The two maps here show sea surface temperatures, from ship and satellite readings, for July and January. Where the colours show yellow, green or blue against the coastline, both summer and winter, those are the lucky folk. That is where the solar electricity generation system outlined here will work best. The sun does the warming, the sea does the cooling. Boiling and then condensing liquid drives turbines. Very, very simple. No extra radioactivity needed, just that of the sun.
This is about some lucky coastal places, with no new technology,
1) Getting an inexhaustible supply of energy
2) Saving huge amounts of fresh water
3) Getting huge quantities of fertiliser from waste,
in one complex but integrated clean green system.
Ocean-cooled solar power. The Seafridge System.
Places like Cape Town, and in fact the entire west coast of southern Africa, as far up as southern Angola. Like the coast of Chile. Like California. Spain. Melbourne, Adelaide and the entire south coast of Australia. Like coastal China and New Zealand.
What do they have in common? Cold ocean water, at the surface and close to the coast. Where most places have warm sea water on surface, those regions have unusually cold water on their coastlines. A real limitless treasure, if used as below.
The west coasts of southern Africa and South America both have Antarctic Bottom Water surfacing right on their coastlines. Having grown up in a Cape Town beach suburb, I can vouch for the first, as I used to swim, dive, and occasionally poach abalone and turn blue with a numb brain, in the 10 degree C Antarctic Bottom Water that surfaces right on Camps Bay beach. Twenty miles out to sea, the water is a balmy 20 degrees C. The SE trade wind drives the warm surface water off the coast, and the bottom water from the deep south, after a very long slow journey, comes up right on the coastline. That lot is nirvana for fish and the fishing industry there, being laden with nutrients, mostly the wreckage of dead krill. which they have just found live to great depths, and not just near the surface, and so are probably our most important relatives on this planet, bar none. Next time you meet one, doff your hat.
And that lot is also nirvana for a power system that will never run out. You use it as a very efficient and convenient coolant for some fluid with a low boiling point, like ammonia, that you just used solar power to boil and that then drove a turbine making electricity.
And then you use that warmed seawater to flush your toilets, before one more trick before sending it back to the sea. You filter out the solid shit, as that is too valuable to waste, and you grow algae on it, in big ponds, if you have the space, maybe under the same space you just used to catch your solar power. And the algae then goes to the farms as fertiliser. You use the waste heat in the cooling water to warm the algae ponds, before the water goes for domestic use and then comes back laden with whiffy nutrients. The ponds take kitchen waste as extra nutrient feedstock.
The seawater is pumped to houses, via an entirely independent reticulated water system, that uses salt -corrosion-resistant poly pipes and fittings, all the way. You can now buy those off the shelf. So, no more wasting scarce fresh water where salt waster is perfectly adequate. When you've grown your algae, you pump the water, still with some dissolved nutrients, far out to sea, where the biosphere will thank you kindly for the nutrients and come back as fish for anglers and abalone for abalone poachers and similar low life.
For the power system, you pump cold seawater onto the shore. There it cools some liquid of low boiling point, like ammonia, that you just used the sun to boil and used to drive a turbine making electricity. Or, maybe you save energy by pumping the ammonia or whatever into the sea and out again, since that requires the movng of a lot less liquid. The downside is, you may lose your ammonia or other boiling liquid to the sea, in storms or from corrosion or just bad luck and that may be a serious ecological problem. If you can simply pump seawater, leaks mean nothing except maintanence and cost. And, of course, if you pump ammonia and not seawater, you don't get the salt water toilet flushing and the fertiliser.
Less fortunate places than those listed at the top of this essay have warm sea water on the surface, and cold water deep below, so you need to put huge pipes deep into the sea to get the cooling effect. India has been trying some experiments, but some of the pipes went awol in deep water, when being lowered. Storms are ever the problem, with sea-based power systems, and have for decades reduced most wave-power projects to rubble. Here, you just have a couple of securely-buried big pipelines running under the shoreline and into the sea. there is plenty of engineering experience for that.
Desert coasts with up-welling are ideal for these power systems, in that they do not lack sunlight, the real energy-source here. If the evaporating pipes are set in lines parallel to the shore, and with access bridges and tunnels for the wildlife that migrates along shorelines, and over-zealous admin types can resist the temptation to put fences everywhere, on say the Namibian coast, the jackals will be grateful. They can rest in the shade and burrow under the pipes. I saw one family using rather scarce whalebones for a shady home, near Swakopmund, once.
Cape Town has stretches of very steep coastline, that no-one can see except from boats, or access without being a serious rock climber. Those would be ideal spots for the onshore pipelines, and the turbine housings. As between the suburbs of Three Anchor Bay and First Beach, Clifton. And just north of Llundudno. If done well, the access tracks can become fine walks. That happened in the 1890's when the Pipe Track was put in above Camps Bay, a village then. Opposition from mountaineers to the new dams on top of the back of Table Mountain rapidly diminished, as the Pipe Track and the old construction cable route became very popular routes onto the mountain. Or, the whole show could go alongside the nuclear power station, which is already pumping seawater for cooling. What would probably be ideal for the evaporator is simply ordinary black rural poly pipe, maybe of 40mm diameter, laid out in the sun, on a black sand bed, perhaps. Straight of the shelf. That pipe lasts at least 20 years in the sun. I have couple of kilometres of it here, most buried but some not, and its only problems have come from the donkeys or the horses standing on it. It looks good for another 20 years.
What is here set out for coastlines, can also be applied to farm dams, if they are deep and large. Such dams show very marked temperature stratification, which can be made even stronger if you simply stir on some clay every few days. That traps the sun's heat right on the surface, so you can just about scald your hand on a hot day, in the top few centimetres. you park the poly pipe on the dam wall, where it gets maximum sunlight, run your cooling pipe.
javascript:void(0)
this dual system should be a boon for places like Adelaide (desperately short of fresh water and a bit far from the coal mines) Melbourne, Beijing, and many other cities alongside cold water. This will probably work just fine of all of Portugal and southern France.
Many cities like Vancouver have cold water along the shore - there the problem is more the solar heat. And in the end, every coastline everywhere can have these systems. Where there is warm water on top, there is always colder water deep down, and then the system as outlined in the New Scientist of with the warm water boiling the ammonia, and the deeper water cooling it at depth, can be used.
All for now.
Peter
No comments:
Post a Comment