Original sentence: According to a meta study, in which all existing studies from 1977 to.Any practical large-scale energy source must produce more energy than is used in its construction.Modern wind turbine systems have a net energy gain, in other words during their service life they produce significantly more energy than is used to build the system
Edited sentence: "Net energy gain" is an economic, rather than scientific term.According to a meta study (which is not verifiable without paying for it, and the graphs are illegible), in which all existing studies from 1977 to.Any practical large-scale energy source must produce more energy than is used in its construction, in order to be efficient, and not result in a net loss of joules of energy.Modern wind turbine systems have a net energy gain, in other words during their service life they produce significantly more energy than is used to build the system, in this author's opinion.There is no mention in the study however, that shows how many joules of energy are used to produce the turbine