The $150B spent on Solar PV was about 30% of investment but only around 7% of average generating capacity at 6.9GW. This global perspective shows solar as much worse investment than it is generally portrayed.
Solar suffers in two big ways relative to its best case of large utility scale installations in the desert. Only a small fraction of installed GW are in the desert. More are in less sunny climes, like Europe. Another large fraction are more expensive small scale installations on residential and commercial rooftops with lower average utilization factors. These factors will still apply as PV panels improve.
If the entire current $506B investment in generation went to StratoSolar it would provide about 140GWa, or the same generation capacity as the current investment in all types of generation. This capacity would produce lower cost electricity than the present because there are no fuel costs, and fixed O&M is a lot lower as well.
So at current prices, StratoSolar is a lower cost replacement for current generation. The certainty that PV prices will reduce with growth in cumulative capacity means that the cost of electricity will reliably reduce over time, much like semiconductors have reduced with Moore’s law.
By Edmund Kelly