Last modified: Jan 27, 2024

Climate System

Climate systems in cars refer to the HVAC (Heating, Ventilation, and Air Conditioning) systems that are designed to regulate the temperature, humidity, and air quality inside the vehicle cabin for passenger comfort.

These systems typically consist of various components, including a heat pump, which play a crucial role in providing a comfortable cabin environment.

Number of Zones

Modern car climate systems often have multiple zones, typically referred to as “zones” or “dual zones.” A single-zone system provides the same temperature and airflow for the entire cabin, while a multi-zone system allows for individual temperature and airflow control for different sections of the vehicle, usually the driver and front passenger sides. In some advanced systems, there may be additional zones for rear passengers as well, providing greater customization and comfort.

Skoda 3 zone climate system

The zone setups typical available are

  • 1-zone (whole cabin as one)
  • 2-zone (left and right front)
  • 3-zone (left and righ front + second row)
  • 4-zone (left and right front + left and right second row)

Vents

HVAC vents in cars are an important part of the vehicle’s climate control system. They are designed to distribute conditioned air, whether heated or cooled, to various parts of the passenger cabin to provide a comfortable environment for the occupants. Here are some key points about vents for HVAC in cars:

Volvo EX90 Air Vent

Types of Vents: Most modern cars have a variety of vents located throughout the passenger cabin. These can include dash vents, floor vents, rear-seat vents, and defrost vents. Dash vents are usually located on the dashboard and direct airflow towards the face of the driver and front passenger. Floor vents are typically located at the base of the dashboard and direct airflow towards the feet of passengers. Rear-seat vents are usually located on the rear of the center console or in the rear of the vehicle, and they provide airflow to the rear-seat passengers. Defrost vents are usually located on the dashboard near the windshield and are used to defrost or defog the windshield.

Airflow Control: Most HVAC vents in cars have adjustable louvers or directional flaps that allow the occupants to control the direction of airflow. These can be manually adjusted to direct airflow towards the desired areas, such as the face, feet, or windshield, based on the preferences of the driver and passengers. Some vehicles may also have automatic airflow control, where the direction and intensity of airflow are automatically adjusted based on the climate control settings.

Modes of Operation: HVAC vents in cars can operate in different modes depending on the climate control settings. These can include heating mode, cooling mode, fan-only mode, or a combination of these modes. In heating mode, warm air from the engine coolant is directed through the vents to warm up the passenger cabin. In cooling mode, air from the air conditioning system is directed through the vents to cool down the passenger cabin. Fan-only mode circulates air from the cabin without heating or cooling it, which can be useful for air circulation or ventilation purposes.

Control

HVAC (Heating, Ventilation, and Air Conditioning) control in cars refers to the system that allows the driver and passengers to adjust and regulate the temperature, airflow, and other climate control settings inside the vehicle. Here are some key points about HVAC control in cars:

Control Panel: Most modern cars have a control panel typically located on the dashboard or center console that allows the driver and passengers to adjust the HVAC settings. The control panel usually includes various knobs, buttons, or touchscreens that enable control over the temperature, fan speed, air distribution, and other settings.

Temperature Control: The temperature control allows the driver and passengers to adjust the desired temperature inside the vehicle. It can be adjusted using a temperature dial, buttons, or a touchscreen. The temperature control may also have dual-zone or multi-zone capability, allowing different temperature settings for the driver and passengers in different areas of the vehicle.

Fan Speed Control: The fan speed control allows the driver and passengers to adjust the speed of the blower motor, which determines the airflow inside the vehicle. It can typically be adjusted using a fan speed dial, buttons, or a touchscreen. The fan speed can be set to different levels, from low to high, to control the intensity of airflow.

Air Distribution Control: The air distribution control allows the driver and passengers to control where the conditioned air is directed inside the vehicle. It can typically be adjusted using buttons, knobs, or a touchscreen. Air distribution options may include dash vents, floor vents, rear-seat vents, and defrost vents, which can be individually adjusted or set to automatic mode.

Mode Selection: The mode selection control allows the driver and passengers to choose between different modes of operation for the HVAC system. Common modes may include heating mode, cooling mode, fan-only mode, or a combination of these modes. These modes determine how the HVAC system operates and the type of conditioned air that is delivered to the cabin.

Other Controls: Some vehicles may have additional controls for features such as recirculation mode (which controls whether the system recirculates cabin air or draws in fresh outside air), defrost mode (which directs air to defrost or defog the windshield), and rear-window defogger (which activates the rear-window defogger grid for clearing fog or frost).

