F UTURE G ENERATING O PTION

What do we mean by Distributed Generation?

Distributed Generation, also called: on-site generation, dispersed generation, embedded generation, decentralized generation, decentralized energy, or distributed energy generates electricity from many small energy sources. Distributed Generation, also called: on-site generation, dispersed generation, embedded generation, decentralized generation, decentralized energy, or distributed energy generates electricity from many small energy sources.

W HY D O W E N EED I T Distributed Generation is mostly needed due to: Efficient generation of power. Economization of the process involved in power generation. To make the process an Environment friendly one. Distributed Generation is mostly needed due to: Efficient generation of power. Economization of the process involved in power generation. To make the process an Environment friendly one.

A L OCALIZED G ENERATION  Distributed generation minimizes energy loss since the process involved production of power at just nearby to the purpose of its use. Moreover, it reduces amount of power transmission lines as well.  Typical distributed power sources in a Feed-in Tariff (FIT) scheme have low maintenance, low pollution and high efficiencies.  In the past, these traits required measures to reduce pollution. However, modern systems can provide these traits with automated operation and renewable, which could in turn reduce size of power plant.  Distributed generation minimizes energy loss since the process involved production of power at just nearby to the purpose of its use. Moreover, it reduces amount of power transmission lines as well.  Typical distributed power sources in a Feed-in Tariff (FIT) scheme have low maintenance, low pollution and high efficiencies.  In the past, these traits required measures to reduce pollution. However, modern systems can provide these traits with automated operation and renewable, which could in turn reduce size of power plant.

D ISTRIBUTED E NERGY R ESOURCES Distributed energy resource (DER) systems are small-scale power generation technologies (typically in the range of 3 kW to 10,000 kW), used to provide an alternative to or an enhancement of the traditional electric power system. The usual problem with distributed generators are their high costs. Distributed energy resource (DER) systems are small-scale power generation technologies (typically in the range of 3 kW to 10,000 kW), used to provide an alternative to or an enhancement of the traditional electric power system. The usual problem with distributed generators are their high costs.

S OLAR P ANELS One popular source of distributed generation is solar panels. But they are costly. Some solar cells also have waste disposal issues, since "thin-film" type solar cells often contain heavy-metal electronic wastes that need to be recycled. The advantages include absence of fuel costs, pollution, mining safety or operating safety issues. Solar also has a low duty cycle, producing peak power at local noon each day. Average duty cycle is typically 20%. One popular source of distributed generation is solar panels. But they are costly. Some solar cells also have waste disposal issues, since "thin-film" type solar cells often contain heavy-metal electronic wastes that need to be recycled. The advantages include absence of fuel costs, pollution, mining safety or operating safety issues. Solar also has a low duty cycle, producing peak power at local noon each day. Average duty cycle is typically 20%.

W IND T URBINES Another distributed generation source is small wind turbines. These have low maintenance, and low pollution. However, wind towers and generators have substantial insurable liabilities caused by high winds, but good operating safety. Wind also tends to be complementary to solar; on days there is no sun there tends to be wind. Another distributed generation source is small wind turbines. These have low maintenance, and low pollution. However, wind towers and generators have substantial insurable liabilities caused by high winds, but good operating safety. Wind also tends to be complementary to solar; on days there is no sun there tends to be wind.

O THER S OURCES Solid oxide fuel cells using natural gas have recently become a distributed energy resource. In countries with high pressure gas distribution, small turbines can be used to bring the gas pressure to domestic levels whilst extracting useful energy. Future generations of electric vehicles will have the ability to deliver power from the battery into the grid when needed. An electric vehicle network could also be an important distributed generation resource. Solid oxide fuel cells using natural gas have recently become a distributed energy resource. In countries with high pressure gas distribution, small turbines can be used to bring the gas pressure to domestic levels whilst extracting useful energy. Future generations of electric vehicles will have the ability to deliver power from the battery into the grid when needed. An electric vehicle network could also be an important distributed generation resource.

