Occasionally saw this on internet, do anyone think this works? "Hi. This is about an idea of generating electricity by gravitational force. Attached please the basic concept of the idea. The idea consists of two major parts. The first part of the system makes use of electrolysis of water and fuel cell. A fuel cell on the top generate electricity for electrolysis of water. And the electrolysis of water provide hydrogen and oxygen gas for the fuel cell. The energy loss from this part of the system must be minimized. And some energy from the outside is needed to initiate the system. The second part of the system makes use of the products from part one (water, hydrogen and oxygen gas) to generate electricity. Hydrogen and oxygen gas will flow upward if it is mixed with heavier gas. Water will flow downward due to gravitational force. Turbines are placed in their flowing paths and generate electricity from their motions. The system relies on gravitational force to work. If we manage to generate sufficient energy from the motions of the products to overcome the energy loss from the electrolysis of water and the fuel cell, the system can generate electricity by gravitational force."