A fuel cell converts chemical energy of a fuel, like propane or hydrogen, into cleanly and efficiently produced electricity. Fuel cells are unique in part because of their flexibility and ability to be used in a variety of applications; they can provide power for systems as large as utility power grids and as small as a drone. There are different types of fuel cells, but today we’re going to focus on propane fuel cells.
Why Propane Fuel Cells?
When people think of fuel cells, hydrogen is often the first type to come to mind. They’re reliable in normal conditions and have low greenhouse gas emissions.
However, hydrogen presents a host of limitations: high cost, lack of portability, patchwork delivery infrastructure and unreliable performance in extreme weather conditions. However, it is inefficient to convert hydrogen into power when compared to how efficiently the same process is done with propane.
Just like hydrogen, propane-powered fuel cells burn clean with low-carbon emissions. But propane fuel cells have the added benefits of reliability in extreme temperatures and no routine maintenance requirements.
As a fuel, propane has a host of benefits. It’s cheap, reliable and readily available — even at offgrid or remote locations anywhere in the world. Plus propane does not degrade over time. While diesel can hydrolyze, oxidize or grow microorganisms within six months of storage, propane can remain stable for 10 to 30 years. It’s also great in extreme weather conditions, including freezing temperatures thanks to the lack of liquid water. That’s why our Solid Oxide Fuel Cell (SOFC) systems can sit idle for years and then cycle on when needed. Especially in remote areas where fuel must be airlifted, the reliability of propane is crucial.
How Propane Fuel Cells Work
Propane fuel cells electrochemically convert propane into electrical power. A fuel cell is composed of an anode, cathode and an electrolyte membrane. An anode is the negative electrode that propane atoms enter into, releasing their electrons and oxidizing during the electrochemical reaction. The cathode is the positive electrode where the positively-charged propane atoms take on electrons from the external circuit and are reduced during the electrochemical reaction. Here’s a quick step by step of the process:
- Propane breaks down into hydrogen and carbon monoxide (both fuels for SOFCs).
- Hydrogen enters the anode and electrons are ripped away, traveling to the cathode where they combine with oxygen to make an oxygen ion.
- The oxygen ion travels through the electrolyte and combines with the electron-deficient hydrogen to form water.
- Power is then harnessed by placing a load, battery, pump, light bulb, etc. in the circuit between the anode and the cathode so that the removed electron has to pass through the load device to make its way back to the cathode.
- The presence of water and carbon monoxide in an SOFC will react to form carbon dioxide and more hydrogen — this reaction is called the water gas shift reaction.
And propane fuel cells can be used in a wide range of applications thanks to how quiet, clean, and dependable they are. You can see how Adaptive Energy’s customers are utilizing fuel cells for backup and off grid power here.