The currents in the open ocean have huge potential energy for renewable energy production.
Many designs to date have focused on placing turbines in the flow of water, yet these
turbines are likely to mean high maintenance costs and collisions with marine life.
My proposal is to capture the energy in the ocean with a low maintenance system that
leaves all the complicated generators and other stuff on board a electricity / hydrogen generating ship.
The only thing in the water a large drogue chutes that can come in a number of designs.
In the sketch on the left the
drogue chute can be let out many miles from the 'The Energy Ship.'
generating power all the way.
The Energy Ship needs to be securely anchored in an area of ocean current, the drogue chute is then
let out and the momentum of the water turns the electricity generators. The electricity is used via electrolysis to
create hydrogen. Hydrogen is then shipped to shore  for use as fuel in
power stations, cars or domestic heating systems etc.
Some very basic concepts for a airborne drogue chute has been patented (web link) in the
USA, several years ago but seem to come to nothing. See IP rights for more.
Today with high tensile wires and the brute force of the ocean currents; ocean current energy can be harnessed that is not an eye sore to the public, does not need undersea cables, can be moved at short notice and hence this type of energy production is unlikely to have public opposition.
Fishing vessels are the only significant hazard; that said the risk of entanglement with
fishing nets is probably greater for the underwater turbines than drougue chutes.
Hence in open ocean, radar and GPS positioning would provide enough
safety infomation to avoid problems.
Furthermore the drogue chute would benifit from a surface marker buoy for added safety.
The drogue chute concept can come in a variety of designs (see power point file) but in all cases the chutes travel with the flow of water away from the Energy Ship. The designs can be improved upon through water tank testing.
See also my page called Why is the world not using OTEC ???