“Childhood Diseases” of Small Scale Power Generation

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The MAIN JOURNAL for POWER GRID SPECIALISTS in RUSSIA


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56

August 25–29, France, Paris

“Childhood Diseases” of 

SmallScale Power Generation

Construction of small-scale generation facilities with their connection to public 
distribution grids has recently become a world-wide trend, which is actively promoted 
by government programs on “green energy” development. However, with all advantages 
of renewable energy sources, their connection to the energy system in long term aspect 
still arouses many questions. For instance, lately in the energy community one can 
frequently hear experts airing concerns about the fact that wider integration of small-
scale and distributed generation facilities creates dif

fi

 culties in controlling energy system 

operation and ensuring system reliability, as, comparing to conventional generation, 
such energy facilities are much less sustainable.

Maria RODIONOVA (

Мария

 

РОДИОНОВА

)

S

mall-scale and distributed power generation 
issues were raised during a round-table discussion 
between JSC “System Operator of Uni

fi

 ed 

Energy System” (JSC “SO UES”) and Russian 

National Committee of CIGRE (RNC CIGRE) that took 
place in Moscow. The event was attended by Russian 
and foreign specialists, experts and scienti

fi

 c community 

representatives. The main topic of the discussion was 
integration of small-scale and distributed generation in the 
electric energy system.

CHARACTERISTIC FEATURES

Andrey Pazderin, Doc. of Tech. Sc., Head of the 

Department “Automated Electrical Systems”, Ural Power 
Engineering Institute of Ural Federal University, spoke on 

the characteristics lying in the basis of classifying a power 
generation facility as “small-scale”. According to him, to 
be classi

fi

 ed as a small-scale generation facility, it should 

be located in close proximity to the place of electric 
(thermal) power consumption and have installed capacity 
of not more than 25 MW. In accordance with Russian 
energy legislation and established practices, such facilities 
do not participate in electric power wholesale market 
operation and, as a rule, are owned not by a wholesale 
generation company or a territorial generation company, 
but by consumers or small independent generation 
companies.

In most countries of the world the term “small-scale 

generation” is not widely used, in distinction to the term 
“distributed generation”. In accordance with CIGRE 

criteria, distributed generation is 
generation connected to a distribution 
grid at medium (up to 30 kV) and low 
(less than 1 kV) voltages. In practice, 
distributed generation facilities are 
those with small installed capacity, 
including facilities that use renewable 
energy resources: internal combustion 
installations, wind generation facilities, 
photovoltaic installations (solar panels), 
biomass power stations, micro-turbines, 
energy accumulators and other power 
facilities. However, such facilities, in 
case they are connected to a HV grid 
(over 69 kV), cannot be called distri-
buted generation. For this reason, for 
example, large-scale wind farms and 

Integration of Renewable


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57

info@eepr.ru,   www.eepr.ru

Source: Branan

Denmark

Canada

World

China

USA

Russia

Brazil

52,3

13,5

12,5

11,1

8,1

5,7

3,7

Hydro power plants

Wind energy

Bio thermal power plants

Solar photovoltaics

Geo thermal power plants

CSP

Ocean power plants

970

238

72

70

0,5

1,8

11,2

solar panel 

fi

 elds, according to CIGRE 

criteria, do not belong to distributed 
generation. Also, the professional 
community widely implements the 
term “small-scale power generation”, 
which has caught on as regards small-
scale generation facilities operating 
according to the principle of cogeneration 
(electricity and heat generation) and 
trigeneration (power, heat and cooling), 
which increases the ef

fi

 ciency coef

fi

 cient 

of such installations to 80% and above.

