There's a certain ahistoric view of energy development that drives me nuts (not necessarily your comment, but it triggers my rant...)
We have switched energy resources over the years not just because it was cheaper but because it was cleaner and more sustainable. We went from burning trees (deforesting entire countries and enveloping the land in smoke and soot), using animal power (leaving billions of metric tons of shit strewn throughout our cities, towns and villages) and using animal fat (nearly wiping out all cetaceans in under a century) to burning coal (land destruction was minimized vs trees), then petroleum (getting rid of the shit and the soot), then natural gas (lowering our CO2 emissions).
At every point since technology became an important part of human existence, we've ramped up the existing technology to pull as many people as possible out of abject poverty (mainly as a side-effect of economic development, but nonetheless). Then, when we realize that that technology is unsustainable (prices shoot up), we develop the next technology and ramp that one up - using the new-found wealth to clean up the old messes and finding new side-effects that are generally more benign than the last but that become bad due to the increased scale. Rinse, lather, repeat...
This is a nerd site - we'll figure out the next step eventually and use our expanded wealth and energy to clean up the bad effects of the previous technology. Our focus should be on accelerating that process - using price pressures (like carbon taxes) to encourage research and deployment of cleaner technologies. We also need to be ready to remediate the damage we've done so we can use some of our next tranche of new wealth to restore ecologies and species as best we can.