An electric machine is presented. The electric machine includes a hollow rotor; and a stator disposed within the hollow rotor, the stator defining a flow channel. The hollow rotor includes a first end portion defining a fluid inlet, a second end portion defining a fluid outlet; the fluid inlet, the fluid outlet, and the flow channel of the stator being configured to allow passage of a fluid from the fluid inlet to the fluid outlet via the flow channel; and wherein the hollow rotor is characterized by a largest cross-sectional area of hollow rotor, and wherein the flow channel is characterized by a smallest cross-sectional area of the flow channel, wherein the smallest cross-sectional area of the flow channel is at least about 25% of the largest cross-sectional area of the hollow rotor. An electric fluid pump and a power generation system are also presented.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH & DEVELOPMENT
 One or more aspects of the invention described herein were developed under Cooperative Agreement DE-EE0002752 for the U.S. Department of Energy entitled "High-Temperature-High-Volume Lifting for Enhanced Geothermal Systems." As such, the government has certain rights in this invention.