# Spatial solar panels area density through history [closed]

When working on a project, it is often useful to predict what will happen in the future, 5 or 10 years from now. Past data is needed in order to extrapolate them and make accurate predictions. How can I manage to get the area density of spatial solar panels from year 1970? This is used to calculate how much it costs to bring a square meter to orbit.

• What do you mean with area density of spatial solar panels? Do you mean cell conversion efficiency (see e.g. this NREL chart)? Please at least edit to add for what application this is for. It really isn't the same if we're talking of, say, GEO satellites or for deep space missions. Solar panels will face quite different challenges affecting their performance and reliability in different space environments (see this document for deep space mission considerations). Dec 4, 2015 at 15:37
• I mean weight per square meter ;-) Dec 4, 2015 at 15:47
• Surely you mean specific power density? Weight (mass!) per square meter is a bit of a pointless metric without also having conversion efficiency figures and then deriving power-to-mass ratio out of it. Note that cell efficiency isn't nearly the end of it, solar arrays need many other components than merely the PV cells. From actuators, radiators and structure to wiring and voltage regulators. Basically, your question suffers same nonspecificity as Lightest possible solar array?, you're only making it even broader asking for historic overview. Dec 4, 2015 at 15:54
• BTW, if you mean specific power density and you decide for which specific application or at least orbital regime, it would be possible to derive meaningful and real-world numbers for BOL and EOL from UCS Satellite Database and make a graph (with quite some work, but it's doable, it includes enough data to extract representative samples out of it for GEO - for system specific power density at least). Dec 4, 2015 at 16:12
• Bet there is a \$3000 report by Gartner with just that graph. Dec 4, 2015 at 18:35