Compact Fluorescent Lamp (CFL) technology provides a low energy lighting service through the use of a compact fluorescent light bulb that replaces the normal Tungsten filament  light bulb. Still, there is a whole range of different sorts of lamps from ordinary incandescent tungsten filament bulbs to Tungsten Halogen, Halogen infrared reflecting, Mercury vapour lamps, Compact fluorescent lamps, linear fluorescent, metal halide, compact metal halide, high pressure sodium (High Intensity Discharge HID lamp) and Light Emitting Diodes (LED) . CFLs contribute to security of energy supply as they make a significant contribution to reduction in electricity demand. The higher up-front cost could be a barrier for their implementation, but calculations show that CFLs pay back the initial investment within 900 hours of operation and also contribute to a reduction in the electricity bill over the lifetime of the bulb. The savings can be in the order of 10-20 times the initial cost over the life of the bulb.
Lighting entails greenhouse gas emissions of 1 900 Mt of CO2 per year, equivalent to 70% of the emissions from the world’s light passenger vehicles. The demand for artificial light is far from being saturated (IEA, 2010). A number of already fully commercialised technologies could significantly reduce lighting demand. They include incandescent, fluorescent and high-intensity discharge lamps; the ballasts and transformers that drive them; the luminaires in which they are housed; and the controls that operate them.
Compact Fluorescent Lamp (CFL ) technology provides a low energy lighting service through the use of a compact fluorescent light bulb that replaces the normal Tungsten filament light bulb. They have a variety of shapes and end fittings for use in all types of fitting. CFL bulbs are now designed to fit almost all light applications and devices but are particularly suitable for area lighting. In horticulture there is a demand for lights for growing plants. Figure 1 shows various kinds of CFLs available.
An example in the UK sold under the trade name ‘Envirolite’ is mainly used for propagation and vegetative growth (blue) purposes. However, there is an increase in use of flowering stage (red) Envirolites.CFLs operate in the same way as a fluorescent strip light. The inside of the bulb is coated with a phosphor. Electricity discharging through the bulb excites a small amount of mercury vapour in an inertgas such as argon or neon which results in UV light  emission. This UV light is at the correct energy level to cause the phosphor coating to produce light. There is an electronic ballast to start the lamp operating. An electronic ballast uses electronic solid state circuitry to provide the proper starting and operating electrical condition to power one or more fluorescent lamps. CFLs are called low-energy lamps because they use less energy than the traditional tungsten filament bulbs. A 20-25 W CFL will give an equivalent lighting service to a 100 Watt bulb.There used to be a perception that fluorescent lights use most of their energy in the start up phase but thiswas totally false. All lights should be switched off when not in use. Not only do they use less energy but also they last for longer: 8,000 hours compared to 500-2,000 hours. This means that it over its lifetime it pays for itself (between 500-900 hours depending on the electricity price) and provides substantial cost savings in energy use avoided over its lifetime.
An IEA (2006) report points out some of the factors preventing change to more efficient lighting alternatives. An important barrier is that there is no international standard that sets minimum quality and energy efficiency specifications for these lamps. According to IEA (2006), in the EU national standards for illumination in offices, schools, hospitals and shops range from 200 to 1500 lux. Obviously some sort of harmonisation is required and a move to lower lighting levels commensurate withavoidance of eye strain.
The experience from the programmes of CFL dissemination (GEF, 1998) shows that all of these actions are important, but that raising consumer awareness, international harmonisation of standards, quality improvement, effective distribution channels, and improving and enforcing bulb quality, and subsidy programmes are most important. The gains for people in overall cost terms and in minimising demand from a limited network are large. China already has a very large manufacturing base for CFLs as described above. Transfer of the technology has therefore already happened in the market and under some limited programmes and lessons can be learned from these.
Not all forms of lighting can substitute for all others. But large gains could be achieved, for example, from substituting lower-efficiency versions of a given lamp and ballast technologyfor higher-efficacy equivalents from within the same technology. Lighting technologies such as incandescent, tungsten halogen and high-pressure mercury are considered mature technologies with little room for increased luminous efficiency, whereas semiconductor (e.g. LED) and metal halide lamps are considered to offer high potential for further technical improvements. In the near term, however, the greatest gains from lamp changes are to be had from substituting new high quality CFLs for inefficient standard incandescent lamps, from phasing out mercury vapour lamps, and from using higher efficiency ballasts and linear fluorescent lamps (IEA, 2008). Still, the potential for market penetration of this technology is large, as the worldwide learning rate of CFLs is around 10% (IEA, 2010).
There are many voluntary initiatives worldwide to promote CFLs. To address market barriers for CFL deployment, the Efficient Lighting Initiative (ELI ) develops and promotes voluntary technical specifications that include rigorous technical and quality criteria. ELI has a labeling system that helps consumers identify energy efficient lighting products that meet the ELI specifications. ELI programs include marketing, educational, market building, and financing activities. Each participating country tailors its activities to meet the needs of the local market. These activities are supported by USD15 million in Global Environment Facility funding, and by additional local and international funding.