PRACTICES ABROAD

Small-scale generation growth rates in 

foreign countries are high. Yury Kucherov, 
Doc. of Tech. Sc., Head of Department of 
Technical Regulation of JSC “SO UES”, 
member of Technical Committee of RNC 
CIGRE, mentioned, among general world 
trends, the growth of total installed capacity 
of small-scale and distributed generation 
facilities in energy systems of developed 
countries, an increase of installed capacity 
of single facilities of wind power stations, 
development of large-scale wind farms 
and solar power stations. The leader in 
this 

fi

 eld is Germany, which has taken the 

decision to abandon atomic power stations, 
where now the total installed capacity of 
operating photovoltaic installations makes 
up as much as 33 GW, while that of wind 
installations — 32 GW. In Japan the total 
installed capacity of small-scale and 
distributed generation amounts to about 
36 GW, while in Italy — 20 GW. In the 
USA there has been a signi

fi

 cant growth 

since 2010, and small-scale generation has 
increased from 2 to 12 GW.

Yury Kucherov provided an illustrative 

example of Denmark, where the share of 
small-scale and distributed generation in 
the volume of electric power generation 
exceeds 50%. By 2020 Denmark plans to 
supply 33% of its demand by means of 
renewable energy sources, and by 2050 
to completely opt out of generation based 
on the use of organic fuel. At present, 
nine large-scale wind farms with the 
total capacity of about 3.5 GW and more 
than four thousand wind installations, 
the capacity of which exceeds 2.2 GW, 
operate in the country (Fig. 1).

Programs of renewable energy 

development have been developed and 
approved of in more than a hundred 
countries of the world (Fig. 2). The 

need in development of renewables is justi

fi

 ed by such factors as power 

consumption growth, limited character and irregularity of location of world 
reserves of fossil organic energy resources, need in reducing dependence 
on import of energy resources, constant growth of prices for energy 
resources, electric power and heat. In many countries emphasis is made 
on development of wind and solar generation due to relatively greater 
availability of these resources, though such facilities as, for example, hydro 
and geothermal power stations, have a signi

fi

 cantly higher coef

fi

 cient of 

installed capacity use than wind installations and solar panels.

Analysts’ quantitative forecasts vary, but analysts are sure that, in case 

of continuous development of renewables at the same high rates as we 

Fig. 1. Share of distributed generation in the total electric 

power generation volume in the world, 2011, %

Source: Branan

Fig. 2. Renewable energy installed capacities in the 

world, 2011, GW


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58

August 25–29, France, Paris

Yury Kucherov 

Yury Kucherov 

(

Юрий

 

Кучеров

)

(

Юрий

 

Кучеров

)

Source: Main directions of state policy in the sphere

 of improving energy ef

fi

 ciency of power industry based on 

renewable sources of energy for the period up to 2020

BioTPP

Small-scale

 HPP

GeoTPP

Wind farms

Tide power 

plants

Solar power 

plants

1400

1870

750

1567

85

2

0

2010

15

311

14

13

0

500

1000

1500

2000

2020

1817

have now, by the second half of XXI century renewable 
energy will occupy signi

fi

 cant positions in the energy 

balance. According to IEC, the ratio of various sources 
in electric power generation in the world by 2050 will be 
the following: coal and gas — 25% each; atomic energy 
— 18%; hydro energy — 15%, other renewables — 15%. 
According to the European Renewable Energy Council, 
by 2040 the share of renewables in EU will exceed 47% 
of electric power generation; Shell Corporation analysts 
assume that by 2060 the indicator in Europe will stay 
within 60—70%.

Yury Kucherov spoke 

to participants of the event 
about the new 

fi

 eld  of 

implementation of small-
scale and distributed 
generation which has 
formed abroad — 
Smart City projects. 
Implementation of such 
projects is directed at 
ensuring people’s high 
level of life through 
innovative technologies in 
construction, infrastructure 
and everyday life. 
This suggests using 
such technologies as 

smart waste utilization, smart energy saving, smart 
transportation, etc. Within the framework of such projects 
new-type generation complexes are built, which combine 
distributed generation sources of various capacities and 
types, as well as electric and thermal power accumulators 
installed in residential and of

fi

 ce buildings, enterprises. 

