Renewable energy can supplement existing fossil fuels but frankly are and always will be a drop in the ocean.
I developed a renewable fuel to replace heavy fuel oil in power stations back in 2004 and currently ship abt 30,000mt p.a to one UK power station by ocean tanker. I could perhaps increase this to 100,000mt but that would run a 2000mw power station for abt a month.
We have to change our thinking and forget about burning anything to create power. Wind power is a total and utter waste of time and money. Nuclear power is ok until cold fusion is perfected. Solar power will rely on rare earths and metals from China who will very soon not play anymore - goodbye photovoltic cells, cell phones, lcd tvs etc etc.
Wave power is about as reliable as wind power. The only reliable souce from the sea is Tidal power or hydrogen extraction. Oil from Algae is fraught with environmental dangers.
We have to learn to make the most of what we have until science provides an answer to our energy problem.