This one shows total irradiance for the state of Iowa, which is sort of close to the center of the country:

http://www.energy.iastate.edu/solarcalculator/solarmap.htm

I predicted 249 total (125 visible) watts per square meter. During the summer for Iowa, ie the growth season, they show just about exactly the same thing. So maybe I should not make any changes to my data... I think it is fair to ignore the absorption bands for ozone, CO2, etc., as long as the total radiation is roughly correct, as well as the general shape of the spectrum.

Obviously it is not cast in stone. Here are some other things that can affect the design of a space greenhouse:

- the absorption spectrum of plants for photosynthesis can vary significantly in terms of what colors are preferred. This is because there are several pigments that contribute to photosynthesis and these are present in different amounts depending on the plant species.

- different species of plants also prefer different total radiation, for example house plants require about one-quarter of the light that fruit trees require. Most common food crops are somewhere in between.

I did the best I could with the information available to me, and I think I did a good job. :)

By the way HAPPY NEW YEAR !
Best wishes.