(distributed generation) is defined as installation and operation of small
modular power generating technologies that can be combined with energy
management and storage systems. It is used to improve the operations of the
electricity delivery systems at or near the end user. These systems may or may
not be connected to the electric grid.
distributed generation system can employ a range of technological options from
renewable to non-renewable and can operate either in a connected grid or
off-grid mode. The size of a distributed generation system typically ranges
from less than a kilowatt to a few megawatts.
can be classified either on the basis of the prime movers used?engines,
turbines, fuel cells?or on the basis of fuel resources used?renewable and
non-renewable. In India, many renewable energy technologies are being employed
in a number of distributed generation projects. The technologies include
biomass gasifiers, solar thermal and photovoltaic systems, small wind turbines
(aero-generators), and small hydro-power plants. The figure illustrates the
technology options for distributed power generation.
Relevance of distributed generation
distributed generation has found three distinct markets.
- Back-up small power generation
systems including diesel generators that are being used in the domestic
and small-commercial sectors.
- Stand-alone off-grid systems or
mini-grids for electrification of rural and remote areas.
- Large-captive power plants such
as those installed by power intensive industries.
power generation systems are needed to address the following issues.
- High peak load shortages? With a deficit of 12.3% in peak demand, distributed generation
systems that can reduce the peak demand is seen as the most effective solution
to the problem.
- High transmission and distribution losses? Current losses amount to about 35.03% of the total available
energy. Distributed power generation systems can greatly reduce these losses
and improve the reliability of the grid network.
- Remote and inaccessible areas? In many parts of the country extension of the grid may not
be economically feasible. In such cases distributed generation can play a
- Rural electrification? Rural
electrification has been identified as a priority for rural development by
the Government of India. Wherever grid extension is not feasible, the
government has directed that decentralized distribution generation
facilities with local distribution network be provided.
- Faster response to new power demands? The modular nature of distributed generation system coupled
with low gestation period enables the easy capacity additions when
- Improved supply reliability and power quality ??Disruptions such as grid failure, etc., can be prevented as
electricity is produced close to the consumer. The quality of power? voltage
and frequency?can also be maintained easily.
- Possibility of better energy and load management? Distributed generation systems offer the possibility of
combining energy storage and management systems.
- Optimal use of the existing grid assets? Inadequacies in distribution network has been one of the major
reasons for poor supply of power. Distributed generation facilitates an
optimal use of the grid that improves the reliability of the grid network
and reduces the congestion.
for distributed generation
Integrated Energy Policy of the Planning Commission of the Government of India
envisions energy security for the country and its citizens by stating that
energy services should be safe, reliable, techno-economically viable, and
sustainable considering different forms and fuels of energy?conventional as
well as new, alternate sources.
Electricity Act, 2003 has also given a thrust to distributed generation
particularly in the context of rural electrification. The Act, in addition to
grid extension as a mode for rural electrification, specifies distributed
generation and supply through stand-alone conventional and renewable energy
systems. It also includes the distribution of electricity through NGOs, local
government units, community groups, and franchisees of distribution utility as
alternate modes for rural electrification.
Act indicates that persons setting up new projects and/or extending existing
infrastructure for composite schemes of generation and distribution are exempt
from licensing and licensee related obligations.
National Electricity Policy notified on 12 February 2005 mentions under the
Rural Electrification component, section 5.1.2 (a) that to provide a reliable
rural electrification system, a Rural Electrification Distribution Backbone be
established by extending the transmission lines. However, when the extension is
not feasible, as in section 5.1.2 (d), it directs that decentralized
distributed generation facilities (using conventional or non-conventional
sources of energy) together with local distribution network be provided.
compliance with sections 4 and 5 of the Electricity Act 2003, the central
government prepared the Rural Electrification policy. The policy in section 3
(3.3) identifies decentralized distributed generation of electricity by setting
up of facilities together with local distribution network based on either
conventional or non-conventional resources methods of generation.
specific schemes of the Government of India, the RGGVY (Rajiv Gandhi Grameen
Vidyutikaran Yojna) and the RVE (Remote Village Electrification) scheme,
provide upto 90% capital subsidy for rural electrification projects using DDG
(decentralized distributed generation) options based on conventional and
non-conventional fuels respectively.?