One of the largest U.S. dairy operators implemented an energy management and cost-reduction system using natural gas.
Fuel cells might sound futuristic, but they were invented in 1932 and put to commercial use by NASA in the 1950s. They are now most common as a power source for buildings and remote areas but continual improvements in technology are quickly bringing them into wider use.
A fuel cell is a device that uses electrochemical reactions to generate electricity. The only byproducts of this process are water and heat, which means that fuel cells are a low-emissions source of power.
There are various types of fuel cells, but they all have a similar structure consisting of an electrolyte and two catalyst-coated electrodes. Regardless of which fuel is used—often hydrogen—the process starts with a catalyst splitting negatively-charged electrons from positively-charged protons. An electrolyte membrane allows the protons to travel through to the positively-charged cathode but repels the electrons, which must go around via an external circuit, the movement of which forms an electrical current.
Fuel cells are remarkably versatile: they can power things ranging in size from factories to laptops. And their cost has plummeted by as much as 95 percent in the last several years, making them an option for powering consumer products.
Fuel cells can be used as stationary power supply for large entities like buildings and even cities, or as portable power for small devices like handheld electronics. They can also power vehicles, and automakers are now producing cars powered by fuel cells. Hyundai released the 2015 Tucson Fuel Cell SUV and Toyota is bringing a compact hydrogen car, the Mirai, to the U.S.
Hydrogen, the fuel most commonly used in these cells, is often created from natural gas, which is the cleanest burning fossil fuel. However, while fuel cells create true zero-emissions energy, the process of hydrogen-production does produce some greenhouse gas emissions.
However, it is possible to use electricity to split water into H2 and O, a process that can be powered by solar or wind energy. Other possibilities for creating hydrogen include biomass, biogas and possibly algae. Using renewables to create the hydrogen that feeds fuel cells can create a cradle-to-grave low-emission energy source.
Barriers to wider use of fuel cells include issues with cost, durability, size, weight and heat and water management. But research and development is advancing rapidly and there is no doubt that fuel cells will become an increasingly large part of our energy-production mix.