**2. Technologies of distributed energy and their structure**

Distributed energy technologies (distributed energy resources, DER) in the world practice [1] include a wide range of technologies:


The basic characteristic of all these technologies is proximity to the energy consumer. Distributed generation is a set of power plants located close to the place of energy consumption and is connected either directly to the consumer or to the distribution electrical network (in the case when there are several consumers). The type of primary energy source used by the station (e.g., fossil fuel or renewable energy), as well as the station's relevance to consumer, generating or grid-supplying company, or a third party, does not matter. In foreign practice there is a tendency to limit the power of distributed generation power plants by the top bar, depending on the technology used. For example, Navigant Research uses a 500 kW boundary for wind, 1 MW for solar, 250 kW for gas turbines, and 6 MW for gas piston and diesel power plants. The European Distributed Energy Partnership Project (EU-DEEP) used similar boundaries: thermal power plants (steam, gas turbines, piston engines) up to 10 MW, microturbines up to 500 kW, wind power stations up to 6 MW, and solar up to 5 MW.

In Russia, there is no consensus on this issue, and there are no restrictions in regulatory documents. On the other hand, the 25 MW total for all technologies is sometimes used (which "separates" the power plants from the retail and wholesale electricity and capacity markets). Some experts insist that distributed generation cannot have power limitations—in this logic, distributed power generation should

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4 years ahead).

lators (vehicle-to-grid technology).

exception to this practice.

*Dissemination of Distributed Energy Technologies DOI: http://dx.doi.org/10.5772/intechopen.88604*

towns (the capacity of some of them exceeds 1000 MW).

voltage level of network connection, and many others.

ply zones and isolated power systems are not the focus of this study.

the system's requirements for the given capacity of power plants.

object in parallel with an existing electrical network or in island mode.

include all power plants owned by consumers, including large industrial combined heat and power plants (CHP) with a capacity of more than 200 MW (located near large factories and plants). There is no consensus about the distributed generation of heating CHP plants with a capacity of more than 25 MW located in cities and

Among the criteria for the classification of distributed generation types, they also distinguish the type of fuel (from gas to secondary energy resources, for example, blast furnace gas, associated petroleum, and coke oven gas), generation technology (from steam power plants to wind generators), location, the amount of energy consumption by the main ("anchor") consumer (stations), mode factor,

In this study, we see distributed generation including power plants located close to the consumer, connected to a distribution grid (110 kV and below) or directly supplying electricity to the consumer. The limitation on power and technology is not taken into account (if this is not specified separately). Autonomous power sup-

Demand management is the change in energy consumption and power consumption by final users relative to their normal load profile due to changes in electricity prices needed to reduce system-wide costs in exchange for incentive payments from the energy market. For this study, it is important that demand management reduces the magnitude of peak loads in the power system and, accordingly, the system's need for installed capacity of power plants in the short term (day, week), medium term (1 year), and long term (e.g., during long-term power take

Energy efficiency and energy saving in this study are considered as a set of actions on the side of electricity consumer and lead to a long-term decrease in its energy demand. The focus of the study is on energy-saving measures that reduce the need for energy at times of power system peak loads and, accordingly, reduce

Microgrid is an integrated power system consisting of distributed energy resources and several electrical loads (consumers), operating as a sole managed

Distributed power storage systems (accumulators) are a set of storage systems installed at ultimate customer's side and at distribution network facilities and providing, among other things, backup and demand management capabilities.

Electric cars are considered as one of the types of distributed energy resources, since they play a role not only to energy consumers but also to distributed accumu-

The power systems of Russia and foreign countries starting from the second half of the twentieth century historically developed in a similar logic. Large power plants were usually built near fuel extraction sites (in Russia, peat and coal, later—gas and fuel oil) or close to transport corridors along which this fuel was transported, as well as near large bodies of water or rivers. The more powerful was a power plant (scale effect), the cheaper was its construction (per 1 kW of power)—therefore, the average unit capacity of the stations grew steadily, increasing 500 times and more from the 1920s to the 1980s. The stations were often located at a considerable distance from large cities, for environmental reasons. In Russia, combined heat and power plants (CHP), built in close proximity to the consumer of thermal energy (city, plant, etc.) and electrical energy (industrial CHP), became an

The transmission of electrical energy from the stations to consumers was carried

out through the construction of trunk lines (voltage 220–500 kV and above to reduce transmission losses) and through the distribution electrical networks with

