In terms of energy production - solar, wind, hydroelectric (dams), geothermal (heat from the earth), waste to energy (burning trash for fuel or capturing gas from landfills). I have even heard of turbines placed in the ocean that use the motion of the waves to create energy. Obviously, getting the energy to where people can use it is a challenge.
Is that what you're asking? Or are you asking for green technologies like electric cars, LED lighting, rechargeable batteries, new kinds of insulation for homes, and other things like that?