at the same brightness. Extra cooling should not be necessary unless high backlight levels are implemented; that’s going to apply to any HDR display.
MicroLED is too new to say what its eventual power consumption will be.