Thermal management techniques are critical to the robust and efficient performance of conventional and electrified vehicles. Thermal management systems not only support reduction of emissions in absolute terms, but also contribute to reducing emissions variability for different driving conditions. (Powertrain thermal management technologies include active grille shutters, variable engine oil pumps, and active transmission warm-up; cabin thermal management includes passive cabin ventilation, reduced HVAC system loading, and heat pumps).
The ICCT is collaborating with automotive suppliers on a series of working papers evaluating trends and developments in passenger vehicle fuel-efficiency technologies. These papers extend and update the technology assessments performed by the US EPA and NHTSA to inform the 2017–2025 rule, which were conducted five years ago. Each paper evaluates:
- How the current rate of progress (costs, benefits, market penetration) compares to projections in the rule
- Recent technology developments that were not considered in the rule and how they impact cost and benefits
- Customer acceptance issues, such as real-world fuel economy, performance, drivability, reliability, and safety
The past decade has seen a proliferation of thermal management technological solutions (electric and variable mechanical pumps and control valves, active engine warm-up, active seat ventilation, etc.). As a result, automotive suppliers have been developing a host of new products to better manage powertrain and cabin temperature. The benefits of these new products may add up to 7.5% reduction in CO2 emissions and fuel consumption, depending on applied off-cycle credits and vehicle baseline.
Analyses for this report considered qualitative and quantitative factors (e.g., approximate market penetration, technical maturity, and cost per percent fuel consumption reduction), which are driving the application of thermal management advances.