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TAKEDA Global Warming Lab, Japan

Dramatic change of car air conditioner system into
“Low energy consumption type”
Greatly effective even for eco-friendly cars
You can expand the cruising range of electric vehicles (EV)．

Car mileage improved by 10% (in summer season)

Solar Radiation Control Plate

To be placed in the areas of a vehicle absorbing the most sunlight
　

AUTOMOTIVE INTERIOR MEMBER
Patent No.: US 8,047,598, B2
Date of Patent: Nov.1,2011

Registered Japan Patent No.: 4212636
　

Present problem　　　　　　　　　　　　　　　　　　　　　　　　　　

► When the car air conditioner is on, fuel consumption increases by about 40%.

It has been proven that almost all the above-mentioned load is actually created by “solar radiation coming through car windows”. The “Solar Radiation Control Plate” will greatly reduce heat which results from this solar radiation.

Performance of “Solar Radiation Control Plate”
(Most effective in summer season and sunny weather)

■ The product will block more than 70% of solar radiation heat.

The following are the advantages when the Solar Radiation Control Plate is installed on the dashboard and the rear window areas.

► Reduction of car air-conditioning load: 30%

► Improvement of car mileage: 10 %

► Decrease of heat in the front seats area: 7.2 degrees F (4C)

The heat coming from the dashboard is reduced to a negligible amount.

► Reduced glare in the front seats area: 30%

The glare reflected from the dashboard is reduced to almost nothing.

(Note) The above data was obtained using a 1500 cc-engine sedan type car.

■ Greatly effective even for eco-friendly cars

► Hybrid cars, electric cars etc.: Mileage and cruising distance can be improved.

■ The product can be used for any type of vehicle.
Ordinary cars, buses, trucks, taxis etc.

► Brand-new cars: The product can be installed /incorporated with original car interiors.
► Second-hand cars: The “Solar Radiation Control Plate” can be produced as a unit part, which can be installed anytime.

Examples of Problems and Advantages / Effects of product　　　　

► Problem: Mileage goes down when air-conditioner is used in summer season.

► Problem: On long drives, people reduce the time of air-conditioner usage to improve gas mileage.

► Problem: When a car is stopped for an extended period of time, keeping the air-conditioner on while the car is idling consumes a lot of fuel and therefore money. (e.g. taxis etc.)

► Problem: When a car is started after being parked for a long time, the temperature inside is usually quite high and it seems a waste to have to cool the air inside.

Advantage: Since this product reduces the cooling heat load of air conditioners, fuel consumption can be decreased.

► Problem: Since air-conditioning is seldom used except in the summer, we want to make the air-conditioner device smaller and lighter in order to improve gas mileage.

► Problem: Concerned about the cruising distance of electric automobiles, drivers of such vehicles tend not to use air-conditioning.

► Problem: When air-conditioning is used in hybrid cars, the decrease in gas mileage is very noticeable.

► Problem: Even cars used in areas where the annual number of days requiring air-conditioning is very small are still equipped with air-conditioning devices.

► Problem: When sunshine is very strong, even if the outside temperature is relatively low, air-conditioning is sometimes necessary.

► Problem: Since cool air produced from air-conditioning is often uncomfortable, some people avoid using it as much as possible.
　

Advantage: As this product blocks solar radiation heat to a great extent, the size of a car air-conditioning device can be reduced or air-conditioning may even become unnecessary.
　

► Problem: Strong sunshine makes the dashboard temperature very high, which produces heat in the front seats area.

► Problem: Bright sunlight reflected on the dashboard creates an uncomfortable glare for the driver.

Advantage: Since this product reduces absorption of solar heat and light to a great extent, temperature increase of dashboard and sunlight reflection on dashboard can be prevented.

► Problem: In order to prevent the so-called heat island phenomenon, we want to reduce car exhaust heat in urban areas.

► Problem: In order to prevent global warming, we want to reduce fuel consumption.
　

Advantage: By reducing the load of air conditioning, the amount of exhaust heat and CO2 emission is reduced.

　

Structure and function of “Solar Radiation Control Plate” (Figure 1 - 3)

The “Solar Radiation Control Plate” is an interior device which reduces the absorption of solar radiation heat and light coming through the windows.

■ Location of installation:
Install the product in the areas which get direct sunlight through the windows (such as the dashboard, the rear window area, etc.)

■ Structure & shape:
The “Solar Radiation Control Plate” is designed in a zigzag form with a specific angle. It consists of two sides: “The side which receives sunlight” and “The shady side”.