Dozens of energy, engineering, scienti

fi

 c and educational 

centres participate in creation and improvement of 
operation conditions of such complexes in energy systems. 
Smart City projects are coordinated by public authorities. 
The world has accumulated quite wide experience in 
implementation of such projects, for example, “Medini 
Iskandar Malaysia” (Malaysia), “Cyberjaya” (Malaysia), 
“Songdo” (Korea), “Masdar City” (UAE). In Russia, April 
2013 marked the start of “SMART City Kazan” project, 
within the framework of which it is planned to build a 
new town in 15 km from the centre of Kazan, which is 
to become a business centre of the Republic of Tatarstan.

RUSSIAN REALIA

What concerns small-scale power generation, Russia 

does not stay away from the general world trends, 
though it has its own peculiarities. One of them is that 
our small-scale generation develops mainly not through 
the government’s will but at the consumers’ initiative 
and without government subsidies. Consumers, mostly 
industrial enterprises, consider their own generation 
(including that meeting the criteria of small-scale and 
distributed one) to be an ef

fi

 cient way of reducing costs 

and solving problems related to connection to power 
grids. Another important peculiarity of Russian small-
scale generation is that small-scale generation facilities 
in Russia mainly operate using organic hydrocarbon fuel 
— natural, lique

fi

 ed or oil-associated gas, diesel fuel 

and mazut, while abroad they are created on the basis of 
renewables (Fig. 3). All these Russian peculiarities can be 
explained by a number of factors enumerated by Andrey 
Pazderin.

Firstly, it is a lower, comparing to conventional 

generation, price for electric power, due to reduction of 
its grid component and fuel costs, as often fuel is a by-
product of basic production. For example, In Sverdlovsk 
Region the cost of 1 kW•h, produced with the use of their 
own generation sources, amounts to 1.5—2.5 rubles, with 
6 rubles per 1 kW•h — with the use of external sources.

Secondly, consumers are motivated to create their own 

generation facilities by annual increases of electric power 
cost in the country. According to Rosstat, during the recent 
3 years the average annual growth of tariffs for electric 
power has amounted to 14%, said Andrey Pazderin.

Thirdly, small-scale generation development is given 

impetus by general growth of demand for electric power. 
Demand for electric power across the UES of Russia by 
the end of 2019 is estimated to be at the level of 1151 
billion kW•h, which is 134.5 billion kW•h more than 
the power consumption level of 2012. The increase with 
respect to the level of 2012 is estimated as 13.2%. Such 

Fig. 3. Renewable energy installed capacities in 

Russia, MW

Integration of Renewable


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Andrey Pazderin 

Andrey Pazderin 

(

Андрей

 

Паздерин

)

(

Андрей

 

Паздерин

)

data are speci

fi

 ed in the newest variant of the Pattern and 

program of development of the Uni

fi

 ed Energy System 

of Russia for 2013—2019, approved by the Ministry of 
Energy of Russia in July of 2013.

Another important factor of small-scale generation 

development, according to Andrey Pazderin, is recent 
formation of a respective technological basis — simple, 
rather reliable, ef

fi

 

cient, ecological and relatively 

inexpensive facilities for electric and thermal power 
generation in volumes required by certain consumers. 
Small-scale and distributed generation development 
is also promoted by strengthening of ecological 
requirements imposed by the state. In particular, such 
an impetus was implementation of 

fi

 nes with respect 

to oil and gas enterprises that burn associated gas in so 
called 

fl

 ares. At present, a signi

fi

 cant share of small-scale 

generation facilities is integrated at oil and gas industry 
enterprises that strive to solve the problem of associated 
gas utilization.

However, on a whole, in UES of Russia renewable 

sources of energy meet only 0.6% demand for electric 
power. Weak development of renewables-based generation 
mainly owes to low investment attractiveness of such 
projects. According to Head of Centre of new power grid 
technologies of JSC “NTC FGC UES”, Doc. of Tech. 
Sc. Nikolay Novikov, there have been no attempts on 
the part of the state to develop an economic mechanism 
for promotion of small-scale generation, in particular, 
renewables, yet. According to him, state subsidies 
and economic incentives for participants of ecological 
generation development projects could be included in 
undertakings aimed at changing the existing situation.

