http://spectrum.ieee.org/energy/renewables/moores-curse
In 1965, the year in which the number of components on a microchip had doubled, Gordon Moore predicted that “certainly over the short term this rate can be expected to continue.” In 1975 he revised the doubling rate to two years; later, it settled down at about 18 months, or an exponential growth rate of 46 percent a year. This is Moore’s Law.
As components have gotten smaller, denser, faster, and cheaper, they have increased the power and cut the costs of many products and services, notably computers and digital cameras but also light-emitting diodes and photovoltaic cells. The result has been a revolution in electronics, lighting, and photovoltaics.
But the doubling time for transistor density is no guide to technical progress generally. Modern life depends on many processes that improve rather slowly, not least the production of food and energy and the transportation of people and goods. There is no shortage of historical data to illustrate this reality, and I have calculated representative rates for the decades coinciding with the development of transistors (the first commercial application was in hearing aids in 1952) and microprocessors, as well as the rates for the entire 20th century, or even longer.
Corn, America’s leading crop, has seen its average yields rising by 2 percent a year since 1950. The efficiency with which steam turbogenerators convert thermal power to electricity generation rose annually by about 1.5 percent during the 20th century; if you instead compare the steam turbogenerators of 1900 with the combined-cycle power plants of 2000 (which mate gas turbines to steam boilers), that annual rate increases to 1.8 percent. Advances in lighting have been more impressive than in any other sector of electricity conversion, but between 1881 and 2014 light efficacy (lumens per watt) rose by just 2.6 percent a year, for indoor lights, and by 3.1 percent for outdoor lighting (topped by the best low-pressure sodium lamps).