Rural lighting
Practical Action
watt) can vary considerably between different products. There can also be a high degree of
variation within individual batches of products.
The number and configuration of the diodes will vary between different lamps. The light from
WLEDs is very directional which is not always best suited for general lighting in a room; reflective
lampshades can improve the situation.
One of Practical Action’s projects in Nepal promoted WLED lamps incorporating 3 diodes and
rechargeable batteries that were made by trained local community members in partnership with
Krishna Grill & Engg. (P) Ltd., a local manufacturing company.
Light up the World, another organisation that promotes lighting to poor rural communities in
Nepal using WLEDs, used simple hand-powered generators to power the low-energy lighting
systems in remote parts of the country.
For practical purposes, the options for lighting reduce generally either to lamps that run on fuels,
or electric lights. Table 1 indicates the options and their relative lighting capability.
Type of light
Energy source
Intensity
(lumens)
Efficiency
(lumen/W)
Candle
Paraffin wax
1 0.01
Oil lamp (wick)
Hurricane lamp (wick)
Kerosene
Kerosene
1-10
10-100
0.01-0.1
0.1-0.2
Oil lamp (mantle)
Kerosene
1000
1
Gas lamp (mantle)
1.p.g (e.g. butane or
biogas)
1000
1
Filament lamp 3W
Filament lamp 40W
Electricity
Electricity
10 3
400 10
Filament lamp 100W
Electricity
1300
13
Fluorescent 15W
Fluorescent 30W
Electricity
Electricity
600
1500
40
50
Mercury
80W
Electricity
3200
40
Sodium sox 35W
Electricity
4500
128
White Light Emitting Diode 1W
Table 1: Lighting capacity
Electricity
25 - 50
25 - 50
More important to the user than the efficiency in lumen/watt is the cost per lumen, however, this
is difficult to determine as prices will vary depending on where items are purchased and on the
quantity bought as well as the actual life of the item.
Wicked lighting options such as kerosene lamps and candle wax are often the cheapest sources of
watts which partially makes up for their inefficiency, but not for their poor quality light. Kerosene
pressure lamps produce better light, but they are unpleasantly noisy and uncomfortably hot to be
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