RUSSIAN PROSPECTS

According to Doc. of Tech. Sc., Associate Professor 

of Department “Automated Electrical Systems” of UFU, 
Advisor to Director of JSC “SO UES” Petr Erokhin, 
Russia has a great potential for small-scale generation 
development. There are many under-populated territories, 
isolated from centralized power supply, in our country. 
In these areas small-scale and distributed generation 
development is especially relevant as connection of 
such areas to the Uni

fi

 ed Energy System of Russia in the 

nearest time is not economically feasible. Also, according 
to him, the indication for renewable energy development 
in a number of regions is weather conditions: a large 
number of windy and sunny days a year, availability of 
hydro-resources, etc.

Andrey Pazderin also believes that there are 

natural weather and climatic conditions for renewable 
energy development in Russia. Volgograd, Murmansk, 
Novosibirsk Regions, Krasnodar Krai and Primorsky Krai 
have prospects as regards development of small-scale and 
distributed generation with the use of renewables. For 
example, according to experts’ estimates, renewables-
based generation development in Kuban can provide up to 
1.3 GW of electric power.

Within the framework 

of the subprogram 
“Development of 
renewable sources of 
energy for the period up 
to 2020” of the federal 
program “Modernization 
of electric power industry 
of Russia for the period 
up to 2020” and in 
accordance with plans 
of construction of power 
facilities and power plants 
operating on the basis of 
renewables, investment 
projects providing for 
construction of solar 

panels with installed capacity of about 180 MW on Taman 
Peninsula, as well as coast wind farms in the area of 
Blagoveshchenskaya, Anapa, Gelendzhik and Eysk with 
total capacity of 389 MW are ready to be implemented. A 
wind power plant with total installed capacity of 5.1 MW, 
a generation facility located in the territory of Kaliningrad 
Region, which is unique for Russia, can be used as a good 
reference point during implementation of these projects. 
The wind farm located in the settlement of Kulikovo on 
the coast of the Baltic Sea was commissioned in 2002. The 
project was implemented with support of RAO “UES of 
Russia”, administration of Kaliningrad Region, Ministry 
of Energy of RF and Ministry of Environment and Energy 
of Denmark. The wind power plant, consisting of twenty 
one wind installations, was built with the grant of the 
Danish Government. 

According to Petr 

Erokhin, one of promising 
directions of small-scale 
generation development 
in Russia can be 
cogeneration, which is 
combined generation 
of electric power and 
heat, widely used in 
conventional power 
generation. Modernization 
of existing boiler plants 
up to cogeneration ones 
can increase ef

fi

 ciency 

of power generation 
installations, ensure 

maximum pro

fi

 table electric and thermal power supply of 

consumers and reduce costs of construction of new grids 
in a number of regions of the country.

NEW CHALLENGES

Specialists, experts and scienti

fi

 c  community 

representatives say more frequently that small-scale and 
distributed generation development has a great impact on 

Petr Erokhin 

Petr Erokhin 

(

Пётр

 

Ерохин

)

(

Пётр

 

Ерохин

)


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August 25–29, France, Paris

Integration of Renewable

operation modes of energy systems. In particular, for the 
System operator, who is responsible for supervisory control 
of the Uni

fi

 ed Energy System, small-scale generation 

development forms new conditions of supervision over 
power facilities and new conditions of energy system 
control.

The most important conditions of sustainable 

energy system operation are constant keeping of 
power generation and consumption balance, as well 
as an adequate level of power accumulation in case of 
unpredictable outages of power generation installations 
and grid components. For these conditions to be met, 
a great share of generation facilities should be capable 
of dynamic power output variation (control response), 
should use various kinds of fuel (fuel redundancy), be 
“visible” for dispatch centres (availability of telemetry 
devices), and meet a number of other requirements. 
However, small-scale and distributed generation has 
signi

fi

 cant gaps in the 

fi

 eld.

