As production volumes increase, costs fall. For example, a product with an eighty percent learning curve will experience a twenty percent price drop when the volume is doubled. If production is doubled again, the price will decline an additional twenty percent. This is common sense. When volumes swell and you are manufacturing tens of thousands of cars per year, the marginal cost of making one more car will be very low.
Solar cells are currently at the cottage industry scale.
A single nuclear power plant produces twenty-five times as much electricity in a year as will all the solar cells sold in the entire world last year. The solar industry should learn from the experience of the electronics industry. Consider, for example, the history of the integrated circuit. In 1961, Texas Instruments began producing integrated circuits for small, specialized applications. The earliest versions were very expensive.