The cost of energy is increasing so the higher the efficiency the lower the cost of transmission. There is no official DRM study but a lot of practical data. According to reputable transmitter manufacturers, in DRM AM the savings are between 40-80% of analogue power and in DRM FM up to 90%. The new multi-bloc use of one transmitter and one antenna for up to 18 audio services and 6 data services, makes DRM a truly energy saver of the highest order. In order to find out what the savings for your particular transmitter and case would be, we have created a publicly available tool you can use. See energyefficiency.drm.org for information on how to get access and a video that shows how easy it is to use to get real data.