#### *Dissemination of Distributed Energy Technologies DOI: http://dx.doi.org/10.5772/intechopen.88604*

*Intellectual Property Rights - Patent*

new technologies by industrial companies in Russia. For the analysis of the most significant factors of distributed power generation technology adoption, industrial companies conducted in-depth semi-structured interviews with representatives of large industrial companies (8 companies) and a survey of industrial companies (69 companies). A regression model was used for the analysis, which allows determining the strength and significance of the influence of selected factors on the compa-

The results obtained allow us to conclude that for analyzed companies, technical feasibility, the cost of electricity, and perceived benefits are critical factors in deciding on the use of distributed power generation technologies. The risk factor turned out to be insignificant, which the companies explained in the in-depth interviews by the fact that distributed power generation systems reduce the occurrence of the listed adverse effects to a minimum. Obtaining cheap electric and thermal energy, a gradual increase in energy capacities and evenness of investment with fast energy generation for industrial and household needs are possible today due to the use of energy-efficient solutions based on distributed power generation technologies.

nies' decision-making on their own power generation.

**2. Technologies of distributed energy and their structure**

world practice [1] include a wide range of technologies:

• Demand management (demand response)

• Distributed generation

• Microgrids

• Electric cars

• Energy efficiency management

• Distributed power storage systems

Distributed energy technologies (distributed energy resources, DER) in the

The basic characteristic of all these technologies is proximity to the energy consumer. Distributed generation is a set of power plants located close to the place of energy consumption and is connected either directly to the consumer or to the distribution electrical network (in the case when there are several consumers). The type of primary energy source used by the station (e.g., fossil fuel or renewable energy), as well as the station's relevance to consumer, generating or grid-supplying company, or a third party, does not matter. In foreign practice there is a tendency to limit the power of distributed generation power plants by the top bar, depending on the technology used. For example, Navigant Research uses a 500 kW boundary for wind, 1 MW for solar, 250 kW for gas turbines, and 6 MW for gas piston and diesel power plants. The European Distributed Energy Partnership Project (EU-DEEP) used similar boundaries: thermal power plants (steam, gas turbines, piston engines) up to 10 MW, microturbines up to 500 kW, wind power stations up to 6 MW, and solar up to 5 MW. In Russia, there is no consensus on this issue, and there are no restrictions in regulatory documents. On the other hand, the 25 MW total for all technologies is sometimes used (which "separates" the power plants from the retail and wholesale electricity and capacity markets). Some experts insist that distributed generation cannot have power limitations—in this logic, distributed power generation should

**144**

include all power plants owned by consumers, including large industrial combined heat and power plants (CHP) with a capacity of more than 200 MW (located near large factories and plants). There is no consensus about the distributed generation of heating CHP plants with a capacity of more than 25 MW located in cities and towns (the capacity of some of them exceeds 1000 MW).

Among the criteria for the classification of distributed generation types, they also distinguish the type of fuel (from gas to secondary energy resources, for example, blast furnace gas, associated petroleum, and coke oven gas), generation technology (from steam power plants to wind generators), location, the amount of energy consumption by the main ("anchor") consumer (stations), mode factor, voltage level of network connection, and many others.

In this study, we see distributed generation including power plants located close to the consumer, connected to a distribution grid (110 kV and below) or directly supplying electricity to the consumer. The limitation on power and technology is not taken into account (if this is not specified separately). Autonomous power supply zones and isolated power systems are not the focus of this study.

Demand management is the change in energy consumption and power consumption by final users relative to their normal load profile due to changes in electricity prices needed to reduce system-wide costs in exchange for incentive payments from the energy market. For this study, it is important that demand management reduces the magnitude of peak loads in the power system and, accordingly, the system's need for installed capacity of power plants in the short term (day, week), medium term (1 year), and long term (e.g., during long-term power take 4 years ahead).

Energy efficiency and energy saving in this study are considered as a set of actions on the side of electricity consumer and lead to a long-term decrease in its energy demand. The focus of the study is on energy-saving measures that reduce the need for energy at times of power system peak loads and, accordingly, reduce the system's requirements for the given capacity of power plants.

Microgrid is an integrated power system consisting of distributed energy resources and several electrical loads (consumers), operating as a sole managed object in parallel with an existing electrical network or in island mode.

Distributed power storage systems (accumulators) are a set of storage systems installed at ultimate customer's side and at distribution network facilities and providing, among other things, backup and demand management capabilities.

