Total AM radio stations authorized to operate at night in the US: 4172
Class A stations: 74
Class B stations: 1770
Class C Stations: 1062
Class D Stations: 1265
Total power consumed by AM radio stations operating from midnight to 6 am: 119367.9 kWh/Day 43569291.7 kWh/year
Station class Total RF power (Kilowatts) Ave RF station power (Kilowatts) Efficiency (%) Total AC Power (Kilowatts) kWh/Day (all stations) kWh/Year (all stations) Cost per day (all stations) Cost per year (all stations)
A 3155 42.63 0.57 5535.1 33210.5 12121842.1 $3,653.16 $1,333,402.63
B 6560 3.73 0.536 12238.8 73432.8 26802985.1 $8,077.61 $2,948,328.36
C 1020 0.96 0.536 1903.0 11417.9 4167537.31 $1,255.97 $458,429.10
D 87.11 0.069 0.4 217.8 1306.7 476927.25 $143.73 $52,462.00
Totals 10822.11 19894.7 119367.9 43569291.7 $13,130.47 $4,792,622.09
Total cost per year based on electric rate of: 0.11 per kWh
Total CO2 emissions based on: 1.7 pounds of CO2 per kWh 74067796.0 Pounds/year
Total SO2 emissions based on: 0.00412 pounds of SO2 per kWh 179505.5 Pounds/year
Total Nox emissions based on: 0.00348 pounds of Nox per kWh 151621.1 Pounds/year
Notes:
Power consumed is based on the transmitter power output multiplied by the average AM solid state transmitter efficiency,
It does not include such things as air conditioning or suplimental cooling loads, or other loads which may not be present
if the transmitter is turned off.
Radio station data from the FCC data base as of April 23, 2009 and includes all stations authorized to transmitt at night time.  It does not include
Construction permits, applications, planned us or critical hours use.
Transmitter efficiency data is an average obtained from US solid state transmitter manufactures, Harris corporation, Nautel and Broadcast
Electronics.  Among those manufactures, the average Power Line to RF efficiency is 53.6%
Electrical power rate data is from the US department of energy and is an agrigate for all US locations, individual rates may vary
Emissions data is from the US environmental protection agency