Yes, there is roughly a 25% increase average over

Yes, there is roughly a 25% increase average over the years, but 12 Gw/year solar installed in the US and 30-50 Gw installed in China is pitiful. The IEA says 303 Gw have been installed worldwide by the end of 2016- total. The need for solar to do its share to mitigate global warming is measured in Terrawatts (Tw). One Thousand Gigawatts = 1Tw.

Mercator issued a paper last week that thought earlier projections by other energy agencies studying the problem had underestimated our potential to install (their target of) 25 terrawatts of solar. They think it can be done between the range of 2025 to about 2040. 2025 is only about 8 years from now. That's about 3000Gw installed per year. 2040 is about 22 years away and thats only about 1000Gw per year for 22 years plus some.

Large solar plants today are about 500Mw/year production, or half a Gw.

Solar cell efficiency determines how many solar cells are needed to make
1 Gw of installed cells, The higher the efficiency, the fewer solar 'panel' would be needed.

The second factor that determines how much 'Gw/year' can be produced at a factory is the speed of production. The faster the production, the more Gw/yr can be produced, of both low and high efficiency solar cells. Faster is better.

Solterra will make solar cells by Roll-to-Roll (R2R) printing presses, much like those in major daily newspaper companies. Starting speed is 100meters/minute. Faster speeds are possible.

If Solterra can match current Silicon panel efficiencies, but by using mass production increase the speed of making them, it would be possible to make multiple Gw/yr at each factory, and the price should fall somewhat proportionally.

If and when Solterra ramps up and goes into production, I think it possible to have multiple gigawatt/year factories. Its possible the combination of faster and faster printing speeds combined with incremently increasing the quantum dot efficiency will result in far less solar cell units needed to reach a Gw/year.

China said in its 2016-2020 five-year plan in March that it would aim to keep total energy consumption below 5 billion tonnes of standard coal equivalent by the end of the decade.

It aims to cap coal-fired power capacity at 1,100 gigawatts by the end of 2020, an estimated 55 percent of the country’s total. Coal-fired capacity stood at 960 GW at the end of last year, accounting for about 64 percent of the total.
https://www.reuters.com/article/us-china-ener...SKBN14G1V4

Note: extrapolating 1100Gw is 55% of 2000Gw (or 2 Terrawatts) China's total energy consumption/year.

I don't know when QMC will start up Solterra and ramp it up after proper testing. My point is that the cost of the factories is not expensive, and depending on how fast both the R2R machines and construction goes,
China could absorb 200 factories and perhaps India and the middle east could absorb 150Gw of production per year each.
500 QD solar cell factories producing 1 Gw/yr would equal .5 Tw/year.
500 QD solar cell factories producing 5 Gw/yr would equal 2.5 Tw/year.
That would be 25Tw in 10 years, within the range of Mercators hoped projection, and as the US and other countries open their own Solterra plants, the projection gets shorter and shorter.

My point is not whether the numbers are right, because it is hypothetical.
My point is that we as a planet have to start thinking with the end in mind -
the desired result, and figure out what we have to do to get there.