Electric cars are considered as one of the types of distributed energy resources, since they play a role not only to energy consumers but also to distributed accumulators (vehicle-to-grid technology).

The power systems of Russia and foreign countries starting from the second half of the twentieth century historically developed in a similar logic. Large power plants were usually built near fuel extraction sites (in Russia, peat and coal, later—gas and fuel oil) or close to transport corridors along which this fuel was transported, as well as near large bodies of water or rivers. The more powerful was a power plant (scale effect), the cheaper was its construction (per 1 kW of power)—therefore, the average unit capacity of the stations grew steadily, increasing 500 times and more from the 1920s to the 1980s. The stations were often located at a considerable distance from large cities, for environmental reasons. In Russia, combined heat and power plants (CHP), built in close proximity to the consumer of thermal energy (city, plant, etc.) and electrical energy (industrial CHP), became an exception to this practice.

The transmission of electrical energy from the stations to consumers was carried out through the construction of trunk lines (voltage 220–500 kV and above to reduce transmission losses) and through the distribution electrical networks with

a total length of hundreds of thousands of kilometers. At the same time, at the level of medium- and low-voltage distribution networks (35 kV and below), the consumer, as a rule, was at the end of the chain and, unlike larger consumers of supergrids, did not always have a backup power source from the power grid.

For several decades, this power system architecture has remained generally unchanged. Centralized power systems successfully, reliably, and at a reasonable price provided consumers with electricity. But by the end of the twentieth century, the scale effect stopped working; it had been working back in the 1950s, and the oil crisis of the 1970s sharply increased the interest of energy-importing countries in new energy-efficient power generation technologies.

The catalyst for change was distributed generation, namely, the emergence of new electricity production technologies in the 1970s and 1980s in the USA and Europe—gas turbine, gas piston, and combined cycle—that allowed creating lowcost and efficient power plants of small capacity from tens of kW to tens of MW (**Figure 1**).

This immediately led to an increase in distributed generation usage (**Figure 2**).

In addition to distributed generation, new opportunities for energy-saving technologies and demand management have opened up in the electric power industry. A classic example is the "Energy Demand Management" program, launched in the 1970s in the USA, aimed at saving electricity by encouraging consumers to reduce energy consumption during peak periods of demand or to shift energy consumption to off-peak demand periods.

In the first decade of the twenty-first century, the rapid development of renewable energy sources began. Governments in Europe, the USA, and other countries, striving for carbon-free energy and reducing dependence on energy exports, adopted large-scale and long-term programs to support renewable energy, after which the cost of solar and wind energy systems dropped several times with a significant increase in their technological efficiency. Thus, the present value of electricity from solar and wind power plants in 2009–2017 decreased by 67–86% (**Figure 3**).

As a result, in just 20–30 years, a consumer from a situation of deterministic centralized energy power supply came to choose from a wide range of alternative solutions that allow using them in an optimal proportion, based on individual priorities of cost, reliability, and quality of power supply.

The experience of the Northern European countries shows that it is better to develop distributed generation in conjunction with distributed heat supply, using cogeneration—the technology of co-production of heat and electricity in a single

#### **Figure 1.**

*Illustration of the scale effect (and its exhaustion) in the cost of the gas power plant construction in 1930–1990 depending on their power (MW). Source: Hunt et al. [2].*

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**Figure 2.**

**Figure 3.**

*Dissemination of Distributed Energy Technologies DOI: http://dx.doi.org/10.5772/intechopen.88604*

cycle. Distributed cogeneration in these countries has become the first step toward effective decentralization of power systems and, among other things, has reduced the cost of maintaining the supergrids and eliminating irrational energy losses. For example, in Denmark, the system of supporting measures for mini-CHP led to the emergence of hundreds of small natural gas and biomass energy centers in only 10–20 years. In addition, the number of wind power plants has increased.

*Dynamics of levelized cost of electricity (LCOE) from solar and wind power plants in 2009–2017, USD/MWh.* 

*Dynamics of distributed generation development in the USA (GW). Source: Rhodium Group [3].*

According to the Danish Energy Agency, the development of distributed cogeneration reduced the annual consumption of primary energy in Denmark by 11% and

The appearance of many new small generators has complicated the processes of their integration into the unified power grid and management and regulation processes. That situation demanded new technologies of flexible network construction and intelligent control of them, which later became known as the smart

reduced CO2 emissions by 4.5 million tons per year.

