Surf wrote:Tanada wrote:Possible method 5 only slightly tested. Take SPAR type structures far out to sea and fit them with large wind turbines. Use those turbines to power pumping equipment pulling cold deep mineral rich water up from below 1000 feet/300 Meters down and spraying it out onto the surface waters. The mineral rich deep water behaves exactly like the Method 4 fertilizer above and in some ways is much simpler to accomplish. This is mimicking nature, anywhere in the deep ocean where a sea rise like a reef or island exists the ocean currents are forced upward and deep waters are brought to the surface creating some of the best fishing grounds on Earth. The Flemish Cap and Grand Banks of the Atlantic coastline are examples of this, as is the Dogger Bank in European waters.
You don't need much to pump water. A buoy with a couple of solar panels can supply enough power to run small air and water pumps. A small 10 GPM pump can pump 7000 gallons in one day assuming 12 hours of sunlight and the air pump can aerate all that water to insure it is has adequate CO2 levels. From what I have read it doesn't take a lot of fertilizer to to trigger an algae bloom.
If you string rope between the buoys you can attach and grow seaweed on the rope. Then periodically a small ship would come out and strip off some of the seaweed. On shore the seaweed can be fermented into ethanol that can be used as fuel and the waste water from the fermentation tanks can be used to fertilize farm fields. If you look at EROEI studies of Ethanol production most of the energy used to make ethanol is used to heat and pump water. Solar and wind power with flow battery backup can easily provide the needed power to run the plant.If you consider the size of the ocean and assume all cars in the future get 40 to 50 miles per gallon it might be possible to replace fossil fuel use with Ethanol from seaweed. If some of the Ethanol is placed into long term underground storage it can even be CO2 negative.
Excess fertilizer use on farm fields is currently causing large algae blooms near river deltas causing "dead zones" ere no fish can live. Growing seaweed in these areas could eliminate the dead zones, recycle the fertilizer and provide use with large quantities of ethanol. It would eliminate several problems at once with very little excess cost added to the economy.
If you want to do it on a small unit scale then an air compressor, possibly a directly coupled wind turbine or a solar electric system works just fine, you still need the thousand foot pipe for the water. The simple way to draw up the water and aerate it is to inject compressed air into the water draw pipe about 100 feet/ 30 meters down. The air bubbles rise and expand inside the pipe and both aerate and push the water up towards the surface. The fizzing mass arrives at the surface well mixed and aerated, and inertia moves it out of the way so that more water can rise up through the pipe as it exits.