Wait a minute again! 'Peak' implies a rate rather than a total. (Just as 'peak speed' would be measured in 'miles/hour'. Total distance would be speed times time, which gives 'distance'.)
If they wanted to say 'power' they should use 'megawatts'. If they want to say 'energy' they should use 'megawatt hours'. It sounds as if they were talking about power since they mentioned a peak value. This means people were using energy a the highest RATE for the day. They should have said 'megawatts', the proper unit for power, not 'megawatt hours'.
Exactly; that is my point that the media was confusing demand and energy. I've noticed over the years that whenever I know something about a story being reported in the media, the reporting usually has errors in it (which doesn't lead to much confidence on my part in the media in general). The best reporting I've found is in the IEEE Spectrum (I'm talking about non-engineering articles...they had better be correct in engineering specific articles).