It's 50 MW per borehole, a power station typically generates power from a largish number of holes. A big geothermal plant on Iceland can have 30 boreholes, which with the new method could then produce 1.5 TW, 54 % of total capacity. Of course, how much is actually possible to take out at given size depends on the size of the magma system you are tapping and how fast it refills.