Solving the energy crisis, polution, and global warming

Simple solution to clean up fossil fired electric plants, make us independent of oil, clean up ground water of nitrates and phosphates, and fix global warming.

Take all the fumes from the chimney of the coal/gas fired plant and bubble it through large tanks filled with algae, and then continuously refine diesel oil from the algae.  Use coal fired plants to warm and feed the algae C02.  The CO2 is captured by the algae and then used in our cars.  Large algae tanks on top of every building in every city would scrub more C02 from the air.

The great thing about the algae is that it would be easy to filter from water, you just need a strainer, so it would be simple to concentrate and ship to small refineries to extract the oil. And then you can run all the new cars we sell in the US off the bio-diesel.  http://science.howstuffworks.com/environmental/green-science/algae-biodiesel.htm  You could even run an electric plant on biodesiel that is produced in a few square miles of tanks surrounding a plant.  Much of the energy from the sun falling on square miles of algae could be captured.

It is claimed that current methods of trying to use algae as bio-fuel is not maintainable.  http://news.sciencemag.org/scienceinsider/2012/10/large-scale-algae-biofuels-curre.html but that is because they are trying to treat a tank of algae like a field of beans.
 
The complaint of using too much water is nonsense, because you can just use salt water from the ocean for algae production. Algae grows great in brackish or otherwise dirty water.  The treated output from sewage treatment plants could make a great input to the algae tanks, otherwise useless water that is polluting lakes and rivers.  One of the issues with this waste water is that it creates algae blooms that kill the rest of the life in a river.

Sewage can be use used as fertilizer for the algae with just a little processing.  Ironically, phosphates and nitrates are a huge problem for the environment from sewage treatment plants. I don't see excesses of anything as a problem.  I see an output looking to be utilized as an input to another process.   Any nitrates not provided by the treated sewage could  be provided by using alternative methods to get the needed nitrogen from the atmosphere, such as using the same bacteria that clover uses to create nitrates. http://www.biology.ed.ac.uk/archive/jdeacon/microbes/nitrogen.htm   If we are using single celled organisms for fuel production, why not use bacteria for nitrogen fixing as well?

The heat and massive amounts of CO2 bubbling through the algae tanks would maintain massive growth.  Air can be bubbled through the tanks to rapidly extract excess CO2 from the atmosphere. The treated waste water from the sewage treatment plant would feed the algae, preventing our rivers, lakes and ground water from becoming poluted.  Bacteria can be used to provide the rest of the needed nutrients as they do in the rest of Earth's biome.