It all starts with a question: Global tidal energy harvest?

Future tidal energy production hotspots, based on the energy dissapated as water collides into continental shelves.

Tidal energy - and how to harvest it - came up twice in the past week.  Once via an engineer's presentation to the Washington Coast Marine Advisory Council, and later in conversation with a rural coastal community leader.  The former was interested in generalized sustainable energy production for the region, while the latter was in regard to addressing energy needs for desalinizing water for local use.

Today's energy infrastructure has a definitive footprint on the economies and environment of today's energy-producing regions.  Oil refineries, windmills, and mines create familiar yet profound landscapes.   Tidal energy has yet to take hold, but has massive potential: potential for human development demands to further alter our oceans, and potential for the cosmotic planet-moon-gravity-water* relationship to feed these demands in perpetuity**.

How would new mega-infrastructure for tidal energy capture play out locally? How would it impact global systems?  The map above points out tidal energy hotspots around the globe, where a new industry could take root.  Below is a map of current oil and shale hotspots. 

For comparison: oil and shale gas basins, drivers of today's world.  Map via US Energy Information Administration.

*Earth's gravity holds the water to the planet, while our moon's gravity pulls it away.  As the two rotate and revolve, we get tides.  

**though the slowing of Earth's rotation could alter these dynamics... or cause an increase in earthquakes, and resulting events such as tsunamis. Though this all may likely occur on a timescale greater than we can usually act on, many coastal communities have already experienced, rebuilt from, planned for tsunamis.  Much of this planning is happening today, so perhaps this line of thought could factor in to risk assessment, project design, and prioritization: 
the creeping speed of Earth's deceleration, 
connected to potential increased likelihood of earthquakes in certain locations, 
connected to the likelihood of ensuing tsunamis impacting these locations... 
Risk = impact x probability. 

Egbert, G.D.; Ray, R. (2001). "Estimates of M₂ tidal dissipation from TOPEX/Poseidon altimeter data". Journal of Geophysical Research. 106 (C10): 22475–22502., via Wikipedia "Tidal Resonance" page