The article contains the phrase "300 megawatts (MW) of electricity, which is enough energy to power 300,000 homes for one year." Why "one year", not "one second

The article contains the phrase "300 megawatts (MW) of electricity, which is enough energy to power 300,000 homes for one year." Why "one year", not "one second" or any other time interval? A generous interpretation might be that the "year" is a statement about an average taken over seasons, during which power consumption might vary. But I fear that the article instead betrays simple ignorance, as is the case in many non-technical discussions of power. I wonder what is it about power that seems so difficult for soft-science writers to comprehend. After all, their readers are paying power bills that are expressed in kilowatt-hours.