page 1
page 2
page 3
page 4
page 5
page 6 page 7
page 8
< prev - next > Energy Grid connection (Printable PDF)
Grid connection
Practical Action
Low cost grid connection
Where grid connection is an option, be it to the national grid or a micro-grid, then one method of
making it an affordable option is to keep the connection costs and subsequent bills to a
minimum. Often, rural domestic consumers will require only a small quantity of power to light
their houses and run a radio or television. There are a number of solutions that can specifically
help low-income households to obtain an electricity connection and help utilities meet their
required return on investment. These include:
Load limited supply. Load limiters work by limiting the current supplied to the consumer
to a prescribed value. If the current exceeds that value then the device automatically
disconnects the power supply. The consumer is charged a fixed monthly fee irrespective
of the total amount of energy consumed. The device is simple and cheap and does away
with the need for an expensive metre and subsequent meter reading.
Reduced service connection costs. Limiting load supply can also help reduce costs on
cable, as the maximum power drawn is low and so smaller cable sizes can be used. Also
alternative cable poles can sometimes be found to help reduce costs.
Pre-fabricated wiring systems. Wiring looms can be manufactured ‘ready to install’
which will not only reduce costs but also guarantee safety standards.
Credit. Credit schemes can allow householders to overcome the barrier imposed by the
initial entry costs of grid connection. Once connected, energy savings on other fuels can
enable repayments to be made. Using electricity for lighting, for example, is a fraction
of the cost of using kerosene.
Community involvement. Formation of community committees and co-operatives who
are pro-active in all stages of the electrification process can help reduce costs as well as
provide a better service. For example, community revenue collection can help reduce the
cost of collection for the utility and hence the consumer.
Electricity Cooperatives Nepal
Nepal has adopted a new strategy whereby it intends to sell power in bulk to rural electricity
consumer groups after putting up the distribution infrastructure. Under this program,
consumer associations typically in the form of cooperatives will take the responsibility of
managing, maintaining, and expanding the rural distribution of electricity. Communities raise
20% of the investment cost for grid extension to their area and 80% of the funds is provided
by the Nepali government. It is expected that this will reduce costs of distribution and also
pilferage of electricity. A number of applications from rural communities have been approved
for implementation.
Low Cost Distribution networks
There are a number of options for reducing the over all cost of a distribution system for rural
electrification. Each option must be considered for the local conditions (distance to be covered
by distribution lines, how disperse are the customers, predicted electrical loads). Some options
which have been used in a number of countries include:
Careful balance between use of high voltage transmission lines and low voltage
distributions lines. Lower voltage lines are lower cost to install, but incur higher losses of
power. (See Tunisia example in box below)
Low cost distribution poles: one cost-effective way to install overhead distribution poles
in off-road locations is to use steel distribution poles (where available) as an alternative
to wood poles. Alternatively locally available wood poles can be used.
Single wire earth return (SWER) or single wire ground return is a single-wire
transmission line for supplying single-phase electrical power to remote areas at low cost.
It is often used in sparsely populated areas where the cost of building an isolated
distribution line cannot be justified. Capital costs are roughly 50% of an equivalent two-
wire single-phase line. Maintenance costs are roughly 50% of an equivalent line. This
has been widely used in Australian, but has also been applied in parts of Brazil and
6