Automatic Climate Control: Most modern vehicles also feature automatic climate control, which uses sensors and algorithms to automatically adjust the HVAC settings based on the desired temperature, outside temperature, humidity, and other factors. Automatic climate control can provide a more convenient and consistent cabin comfort experience, as it can automatically adjust the HVAC settings to maintain the desired temperature without constant manual adjustments.

Heat Pump

Some Evs have heat pump systems. It is not a specific component of a car’s climate system but a collection of various components that together makes a heat pump system responsible for heating or cooling the air that is circulated into the cabin.

It uses the principles of thermodynamics to transfer heat from one location to another, either from the outside environment to heat the cabin during cold weather (heating mode), or from inside the cabin to the outside environment to cool the cabin during hot weather (cooling mode).

Heat pumps are more energy-efficient than traditional resistive heating methods, as they can transfer heat rather than generating it, making them a more eco-friendly option.

Heat pumps work by using a refrigerant, which is a type of fluid that can change state from liquid to gas and vice versa, to absorb heat from one location and release it in another.

In heating mode, the refrigerant absorbs heat from the outside air, even in cold temperatures, and then compresses it to increase its temperature before releasing it into the cabin as warm air. In cooling mode, the heat pump absorbs heat from the cabin air, compresses the refrigerant to increase its temperature, and then releases it to the outside environment as hot air, effectively cooling the cabin.

In Evs some manufacturers take the waste heat from the electric drive (inverter and electric motor) and also the high-voltage battery can be used to heat the interior. This reduces drastically the draw on battery power for the heating system, thus increasing the range.

Components that are used to draw heat from are

  • Motor(s)
  • Inverter(s)
  • DC to DC converter
  • AC to DC converter
  • Battery

Mercedes EQE Suv heatpump reuses heat from battery and motors in to the cabin

Heat pumps in car climate systems are designed to be efficient and effective in various weather conditions, providing reliable heating and cooling performance regardless of the outside temperature. They are commonly used in electric and hybrid vehicles due to their energy-efficient operation, which helps extend the driving range by reducing the load on the battery.

Infrared heating

EV manufacturers like BWM and Lexus have introduced infrared heating to reduce consumption need for regular HVAC.

On the Lexus RZ450 panels installed beneath the steering column and the left-hand side of the instrument panel use infrared heating to warm the driver and front passenger’s legs directly. Delivering heat only where it is required reduces the load on the air conditioning system and helps preserve the vehicle’s driving range. Compared to a standard climate control system, energy consumption is reduced by around eight per cent.

Lexus RZ450 Radiant heating

Surface heating

Seat belt heating

The automitive supplier, ZF has created a heated seat belt that could reduce energy consumption.

Power consumption and affect on EV range

The power consumption of a car’s climate system depends on various factors, including the type of system, the outside weather conditions, the desired temperature settings, and the overall efficiency of the system. Generally, the climate system is one of the major energy consumers in a vehicle, and its power consumption can vary widely.

In electric vehicles (EVs) and plug-in hybrid electric vehicles (PHEVs), the climate system is powered by the vehicle’s battery, which provides electrical energy for heating, cooling, and ventilation. The power consumption of the climate system in EVs and PHEVs can have a significant impact on the vehicle’s driving range, as it draws power from the same battery that powers the electric motor. The power consumption of the climate system in EVs and PHEVs depends on factors such as the outside temperature, desired temperature settings, fan speed, and overall efficiency of the system.

Advanced climate systems with features such as multi-zone temperature control, seat heating/cooling, and defrosting can consume more power compared to basic systems with single-zone control and standard features. Additionally, running the climate system at higher fan speeds or lower temperatures can also increase power consumption.

So how much can it affect the range of an EV?

The most powerful HVAC system can pull up to 10KW power. This time of energy consumption is typical only needed for a short time when heating a cold car to comfortable temprature. When a car is heated up the consumption typical varies between 1-5KW on average depending on temprature.

So how much does that affect range.

ScenarioBases consumptionHeatingRange change
Tesla model 3 LR WLTP cyclus12.5kWh/100km2KW-25.6%
Mercedes EQS SUV 58017.8kWh/100km2KW-19.5%%

Most sold EVs globaly

Below, you find the top 10 most-sold EV models in the world. Click on the name for full info.