Lighting

Energy Needs for Lighting

Unlike heating or cooking, lighting is one of the energy end uses that is often associated exclusively with electricity. But the reality is different: In fact, about a third of the world’s population uses fuel-based lighting.

Every year, African households and small businesses spend upwards of $17 billion on lighting, dominated by fuel-based sources such as kerosene, a costly an inefficient alternative. However, despite these huge expenditures – many households spend as much as 30% of their disposable income on fuel-based lighting – consumers receive little value in return. Fuel-based lighting is inefficient, provides limited and poor quality light, and exposes users to significant health and fire hazards. Exacerbating this problem, fuel-based lighting also produces Greenhouse Gases (GHGs), leads to increased indoor air pollution and associated health risks, inhibits productivity and jeopardizes human safety.

The state of affairs concerning fuel-based lighting is worrisome. Oil import dependency is generally high in developing countries, and it drains valuable hard currency. Further complicating the picture, subsidized kerosene intended for domestic lighting sometimes finds its way into vehicles, which creates additional environmental consequences.
Meanwhile, electrification (for lighting and other energy services) has its own problems, not the least of which is the extraordinary cost of electric transmission and distribution costs and low system efficiencies associated with providing centralized power generation in such conditions. A further limitation is the high cost for families buying electrical appliances and setting up electrical circuitry in their homes.

There are a wide variety of fuelbased light sources, including candles, oil lamps, ordinary kerosene lamps, pressurized kerosene lamps, biogas lamps, and propane lamps. According to most studies, ordinary kerosene lamps are the most common type of fuel-based lighting in developing countries. The more efficient kerosene lamps tend to increase both light output and fuel consumption, whereas an efficient electric compact fluorescent lamp provides an eight-fold reduction in primary energy consumption compared to standard incandescent light sources. According to a 1995 study, typical household kerosene lamp use is 3 to 4 hours per day, with weekly fuel consumption of about 1 litre. Typical light outputs are 10 to 15 lumens for locallymade lamps and 40 to 50 lumens for store-bought models. Placed in perspective, the lower end of this range corresponds to about 1% of the light produced by a typical 100-watt incandescent lamp.

A study conducted by the joint UNDP/World Bank Energy Sector management Assistance Programme (ESMAP) found rural households spending as much as US$10 per month on lighting from candles, kerosene and dry cell batteries. This operating cost is similar to that paid by industrialized households with two dozen bright electric light sources throughout their home.

Many suppliers of energy-efficient lighting equipment have not found the rural markets in developing countries worth exploring. However, the large amounts of money spent on lighting fuel indicates that there is a considerable potential for spending money on alternatives, for instance PV-based lighting solutions; this was verified in a field test by the World Bank.

Between 15 and 88 billion litres of are consumed each year to provide residential fuel-based lighting in the developing world. The primary energy consumed for this fuel-based residential lighting is between 13% and 78% of that used to provide the approximately 400 TWh of electricity consumed for residential electric lighting globally. The cost of this energy ranges from $15 to $88 billion/year (assuming a kerosene price of $1/ litre), or $44 to $175 per household. The amount of light (measured in lumen hours) is approximately 1/1000th that enjoyed by households in the industrialized world (more sources; more efficient sources).

Among the more startling implications of these findings is that users of fuel-based lighting in the developing world spend as much or more money on household lighting as do households in the industrialized world, but receive a vastly poorer level of service. On a percentage-of-income basis, households in developing countries spend many times more for lighting than their counterparts in the industrialized world.

Some argue that the problem of fuel-based lighting is not a priority, given the environmental impacts and costs of other end uses, such as cooking. However, few would dispute that improving the quality and quantity of light available to households in the developing world would yield dramatic social and health benefits.

References:
Mills, E. (2000): Fuel for Lighting - an Expensive Commodity. Boiling Point 45. http://www.hedon.info/FuelForLighting-AnExpensiveCommodity .
Lighting Africa: About Us. http://www.lightingafrica.org/node/23 .

Meeting Energy Needs for Lighting

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