Sodium from ocean salt for generation of hydrogen

I remember in high school my chemistry teacher put some sodium in water and hydrogen gass was produced which went boom!! can you extract sodium from sodium chloride (ocean salt) avoiding electrolysis(energy expensive process) and with out expelling chlorine gass. All while not spending a lot of money?? If so then maybe you can then use the sodium to generate hydrogen. but I'm probably dreaming?? Anyone got some links where people have attempted this?