C O- G ENERATORS  Co-generators are pretty costly as compared to central generators. However co-generation can extract more value from the fuel.  Distributed cogeneration sources use natural gas-fired micro turbines or reciprocating engines to turn generators. The hot exhaust is then used for space or water heating, or to drive an absorptive chiller for air-conditioning.  Some larger installations utilize combined cycle generation. Usually this consists of a gas turbine whose exhaust gases boils water for a steam turbine in a Rankine cycle. The condenser of the steam cycle provides the heat for space heating or an absorptive chiller. Combined cycle plants with cogeneration have the highest known thermal efficiencies, often exceeding 85%.  Co-generators are pretty costly as compared to central generators. However co-generation can extract more value from the fuel.  Distributed cogeneration sources use natural gas-fired micro turbines or reciprocating engines to turn generators. The hot exhaust is then used for space or water heating, or to drive an absorptive chiller for air-conditioning.  Some larger installations utilize combined cycle generation. Usually this consists of a gas turbine whose exhaust gases boils water for a steam turbine in a Rankine cycle. The condenser of the steam cycle provides the heat for space heating or an absorptive chiller. Combined cycle plants with cogeneration have the highest known thermal efficiencies, often exceeding 85%.

M ICRO- G RID A micro-grid is a localized grouping of electricity generation, energy storage, and loads that normally operates connected to a traditional centralized grid (macro-grid). Micro-grid can be made to function autonomously by disconnecting it from the macro-grid. Generation and loads in a microgrid are usually interconnected at low voltage. Micro-grid generation resources can include fuel cells, wind, solar, or other energy sources. The multiple dispersed generation sources and ability to isolate the microgrid from a larger network would provide highly reliable electric power. Byproduct heat from generation sources could be used for local process heating or space heating. A micro-grid is a localized grouping of electricity generation, energy storage, and loads that normally operates connected to a traditional centralized grid (macro-grid). Micro-grid can be made to function autonomously by disconnecting it from the macro-grid. Generation and loads in a microgrid are usually interconnected at low voltage. Micro-grid generation resources can include fuel cells, wind, solar, or other energy sources. The multiple dispersed generation sources and ability to isolate the microgrid from a larger network would provide highly reliable electric power. Byproduct heat from generation sources could be used for local process heating or space heating.

D ISTRIBUTION G RID W ITH A H IGH P ENETRATION O F DG T ECHNOLOGY

M ODES O F P OWER G ENERATION DER systems may include the following devices/technologies:  Combined heat power (CHP).  Fuel cells.  Micro combined heat and power (Micro-CHP).  Micro-turbines.  Photovoltaic Systems.  Reciprocating engines.  Small Wind power systems.  Stirling engines. DER systems may include the following devices/technologies:  Combined heat power (CHP).  Fuel cells.  Micro combined heat and power (Micro-CHP).  Micro-turbines.  Photovoltaic Systems.  Reciprocating engines.  Small Wind power systems.  Stirling engines.

P OWER G ENERATION O PTION ( A F UTURE V IEW) Conventional Power Generation Distributed Power Generation

C ONCLUSION In general, it is difficult to say what the limit to implementation of DG technology in distribution grids is. Different parameters need to be accounted for, which include: voltage stability, power quality, safety issues and reliability of supply. These in turn depend on many different characteristics of loads, grid topology and supporting transmission grid backbone. Some even pose the question whether it is necessary to keep the current standards of reliability and quality of supply. In practice, one tries to keep up the reliability of the supply, which is a conservative attitude, but understandable in the situation in which a society heavily depends on a reliable power supply. In order to determine the adequate level of DG implementation, in- depth studies of the grid impact, considering static voltage profiles, power quality and dynamic behaviour, including guaranteeing safety in case of faults, need to be made. In general, it is difficult to say what the limit to implementation of DG technology in distribution grids is. Different parameters need to be accounted for, which include: voltage stability, power quality, safety issues and reliability of supply. These in turn depend on many different characteristics of loads, grid topology and supporting transmission grid backbone. Some even pose the question whether it is necessary to keep the current standards of reliability and quality of supply. In practice, one tries to keep up the reliability of the supply, which is a conservative attitude, but understandable in the situation in which a society heavily depends on a reliable power supply. In order to determine the adequate level of DG implementation, in- depth studies of the grid impact, considering static voltage profiles, power quality and dynamic behaviour, including guaranteeing safety in case of faults, need to be made.