*Source: Lazard's Levelized Cost of Energy Analysis, version 11.0 [4].*

#### *Dissemination of Distributed Energy Technologies DOI: http://dx.doi.org/10.5772/intechopen.88604*

#### **Figure 2.**

*Intellectual Property Rights - Patent*

(**Figure 1**).

(**Figure 3**).

tion to off-peak demand periods.

a total length of hundreds of thousands of kilometers. At the same time, at the level of medium- and low-voltage distribution networks (35 kV and below), the consumer, as a rule, was at the end of the chain and, unlike larger consumers of supergrids, did not always have a backup power source from the power grid. For several decades, this power system architecture has remained generally unchanged. Centralized power systems successfully, reliably, and at a reasonable price provided consumers with electricity. But by the end of the twentieth century, the scale effect stopped working; it had been working back in the 1950s, and the oil crisis of the 1970s sharply increased the interest of energy-importing countries in

The catalyst for change was distributed generation, namely, the emergence of new electricity production technologies in the 1970s and 1980s in the USA and Europe—gas turbine, gas piston, and combined cycle—that allowed creating lowcost and efficient power plants of small capacity from tens of kW to tens of MW

This immediately led to an increase in distributed generation usage (**Figure 2**). In addition to distributed generation, new opportunities for energy-saving technologies and demand management have opened up in the electric power industry. A classic example is the "Energy Demand Management" program, launched in the 1970s in the USA, aimed at saving electricity by encouraging consumers to reduce energy consumption during peak periods of demand or to shift energy consump-

In the first decade of the twenty-first century, the rapid development of renewable energy sources began. Governments in Europe, the USA, and other countries, striving for carbon-free energy and reducing dependence on energy exports, adopted large-scale and long-term programs to support renewable energy, after which the cost of solar and wind energy systems dropped several times with a significant increase in their technological efficiency. Thus, the present value of electricity from solar and wind power plants in 2009–2017 decreased by 67–86%

As a result, in just 20–30 years, a consumer from a situation of deterministic centralized energy power supply came to choose from a wide range of alternative solutions that allow using them in an optimal proportion, based on individual

The experience of the Northern European countries shows that it is better to develop distributed generation in conjunction with distributed heat supply, using cogeneration—the technology of co-production of heat and electricity in a single

*Illustration of the scale effect (and its exhaustion) in the cost of the gas power plant construction in 1930–1990* 

priorities of cost, reliability, and quality of power supply.

*depending on their power (MW). Source: Hunt et al. [2].*

new energy-efficient power generation technologies.

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**Figure 1.**

*Dynamics of distributed generation development in the USA (GW). Source: Rhodium Group [3].*

#### **Figure 3.**

*Dynamics of levelized cost of electricity (LCOE) from solar and wind power plants in 2009–2017, USD/MWh. Source: Lazard's Levelized Cost of Energy Analysis, version 11.0 [4].*

cycle. Distributed cogeneration in these countries has become the first step toward effective decentralization of power systems and, among other things, has reduced the cost of maintaining the supergrids and eliminating irrational energy losses. For example, in Denmark, the system of supporting measures for mini-CHP led to the emergence of hundreds of small natural gas and biomass energy centers in only 10–20 years. In addition, the number of wind power plants has increased.

According to the Danish Energy Agency, the development of distributed cogeneration reduced the annual consumption of primary energy in Denmark by 11% and reduced CO2 emissions by 4.5 million tons per year.

The appearance of many new small generators has complicated the processes of their integration into the unified power grid and management and regulation processes. That situation demanded new technologies of flexible network construction and intelligent control of them, which later became known as the smart grid. The consumer of electricity begins to play an increasing role in the energy system, mastering new roles—generator and accumulator of electricity. Freedom of consumer choice is increasing. At the same time, there are many opportunities for demand management and energy efficiency both at the level of a specific household and at the level of the economy as a whole.

In order to carry into effect these possibilities, the states are changing the models of electricity and capacity markets toward their liberalization. It can be said without exaggeration that a necessary basis is being formed for building a competitive environment at the retail level with the development of distributed energy.

The entry of distributed energy into the Russian energy system became noticeable in the 2000s, but over the past 17 years, in fact, it was limited to only distributed generation. The development of this process in Russia takes place at a much lower rate, which requires a deep study of the spreading factors of distributed energy technologies.
