If it’s in low earth orbit as described, it would mostly be intercepting sunlight that would hit the earth’s surface anyway (although she also says it could collect light 24 hours a day, which would imply a much higher orbit).
But solar panels only convert a fraction of the incident light into usable power—most of it is re-radiated as waste heat. In that respect an orbital array would heat the earth less than a surface array, whose waste heat is trapped by the atmosphere. (And either one would heat the earth less than burning fossil fuels.)
If it’s in low earth orbit as described, it would mostly be intercepting sunlight that would hit the earth’s surface anyway (although she also says it could collect light 24 hours a day, which would imply a much higher orbit).
But solar panels only convert a fraction of the incident light into usable power—most of it is re-radiated as waste heat. In that respect an orbital array would heat the earth less than a surface array, whose waste heat is trapped by the atmosphere. (And either one would heat the earth less than burning fossil fuels.)