Hydrogen Please submit to this category only sites dealing with the scientific and new technology aspects of hydrogen. Hydrogen is the first element on the Periodic Table and is the smallest and lightest atom of all the elements. When it is burned with oxygen the only by-product is water vapor. This category contains links related to the research of hydrogen itself and the development of hydrogen related devices by government, scientific and private researchers. This category is for websites about the science and technology of nuclear energy.
Fusion energy is in a separate category.
Renewable Please submit commercial sites to this category only if they have substantial scientific content. Otherwise submit those to appropriate category under Business. Ocean tides are another source of renewable energy. Geothermal energy is also sometimes classified as renewable energy, but is listed separately because some geothermal sources CAN be depleted. Battery technologies are based largely on electrochemistry.