Advanced Vehicle Systems
NREL researchers test batteries developed for hybrid electric vehicles.
Advanced vehicles—such as plug-in hybrids and fuel cell vehicles—can be quite different from conventional vehicles. Therefore, they require different vehicle systems. These systems and their components not only help make these vehicles more fuel efficient but also can help reduce tailpipe emissions.
Advanced vehicle systems that NREL works on include:
Vehicle Energy Storage
Batteries are the most common type of energy storage devices. For example, the batteries in cell phones and laptops store energy, so we don't have to keep them plugged into an electrical outlet. Conventional vehicles use a lead acid battery to start their engines and power other electronics, such as the lights. Hybrid electric vehicles and fuel-cell vehicles use lead acid batteries but also batteries that propel them or move their wheels. To learn more, see information about vehicle batteries.
Another type of energy storage device is an ultracapacitor. Ultracapacitors can provide additional power for acceleration or climbing a hill. To learn more, see information about vehicle ultracapacitors.
Also learn more about NREL vehicle research in energy storage.
Vehicle Power Electronics
Many things we use everyday—from computers to microwave ovens—use power electronics. Basically, power electronics control the flow of electricity via electronic power devices. In vehicles, these devices include:
- Electronic ignitions
- DC (direct current) to DC converters
- Inverters
- Motor controllers.
Hybrid electric vehicles and fuel cell vehicles rely on power electronics to determine the exact nature and timing of electric power to their motors.
To learn more, see information about vehicle power electronics. Also learn more about NREL vehicle research in power electronics.
Vehicle Thermal Comfort
After we start our engines, we usually try to make ourselves comfortable by setting the temperature inside the vehicle. We roll down the windows, turn on the heater, or turn on the air conditioner. This is called thermal comfort.
For thermal comfort, air conditioning in particular can consume a considerable amount of fuel. NREL works to develop more efficient air-conditioning systems, which can include one or more of the following vehicle cooling technologies:
- Ventilated seats
- Cabin insulation
- Advanced window systems
- Parked car ventilation (solar powered).
NREL researchers are even exploring heat generated cooling. This counterintuitive approach uses waste heat from the engine to cool the vehicle. See heat generated cooling for more information.
To learn more about NREL research in energy-efficient thermal comfort systems, see information on vehicle ancillary loads reduction.
Vehicle Systems Analysis
Vehicle systems can be evaluated for:
- Fuel efficiency
- Tailpipe emissions
- Performance
- Sizing
- Component cost.
Using computer simulations, systems can be evaluated before they're used in a vehicle. And they can be evaluated after they're installed. NREL researchers also evaluate how different types of systems—energy storage, power electronic, and thermal comfort—work together in a vehicle. This can even include how they work with different alternative fuels and driving behaviors.
Entire fleets of trucks and buses can be evaluated too. For more information, see fleet test and evaluation.
Learn more about NREL's vehicle systems analysis.
For information about advanced vehicle systems research and development, also see the U.S. Department of Energy Vehicle Technologies Program.
