Yeah that article is for lack of a better word.... rubbish.....
I save over > 75% of my pools original energy cost by just running the pumps at night on cheaper tariff power.
My arduino based pool controller only runs the pumps/salt cell during expensive power hours IF its swimming season and the sun is providing enough heat to gather from the roof solar water collectors.... In Summer ( swimming season ) the pool runs for 8hrs to filter/chlorinate , so if there is only 2hrs of sun that day, the pumps will wait until cheap power times and run the remainder then. In Winter, only 4hrs is req so it just runs at night..
Its saved me thousands... ive not yet needed to replace the pump, but when I do, it will be a VS pump.