[David]

I expect gas turbines will be the main power generation machines for the next 30 years as renewables slowly take over and steam plants (coal and natural gas) age out of competitiveness. If you look at power generation sources over the last 20 years, natural gas powered plants have steadily grown while coal has nose dived. The vast majority of new gas plants are gas turbines (simple, combined cycle, and co-gen) since almost nobody is building new steam generator gas plants. Renewables have been growing at exponential rates for several years but even at that rate it will likely take 20 years to become the majority source.