PH4019Shatin Tsung Tsin Secondary School

Project Holders: Fan Chun Kit (Felix) Hui Chun Kit (Gibson) Li Miu Yin (Winnie) Sze Kam Fung (Sam)

40th Joint School Science Exhibition Competition

Scientific solutions for the green revolution

Our problems

-Problems we are facing now

-Pollution

-Global warming

-Energy Crisis

Our target

-Reduce the use of electricity by using

-Auto lighting system

-Air directing system

-Solar-heating system

Auto lighting system

Aims

- Reduce extra lighting

- Maintain a comfortable lighting environment

Auto lighting system

Model

Auto lighting system

Components1. Sensors2. Control Unit3. LED Lighting

- LED- Frame- LED Driver

4. Blinds and motor

Auto lighting system

Sensors

-Detect light intensity

-Put at different positions

Auto lighting system

The Control Unit

- Implements negative feedback

- Controls lighting

Auto lighting system

LED Lighting- LED- Frame- LED Driver

- High efficiency- No Heat Produced- No UV and infra red- Long lifespan

Auto lighting system

Blinds- Control sunlight

- Reduce heating effect

Motor- Control the blinds

Auto lighting system

Condition 1 The light intensity is too high

The lighting becomes dimmer

Working principle

Auto lighting system

Condition 2 The light intensity is too low

The lighting gets brighter

Auto lighting system

Condition 3 The light intensity is extremely high

The motor will lower the blinds

Air directing system

Aims

- To maintain a comfortable temperature in an office

- Save energy for air-conditioning

Air directing systemModel

Air directing system

Components1. Sensors2. Control Unit

- Manual modulator3. Fan4. Deflectors5. Motors6. Paper strips

Air directing system

Sensors

Movement of the deflectors

- Each sensor will control only half of the deflectors

Air directing systemControl Unit

- Negative Feedback

~used to maintain a comfortable temperature in an office

- Manual modulator

~allow people to adjust the set temperature as they want

Air directing systemFan, deflectors and motors

-Fan and deflectors are installed in the air outlet

Air directing systemFan

-Control the speed of the air flow

Deflectors

-Facilitate air flow

-Control air flow in local areas

Motors

-used to swing the deflectors to an appropriate position

Air directing systemPaper strips

- use to show the direction of the air flow

Air directing systemWorking principle

(T= Temperature sensed by one sensor, S= range of set temperature)Condition 1: T > Upper bound of S~The deflectors will be swung to the position of the sensor by the motors

Air directing systemWorking principle

(T= Temperature sensed by one sensor, S= range of set temperature)Condition 2: T < Lower bound of S~The deflectors will be swung and closed

Air directing systemWorking principle

(T= Temperature sensed by one sensor, S= range of set temperature)Condition 3: All T < Lower bound of S ~ the speed of fan will be decreased or even stopped

Condition 4: All T> Upper bound of S ~ the speed of the fan will increase

Solar Pantry

Aims- To reduce the use of electricity for heating water as much as possible

- To implement a clean and renewable energy source

Solar Pantry

Light source

Solar Panel

Model

Rubber tubing

Water tankWindow

Solar Pantry

Components

1. Solar Panel

2. Rubber tubing

3. Water tank

4. Temperature sensor

Solar Pantry

Solar Panel

- Use solar energy for heating

- Dark surface

- Fluid circulation assisted by convection

Solar Pantry

Water tank

- Double- layered- Inner layer Spiral shaped, Metal coated

- Outer layer Water circulation

Solar Pantry

Temperature sensor

- Detect water temperature- If the temp of heated

water detected < Set temp,

conventional heating

would be carried out

- Else, cool water would

be released

Solar Pantry

Water in

Light source

Solar Panel

Temp. sensor

Rubber tubing

Water tank (Heat exchange occurs)

Heater

Cool water

Mixing tank

Solar Pantry

Convection current

Heated water

Cooler water Water with

desired temp

The End