DELP (UJALA) Scheme – Comparison: LED – CFL – Incandescent Bulb
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Domestic Efficient Lighting Programme (DELP) or Unnat Jyoti by Affordable LEDs for All (UJALA) scheme
Bachat Lamp Yojana
- “Bachat Lamp Yojana” was a launched in 2009 to reduce the cost of compact fluorescent lamps (CFLs, i.e., energy saving lights) sold to consumers.
- Implemented through the Bureau of Energy Efficiency (BEE) in India’s Ministry of Power, the program’s goal was to deliver CFLs at the cost of normal lightbulbs.
- The difference in cost will be covered by the sale of Certified Emission Reduction(CER) Units (Carbon Credits) under the Clean Development Mechanism of the Kyoto Protocol.
- The Ministry of New and Renewable Energy stopped the subsidy on CFL-based solar lighting system to encourage the use of the LED version.
DELP
- DELP replaced the ‘Bachat Lamp Yojana’ [Energy Efficient Lighting Programme (EELP)] – Scheme to offer CFL at the price of Incandescent bulbs.
- DELP encourages the people to use LED bulbs in place of incandescent bulbs, tube lights and CFL bulbs.
- DELP sold 9 crore LED bulbs at subsidized prices reducing the energy cost by 50 billion rupees.
- DELP scheme is implemented by Energy Efficiency Services Limited (EESL) – Ministry of Power.
EESL
- EESL is a Joint Venture company of four Central Power Sector undertakings viz. NTPC Ltd, PFC, REC, and Power Grid.
- EESL was set up to create and sustain markets for energy efficiency in the country.
- EESL works closely with the Bureau of Energy Efficiency (BEE).
- It is leading the market related activities of the National Mission for Enhanced Energy Efficiency (NMEEE), one of the 8 national missions under National Action Plan on climate change.
Comparison: Light Emitting Diodes (LEDs) – Incandescent Light Bulbs – Compact Fluorescents (CFLs)
Tungsten Lamp or incandescent light bulb
- In an incandescent light bulb, a wire filament (tungsten) is heated to a high temperature by passing an electric current through it until it glows with visible light.
- The hot filament is protected from oxidation with a glass or quartz bulb that is filled with inert gas.
Why tungsten?
- Pure tungsten has very high melting point (3400 °C) [An electric current can heat the filament around 2000-3000 °C, which stays below the melting point of tungsten].
- It has very low vapor pressure, and greatest tensile strength out of all the metals.
CFL
- Compact fluorescent lamp is a fluorescent lamp designed to replace tungsten lamp.
- Compared to incandescent lamps, CFLs are highly energy efficient.
- Like all fluorescent lamps, CFLs contain toxic mercury.
Fluorescent lighting
- A fluorescent lamp is a low pressure mercury-vapor gas-discharge lamp.
- Electrons that are bound to mercury atoms are excited to states where they will radiate ultraviolet light as they return to a lower energy level.
- This emitted ultraviolet light is converted into visible light as it strikes the fluorescent coating on the bulb (phosphor coating).
LED lamp
- An LED lamp is a light-emitting diode (LED) product which is assembled into a lamp.
- LED lamps have a lifespan and electrical efficiency which are several times longer than incandescent lamps, and significantly more efficient than most fluorescent lamps.
Light-emitting diode (LED)
- A light-emitting diode (LED) is a two-lead semiconductor light source.
- It is a p–n junction diode, which emits light when activated.
- When a suitable voltage is applied to the leads, electrons are able to recombine with electron holes within the device, releasing energy in the form of photons.
- This effect is called electroluminescence, and the color of the light corresponds to the energy of the photon.
Comparison: Light Emitting Diodes (LEDs) – Incandescent Light Bulbs – Compact Fluorescents (CFLs)
Type | ![]() |
![]() |
![]() Light Bulbs |
Life Span (average) | 50,000 hours
40X |
8,000 hours
7.5 X |
1,200 hours
X |
Power used | 7 watts
X |
14 watts
2X |
60 watts
9X |
Brightness in lumens | 600 | 540 | 800 |
Annual Operating Cost | X | 2X | 10X |
Contains the TOXIC Mercury | No | Yes | No |
Carbon Dioxide Emissions
(The bulbs don’t emit CO2. Power generation emits CO2.) |
X | 2X | 10X |
Turns on instantly | Yes | No – takes time to warm up | Yes |
Heat output | Low | Medium | High |
Heat sensitive | No | Yes | Yes |
Moisture sensitive | No | Yes | Yes |
Durability | Very Durable – LEDs can handle jarring and bumping | Not Very Durable – glass can break easily | Not Very Durable – glass or filament can break easily |
Source: http://goo.gl/255fPE and Delp Scheme.
Insulated gate bipolar transistor (IGBT)
- A transistor is a semiconductor device.
- It forms the basic component of all electronic devices.
- It is used to amplify or switch electronic signals and electrical power.
- IGBT replaces analogue power control with digital power control with a massive increase in efficiency.
IGBT applications
- A CFL lamp needs a switch. IGBT plays the role of a switch in a CFL.
- IGBTs is also used to generate the (mercury) gas discharge, which lights up the bulb.
- The IGBT’s other advantage is that it can fit in a small volume.
- IGBT are also used in electronic components of various household appliances ranging from space heaters to refrigerators.
- They are also used in medical products (X-ray, CAT, MRI).
Jayant Baliga
- Inventor of the insulated gate bipolar transistor (IGBT).
- Alumnus of Indian Institute of Technology, Madras.
- He won the global energy prize in 2015.
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