In spite of the title, the article explains that the cell uses solar light, obviously.<p>> <i>Those metabolic processes generated an electrical current -- 8 microamps per square centimeter of cell -- for 13 straight days.</i><p>That is 80 milliamps per square meter. I cant find the voltage. My guess is 1V or 2V, but let's be optimistic and assume 10V. That is 800milliWats per square meter = 0.8 W/m^2, i.e less than 1W/m^2.<p>For comparison a solar panel has approximately 100-200W/m^2<p>(If you prefer Imperial units, 0.1 per square feet vs 10-20W per square feet.)