There are more than 30 billion electrical lamps worldwide. The technology is mature though there are other new developments in terms of lamps such as LEDs and HIDs. As there are no international standards, poor quality can be an issue in some areas. some support to develop a market is needed in order to minimise the effect of the relatively high up-front cost. The UNCTAD/Philips conference in Southern Africa about the feasibility of setting up amanufacturing base in SADC in July 2006 is a first step in exploring such a technology transfer (UNCTAD/Phillips, 2006). IKEA, one of the world’s largest furniture department store chains, with outlets in 28 countries, sells quality Chinese-made CFLs at low prices and others are following. China supplied 1 billion CFLs worldwide in 2004 representing about 75% of the world’s total (Global Sources, 2005). In Cuba, all ILs are exchanged to CFLs in 2007 in an effort to make the country energy efficient and self sustained and banned import and sales of incandescent light bulbs (see http://giri25.blogspot.com/2009/01/use-cfl-save-money-and-reduce-pollution.html ).
According to the IEA, lighting ranks among the major end-uses in global power demand. Lighting represents 650 mtoe of primary energy consumption and 2550 TWh of electricity consumption in 2005.This means that grid-based electric lighting is equivalent to 19% of total global electricity production. The statistics supplied by the IEA report (2006) shows that lighting requires as much electricity as is produced by all gas-fired generation or 1265 power plants. Of this amount the major consumption sector is commercial at 43% followed by residential at 31%, industrial (18%), and outdoor stationary sources at 8%.These statistics refer to on-grid sources. In developing countries, however, off-grid fuel based lighting isthe norm, for which, in 2005, 77 billion litres of kerosene and gasoline/diesel were used. The health risks associated with this are well known and the efficiency is low.
Vehicle lighting also comes under the ‘spotlight’ and is responsible for the consumption of 55 billion litres of gasoline/diesel in 2005. Solutions are available in the form of Xenon arc lamps which use 20% of theenergy for halogen headlamps and coloured LEDs for other applications.The report points out that the annual cost of non-mobile lighting including energy, lighting equipment and labour is USD 360 billion, which is roughly 1% of global GDP. Electricity accounts for some two thirds of this.
The biggest consumer is North America followed by Japan/Korea and then Australia/New Zealand before Europe and transitional economies. China and the rest of the world use less than 10% of the light service used in North America (relative to the USA lighting service demand of 1995 kWh/y, developing countries including China are around 180kWh/y). Nowadays, many cities in the USA are replacing theirincandescent traffic lights with LED arrays because the electricity costs can be reduced by over 80%.
A scenario analysis exploring the difference between implementing current policies and having none at all shows that current policies should lead to a difference in lighting energy consumption of 745 TWh in 2030. This would provide savings of USD 66 billion and 449 MtCO2 emissions. However, further improvements could be done.
As mentioned above they generate savings in energy costs over their lifetime and provide a reliable lighting service. They also generate jobs in manufacturing and retail. However, a safe disposal route is required. In developing countries, CFLs are recommended for use with PV systems as their energy demand is so much lower than incandescent bulbs. The problem of the higher up front cost could be overcome by, e.g., micro-credit systems, although the savings in electricity costs are substantial in the long term. As electricity supply is still limited in many developing countries, reducing demand by more efficient lighting is a positive step for their economies.
A market shift from inefficient incandescent lamps to CFLs would cut world lighting electricity demand by 18%. If end-users were to install only efficient lamps, ballasts and controls, global lighting electricity demand in 2030 would be almost unchanged from 2005, and could actually be lower between 2010 and 2030. This could be achieved at a global average negative cost of USD –161 per tonne of CO2 saved, but it would require strong policy action.
CFLs contribute to security of energy supply as they make a significant contribution to reduction inelectricity demand. The higher up-front cost could be a barrier for their implementation, but calculations show that CFLs pay back the initial investment within 900 hours of operation and also contribute to areduction in the electricity bill over the lifetime of the bulb. The savings can be in the order of 10-20 times the initial cost over the life of the bulb. Moreover, as CFLs market penetration has increased in the courseof time, the up-front cost has declined. For people in developing countries, however, programmes tomake CFLs more affordable will be needed in order to overcome the hurdly of relatively high investment costs. Technically speaking, the bulbs are now a proven, reliable technology for both on-grid and off-grid lighting.
Despite their many benefits, CFLs have some problems, including quality control at factories in developing countries. To address this issue, the Efficient Lighting Initiative (ELI), launched in 1999 by the International Finance Corporation and the Global Environment Facility, created a certification mechanism for high- quality products. There are some environmental problems associated with the bulbs which containmercury vapour, so that any programme on a large scale needs to be accompanied by a proper wasterecovery programme. This is covered by the EU Directive on Waste from Electrical and Electronic Equipment (WEEE), which requires manufacturers to have a system for disposal with deposits paid for the additional costs implied for collection, treatment, recycling and disposal of the waste.
