Cladophora algae is a pest unless you want to make a better battery. Typically gunking up the Baltic Sea this organisms nanostructure has been found to increase charge density significantly for cellulose-polymer batteries. At 25 and 33 mAh /gm this technology appears to be within striking distance of NiCD and NiMH. Unfortunately it appears to still be a laboratory curiosity. It will take a while before we see this technology available.