Energy for rural communities
Practical Action
Stand-alone systems usually incorporate battery storage and have a 12v DC circuit. The
advantages of village electrification schemes using batteries include:
• The low-voltage battery excludes the danger of electric shocks within houses
• The battery technology is a relatively simple and well known, being applied in vehicles
throughout the world.
• Low load factor usage
The disadvantages include:
• The cost of electricity from rechargeable batteries can be very high
• Battery life can be short if not properly used and maintained
• They have a limited energy output which confines their use to lighting, radio and
other small appliances, which are not directly productive end uses
Another common practice for obtaining electricity is through pre-electrification battery
charging services. Remote energy systems cannot always supply power to all the households
wishing to receive it because of limited capacity or houses can’t afford the tariffs or the
connection charge.
This has resulted in the establishment of battery charging enterprises in which people can
take batteries, usually lead-acid car batteries, to a centrally located energy supply such as a
micro-hydro scheme.
Battery charging can be done during the periods when the power system is not being used to
its full capacity thus improving systems load factor.
Technologies for affordable electricity
One aspect to making energy schemes successful is to reduce the cost of the scheme through
the various methods outlined below.
• Sizing the system components to suit demand
• Local manufacture
• Selection of appropriate technology for components
Small-scale manufacturing plays a huge role in the development of any region. Renewable
energy technology can be used to stimulate indigenous manufacturing. The technology has to
be appropriate for the region in question, or adapted to make it suitable. By developing small-
scale manufacturing, renewable energy can be introduced to more users at a lower cost than
sophisticated imports, and equipment can be repaired and maintained more easily. Local
manufacture creates employment and local added-value, improving the general economic
situation.
Once a system is installed it has to be adequately maintained, so a support infrastructure
needs to be established. This may require a training programme and appropriate
documentation, regular refresher training, and an accessible supply of spare parts.
Transmission and distribution lines
Mini distribution systems require careful consideration as they can potentially add a huge
amount of expense to a scheme.
Standard distribution systems based the principles of national grid systems are over
engineered for rural electrification schemes. Consequently, various low cost alternatives have
been used for such schemes.
• Three-phase high voltage
Three or four wire systems can be used for three-phase high voltage systems. Four
wire systems use three phase wires and a neutral return. With the three-wire approach
limits the voltage that can be supplied voltage between phases known as the phase
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