Overview of energy-efficient lighting technologies: compact fluorescent lamps, halogen lamps, sodium vapor lamps, LED lamps, fluorescent lamps, tubes
Following an analysis of the characteristics of new types of light bulbs with the criteria to optimize savings and emissions.
Let's first two short considerations:
Home lighting has a significant weight on energy consumption: the annual share of electricity consumed in Italy is higher than 7 billion kilowatt-hours, corresponding to around 13% of the total consumption of electricity in the domestic sector and 80% lighting is outdated and inefficient.
The member countries of the European Union, to reduce environmental impact and energy consumption, in 2009 banned the products progressively less efficient, requiring compliance with the energy efficiency classes A, B and C, where the old incandescent bulbs are classified as D, E or F.
One of the most important parameters in the selection of energy saving light bulbs is that the luminous efficiency is expressed in lumens / watt: the parameter defined by the ratio between the luminous flux (in lumens) and the electrical power consumption (in watts) . This parameter defines the performance and energy consumption below. For example, the old incandescent bulbs, the most widespread civil have a very low efficiency: a 150-watt light bulb emits about 2,000 lumens, or 2.000:150 = 13 lumens per watt absorbed.
Fluorescent lamps have a high luminous efficiency and are divided into tubular and compact and have a good color rendition. They contain small amounts of mercury and should be disposed of with this collection.
The tubular lamps have a luminous efficiency which varies from 50 to 120 lumen / Watt, an average life that ranges from 10,000 to 24,000 hours and are indicated for prolonged illumination. Energy saving is on average 75% compared to that of the old lamps but you need a power supply because they are not directly connected to the mains.
The compact fluorescent lamps have a luminous efficiency of 50 to 75 lumens / watt and can reduce about 70% of the consumption of electrical energy than incandescent lamps with luminous flux (from a 20-25 watt when replacing one from 100 watts). Have a duration that varies from 6,000 to 15,000 hours, depending on the type and use, and meet the energy classes A and B. In the marketplace, we can find in various shapes and sizes and meet the requirements both at home and professionally.
Halogen bulbs, from the environmental point of view contribute to reducing emissions of greenhouse gases, have a good luminous efficacy (15-25 lumens / watt), consume 30% -50% less than traditional bulbs and have a average life around 2,000 hours. The requirements are those that meet the efficiency classes D, C and B and a crisp, white light with excellent color rendering. There are two types: a low voltage, that require a transformer, and a voltage in the network, which can be installed directly.
The sodium vapor lamps have a high luminous efficiency, and there are those at high pressure have a luminous efficiency of 70-150 lumens / watt and an average life of 12,000 to 20,000 hours, and those at low pressure, which have a 'greater efficiency, 125-200 lumens / watt. Both are mainly used for street lighting and damage cost in operating phase, in which, however, is not required quality to the light emitted.
In the field for external (for example the light of traffic lights) and interior are spreading more and more the use of LED (Light-Emitting Diodes, light emitting diodes), because of their high luminous efficiency, durability and savings energy. Their efficiency is equal to compact fluorescent lamps, 50-60 lumens / watt (120 lumens / watt for those of last generation), but have a longer life (up to 100,000 hours). They also do not contain mercury or lead and may be disposed of in the waste.
I emphasize, however, that this future technology is still expensive and not shines brightly environment, besides the fact that the Ministry of Health has assessed the question of the possible risks arising from their use, with the consequent willingness to support an in-depth technical regulations: the 'creation of systems that do not allow direct viewing of the light beam emitted by the LEDs to prevent glare and inspection of equipment placed on the market.
20/12/2011
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Translated via software
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Source:
Italian version of ReteIngegneri.it