Hyzon Glossy of Terms
HYDROGEN
BLUE HYDROGEN: Hydrogen produced from natural gas through combustion (steam methane or auto-thermal reforming); the resulting carbon emissions are captured and stored instead of being released into the atmosphere.
CARBON INTENSITY: The amount of carbon that is produced by a process (e.g. generating electricity. The lower the carbon intensity, the more environmentally friendly the process).
GRAY HYDROGEN: Hydrogen produced from natural gas through combustion (steam methane or auto-thermal reforming), resulting in carbon emissions from the reforming process.
GREEN HYDROGEN: Hydrogen produced from renewable resources with no carbon creation (e.g. electrolysis powered by renewable sources like wind, water, or solar).
HYDROGEN HUB: Facility at which hydrogen is produced. Requires feedstock and production technology.
HYDROGEN INFRASTRUCTURE: Access to hydrogen, including the molecule itself, and required distribution and dispensing support (stations, pumps, etc.)
TRUCKING
BACK-TO-BASE: A vehicle that begins and ends a shift at the same location (e.g. garbage trucks, drayage, construction, transit vehicles).
CHASSIS: The load-bearing base frame of a vehicle.
HIGH UTILIZATION: An asset – in this case, a vehicle or production/refilling station – that functions for much of its lifetime. Highly utilized assets are more cost-efficient, as each asset produces more work and revenue over its lifetime. Specifically:
Vehicle: a heavy-duty truck that is consistently operational (e.g. three shifts per day) and rarely stationed.
Production/refilling station: a station that produces or dispenses roughly the same amount of hydrogen as is demanded by its customer(s) on daily/weekly/monthly basis.
OEM: Original equipment manufacturer: in automotive, a company that sells an entire vehicle.
OVER-THE-ROAD: Long-distance trucking, where drivers do not return to their base at the end of their shift.
PARASITIC LOAD: In trucking, parasitic or auxiliary load refers to power consumed by additional equipment installed on the vehicle, such as trash compactor, refrigeration unit, concrete mixer, etc. These vehicles use more fuel, as it is used both to propel the vehicle and operate the equipment.
PAYLOAD: The weight of the goods that are being delivered by the commercial vehicle.
The trucking industry is structured to pay based on the amount of goods that are moved. There is a limit on how much weight a truck can move, which includes the weight of the truck itself.
TCO: “Total Cost of Ownership” — The total cost of ownership of a vehicle over the course of its lifetime. This includes the vehicle itself, fuel, maintenance, service, parts, and repair.
Technology
ELECTROLYSIS: The process of using electricity to split water into hydrogen and oxygen.
ENERGY DENSITY: The amount of energy stored in a single unit, generally expressed as volume or mass.
A fuel with high energy density will be able to store a lot of energy in a small amount of mass. In a fuel cell vehicle, hydrogen provides energy storage, determining energy density.
FEEDSTOCK: Any material that can be used to make hydrogen. For Hyzon, this generally includes waste (biomass, methane, landfill), renewable natural gas, solar, and wind.
FUEL CELL: A fuel cell is comprised of layers through which hydrogen and oxygen are funneled to produce electricity. Each FCEV has many of these individual layers — the accumulation of which is called the fuel cell stack.
FUEL CELL STACK: Many fuel cells stacked together, with necessary housing components.
FUEL CELL SYSTEM: The fuel cell system includes the fuel cell stack and all necessary components to funnel hydrogen and oxygen to the fuel cells, water to the “tailpipe,” and electricity to the motor. Useful analogy:
Fuel cell -> single Christmas tree light
Fuel cell stack -> string of Christmas tree lights
Fuel cell system -> string of Christmas tree lights with extension cord to reach outlet
MEA: “Membrane Electrode Assembly” — The heart of a fuel cell. It is here that hydrogen and oxygen are combined to produce electricity – which is funneled to the motor — and water.
POWER DENSITY: The rate at which energy is transferred when generated (e.g. through propulsion, heat, electromagnetic current), divided by the weight of the generator.
Power density can be thought of as the amount of power a generator has to produce to move itself. If generator A produces the same amount of power as generator B, but only weighs half as much, it has twice the power density. In a fuel cell vehicle, the fuel cell system acts as the generator, determining power density.