■ Function of reflecting the sunlight back through the windows:
The side which gets sunlight (No.1 slant face) is to be placed towards the windows so that the reflected sunlight will not hit the passengers.

■ Function of eradiating heat out of the windows:
This product will eradiate (back through the windows) the solar radiation heat from the side which gets sunlight, thereby decreasing the amount of heat absorbed.

■ Function of reducing radiation heat:
The shady side (No.2 slant face) is designed so as not to be hit by sunlight in order to
reduce radiation and therefore temperature.

■ Function of preventing heat affecting driver / passengers:
The shady side is to be placed towards the inside of the car so that solar radiation (heat and light) will not affect passengers.

■ Cooling function:
By bringing in outside air underneath the Solar Radiation Control Plate, the Plate is cooled down and the air will be vented outside the car after cooling down the Plate.

[Figure 1]　　　　　　　　　　　　　　　　　　　 [Figure 2]
　

[Figure 3] Detailed drawing of A part
　

(Note) Angle and height of zigzag form:
The size of the zigzag form can be altered if its angle conforms with the patent　　　　　　specifications.

[Explanation of symbols used in Figures]
1: vehicle      1a: inside vehicle      2: window (windshield)
3: interior device (dashboard)       4: interior device main unit
5: Solar Radiation Control Plate       6: surface receiving light
8: No.1 slant face   9: No.2 slant face   10: cool air pocket
12: air vent       13: fan
C: driver   R: sunlight    α: gradient angle of No.1 slant face (8)
β: gradient angle of No.2 slant face (9)

  Performance of “Solar Radiation Control Plate”　　　　　　　　　　　

(Measurements taken on dashboard area)
・ Targeted performance: The product’s effectiveness in reflecting and reducing the effect of heat and light resulting from solar radiation coming through the windows.
・ How to measure product’s performance: Measuring of data as below:
1. Data measured on the dashboard “without the Plate installed”.
2. Data measured on the dashboard “with the Plate installed”.
・ Vehicle used for measurement: 1500 cc-engine class sedan type car.
・ Time of measurement: On a sunny day in June with the sun directly shining on the car’s windshield.
・ Place of measurement: Tokyo and Osaka, Japan.

① Effect of reducing the amount of heat absorbed from solar radiation (See drawing below)
    Measuring method：By measuring the dashboard surface temperature which has risen because of
    solar radiation, the amount of heat absorbed is calculated.

② Effect of preventing temperature increase on dashboard (See drawing below)
Measuring method：Measuring the surface temperature of dashboard which has risen because of solar radiation. The Plate was cooled down by outside air while the car was in motion.

・ Outside air temperature: 26℃.　　Inside car temperature: 32℃. (while the car was in motion)

③ Effect of reducing heat in front seats area coming from dashboard. (See drawing below)
Measuring method：Place black board vertically on front seat (as if it were a passenger). Measure the surface temperature of the board, which has risen because of heat radiated from the dashboard.

⇒ the temperature in front seats area (drawing below)
Note: The Plate was not cooled down by outside air.

Effect: We feel almost no heat from the dashboard.

④ Effect of reducing glare from dashboard in front seats area (See drawing below)
Measuring method：Measure the brightness of sunlight reflected from dashboard in front seats area using an illuminometer.

Effect: Glare is negligible with the Plate installed.

Present problems resulting from solar radiation heat coming through car windows and effect of “Solar Radiation Control Plate”.

■ The problem: The amount of heat coming through the car windows is significant.

The data below show the areas of a car from which outside heat flows into the car and the heat quantity ratio of each part on sunny days in summer. The amount of heat coming into the car from outside is the actual load on the air conditioner. The total amount of radiation heat coming in through all the car windows (front, side and back windows) constitutes 73% of the total amount of incoming heat.

Vehicle used for measurements: 1500 cc-engine class sedan type car.

■ The problem: Car air conditioners are well known to consume a large amount of energy.

Presently all car air conditioners are used without reducing this great amount of solar radiation heat which comes through the windows. Because of this, air conditioners are extremely high energy consumers. When the air conditioner is in use, fuel consumption increases by about 40%. 　　　　　　　　　　　Source: The Energy Conservation Center, Japan

■ The effect of the “Solar Radiation Control Plate”
……is such that it should be installed in all vehicles in the world in order to achieve a low carbon society.

Since the effective performance of the “Solar Radiation Control Plate” reduces the heat from radiation coming through the windows by about 70%, when the Solar Radiation Control Plate is installed on the dashboard and rear window area of a vehicle, the vehicle’s cooling load is decreased by about 30% (in summer season, sunny weather). Car fuel consumption can also be lowered by about 10%.

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