Narrative:

I was conducting multiple practice instrument approaches in actual IMC in an aircraft with newly-installed modern glass panel avionics; after having conducted two previous VFR flights on previous days with practice instrument procedures in VMC.while executing the published missed approach procedure for the GPS xy approach; after entering IMC my engine monitor began flashing an alarm for low bus voltage less than 24 vdc. Indeed the alternator had stopped charging leading to the battery supplying all the instrumentation with power. Resetting the alternator failed to bring it back on line.I knew I had only 20 to 30 minutes maximum of power available from the ship's battery. I requested the GPS xy back into ZZZ for a full-stop landing. While executing the approach I turned off the few items I felt I could do without; including the #2 nav/com and all lights.the controller vectored me to the final approach course and I broke out on the GPS xy and landed without further incident.the following day I flew the aircraft under VFR conditions to a repair facility where the alternator; which had failed; was replaced.

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Original NASA ASRS Text

Title: The pilot of a C210 reported the loss of the alternator during climb on a missed approach in instrument conditions. A successful landing at the airport was completed.

Narrative: I was conducting multiple practice instrument approaches in actual IMC in an aircraft with newly-installed modern glass panel avionics; after having conducted two previous VFR flights on previous days with practice instrument procedures in VMC.While executing the published missed approach procedure for the GPS XY approach; after entering IMC my engine monitor began flashing an alarm for low bus voltage less than 24 VDC. Indeed the alternator had stopped charging leading to the battery supplying all the instrumentation with power. Resetting the alternator failed to bring it back on line.I knew I had only 20 to 30 minutes maximum of power available from the ship's battery. I requested the GPS XY back into ZZZ for a full-stop landing. While executing the approach I turned off the few items I felt I could do without; including the #2 nav/com and all lights.The controller vectored me to the final approach course and I broke out on the GPS XY and landed without further incident.The following day I flew the aircraft under VFR conditions to a repair facility where the alternator; which had failed; was replaced.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.