Originally Posted by _ben:
“The transmitter output is 500kW, that includes both sidebands and the carrier, so the transmitter efficiency (70%) is the important figure here. The fact that AM itself is only 30% efficient in that you could have transmitted the same information using only one sideband and no carrier is irrelevant to the calculation of power consumption because you didn't do that, you transmitted both sidebands and the carrier.”
“The transmitter output is 500kW, that includes both sidebands and the carrier, so the transmitter efficiency (70%) is the important figure here. The fact that AM itself is only 30% efficient in that you could have transmitted the same information using only one sideband and no carrier is irrelevant to the calculation of power consumption because you didn't do that, you transmitted both sidebands and the carrier.”
Can see your point
But the published total distribution cost for R4 was £9m in 2014, of which by deduction £4m was for AM and electric consumption was probably a large part.
The costs for 5 live AM are also about £4m.
Rather confusingly the latest financial report for 2015/16 shows the total distribution R4 cost is £6.2m, but for other radio networks with analogue is £6m. The digital only stations (4 extra, 6) are now £1.7m up from £1.5m, which might be due to inflation, more DAB sites and internet usage. So this makes national analogue FM distribution now a large £4.3m per station per year.
In the latest report the difference betwen R2 and 3 with 4 is only £200k, which must be too low for AM?. Maybe the latest report does not include R4 LW and MW? Either it assumes LW would have been switched off, or power has been reduced and the depriciation and maintence contract is minimum and the costs now put in another column?