The electricity used by lighting is also a major source of CO2 emissions. IEA (2006) estimatethat the emissions of CO2 from all lighting are 1,889 MtCO2 of which grid-based emissions are estimated at 1,528 MtCO2, fuel-based at 200 MtCO2, and vehicle-based at 161 MtCO2. All these emissions are equivalent to 70% of those from the world’s cars.
Analysis of a least life-cycle cost scenario involving more targeted substitution of low efficacy lighting was also carried out. This highlighted how lighting demand can be curbed at lower cost than continuing with current practices. The IEA report shows that by installing only efficient lamps, ballasts and controls, global lighting electricity demand would drop substantially and be almost unchanged from 2005 levels by 2030. It claims that “Following these measures would save more than 16,000 Mt of CO2 emissions overthe same time frame – equivalent to about 6 years of current global car emissions – and would avoid USD2,600 billion in total expenditure on lighting through reduced energy and maintenance costs”. A single CFL could contribute to CO2 emission reductions by 0.5 tonnes over the lifetime of the bulb. In the UK it has been estimated (IEA, 2005) that the potential savings from using CFL are 900 ktonnes CO2 over 10 years.
For calculation of these GHG emission reductions, it is recommended to apply the approved methodologies for demand side energy efficiency activities for specific technologies  and demand side energy efficiency activities for efficient lighting technologies  project (small scale activities) which has been developed under the Clean Development Mechanism of the UNFCCC Kyoto Protocol (CDM). This methodology helps to determine a baseline for GHG emissions in the absence of the project (i.e. business-as-usual circumstances), how emission reductions below this baseline can be calculated, and how these reductions can be monitored. General information about how to apply CDM methodologies for GHG accounting can be found at: http://cdm.unfccc.int/methodologies/PAmethodologies/approved.html .
The cost of a CFL has decreased markedly in recent years. As mentioned above the import of goodquality Chinese made bulbs has helped in this. However the larger up front costs are still a barrier andmore awareness in the public is needed on the overall cost savings to be gained. It has been shown (IEA, 2006) that the CFLs are cheaper and in fact produce cash savings over their lifetime as well as limit coststo society from climate change and investment in excess power station capacity.
While the purchase price of an integrated CFL is typically 3 to 10 times greater than that of an equivalent incandescent lamp, the extended lifetime and lower energy use will more than compensate for the higher initial cost. CFLs are extremely cost-effective in commercial buildings when used to replace incandescent lamps. Using average U.S. commercial electricity and gas rates for 2006, a 2008 article found that replacing each 75 W incandescent lamp with a CFL resulted in yearly savings of $22 in energy usage, reduced HVAC  cost, and reduced labor to change lamps. The incremental capital investment of $2 per fixture is typically paid back in about one month. Savings are greater and payback periods shorter in regions with higher electric rates and, to a lesser extent, also in regions with higher than U.S. average cooling requirements.
National government programmes and the Intelligent Energy Europe  programme with SAVE and ALTENER projects have contributed in supporting this technology. The IEA activities are also very important as theirrecent report shows (IEA, 2006) and in the USA many states are taking initiatives independent of theFederal Government.
The EU, however, limited the growth of Chinese CFL imports through the anti dumping tariff, whichcame into force in 2001 to avoid low quality bulbs flooding the European market. The WEEE Directivecould also act as a restricting influence on Chinese imports, but Worldwatch Institute (2006) expects it tostimulate them.
There are many programmes worldwide run by organisations such as the USH2O, REEEP, EUCOOPENER, UNFCCC/TTCLEAR and ADB Finesse project programmes. Several other programmes and projects can be found in Mexico, St Lucia and Asia. A range of organisations such as UNCTAD, GEF, IEA, REEEP and EU are facilitating these. UNCTAD hosted a conference in July 2006in Pretoria with Philips company to explore the feasibility of building a factory in the SADC region to make CFLs. It was also attended by the South African Government, City Power, Eskom and 11 SADC countries (UNCTAD/Phillips, 2006). There is no doubt that well designed programmes with subsidies to offset the up front costs of the bulbs are needed and can successfully change consumer preference for CFLs.
[this information is kindly provided by the UNEP Risoe Centre Carbon Markets Group ]
Project developers of energy efficiency in buildings projects in the CDM pipeline mainly apply the following methodologies:
The energy efficiency household projects are currently representing 0.1% of the CDM projects in the pipeline. Presently, there are six CDM projects registered in energy efficiency for households - four of them are based on lighting/insulation and two on improved stoves. The lighting/insulation projects are located in India and one in South Africa. The improved stove projects are based in Zambia and Nigeria.
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Worldwatch Institute, 2008. Strong growth in compact fluorescent bulbs reduces electricity demand. Available at: http://www.worldwatch.org/node/5920