Historically, new energy sources and technologies have taken 50 to 100 years to become significant contributors, as oil did in increasingly replacing wood, whale oil and coal more than 100 years ago.
(new energy sources and technologies; have taken; 50 to 100 years; to become significant contributors) (new energy sources and technologies; to become; significant contributors) (oil; did; T:in increasingly replacing wood, whale oil and coal more than 100 years ago)
new energy sources and technologies new energy sources and technologies oil
have taken to become did
50 to 100 years to become significant contributors
significant contributors
T:in increasingly replacing wood, whale oil and coal more than 100 years ago