Small-scale generation facilities do not have the 

required control response that makes it possible to 
dynamically react to changes in operating conditions and 
increase quality of frequency and power 

fl

 ow control in the 

energy system. The economically feasible operation mode 
of a small-scale generation installation is continuous load 
within 85—100% of the rated value; at that, the problem 
of irregularity of daily power consumption patterns is to 
be solved by conventional generators of the centralized 
energy system, which simply cannot provide the power 
balance with the existing high share of small-scale and 
distributed generation because of their limited control 
response capabilities.

Taking into account the fact that in Russia small-scale 

generation facilities mainly use organic fuel, another 
problem of their insuf

fi

 cient reliability caused by no fuel 

redundancy can be added. It means that power facilities 
have no redundant channels of fuel supply and use one 
kind of fuel only.

Besides, electric power generation by renewables-

based generation facilities depends on weather 
conditions, which constantly change. Therefore, such 
generation is unable to provide electric power for a long 
time sustainably and regularly like conventional power 
generators. That is, reliable and sustainable power 
supply of consumers in various climatic situations is not 
provided for.

In addition, at present there is a large number of 

small-scale and distributed generation facilities that are 
“invisible” for system operators, i.e. they are not equipped 
with telemetry systems, enabling their visibility for control 
centres.

With the existing small-scale generation development 

level in Russia, these problems are still not too relevant, 
but a signi

fi

 cant increase of its share means that the 

energy system starts to have low-response generation, 
which does not participate in frequency and power 

fl

 ow control and requires redundancy by conventional 

generation sources. To the meeting participants’ common 
opinion, with a large share of small-scale and distributed 
generation in the total electric power generation in the 
energy system, there can arise dif

fi

 culties with power 

balance provision.

Yury Kucherov stated that abroad problems of 

integrating small-scale generation sources in the energy 
system are solved quite successfully. For example, 
power accumulators, which enable smoothing of climatic 

fl

 uctuations, are used as an integrating link, which makes 

it possible to provide reliable power supply to consumers. 
In addition, new control facilities are formed in the energy 
system, where various small-scale generation facilities 
are combined with the aim of improving monitoring and 
control. For example, these are “virtual” power plants, 
which represent a number of small-scale generation 
facilities in a certain territory as a single object of dispatch 
control; “micro energy systems”, including various energy 
sources, e.g. “smart houses” with their own generation 
sources (wind generators, solar panels, diesel generators); 
and “multi micro energy systems”, which combine several 
micro energy systems.

Yury Kucherov underlined that at the same time solving 

of the small-scale generation problem in energy systems 
abroad now corresponds to the development level of this 
generation, but with further increase in the number of such 
energy facilities there will arise new problems mostly 
connected with the growth of their impact on operation 
modes of energy systems. Taking this into account, in a 
number of countries, for example, in Germany and China, 
regulatory authorities and professional communities 
conduct active work on adjustment of existing technical 
requirements to small-scale and distributed generation 
facilities.

Yury Kucherov drew attention of the round-table 

discussion participants to another important aspect, which 
came into being due to “green energy” development, 
namely economic one. Recently in a number of 
countries there has arisen a con

fl

 ict of interests between 

conventional and distributed generation based on 
renewables. Contradictions are related to state support of 
renewables, which in

fl

 uences redistribution of incomes of 

power generation and grid companies.

TASKS TO BE 

SOLVED IMMEDIATELY

With active development of small-scale and 

distributed generation in conditions when precise 
requirements to its operation within UES of Russia 
have not been established yet there can arise dif

fi

 culties 

in energy system control, Petr Erokhin summarized on 
the results of the round-table discussion. Nevertheless, 
it is not a reason for suspending activities of consumers 
wishing to build their own small-scale generation 
facilities. The task of the System operator, who is 
responsible for sustainable operation of the UES of 
Russia, is to examine every situation, consult future 


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R&D tasks of small-scale 

and distributed generation development 

(based on the 

fi

 nal resolution 

of the round-table discussion):

•   analysis of the world experience in modelling 

and development of one’s own models of 
primary engines of small-scale generation 
(gas-fueled reciprocating, gas turbine, CCGT 
installations) and their control systems;

•   research of behavior of small-scale generation 

facilities in case of disturbances in the external 
grid, analysis of the capability of equipment to 
continue operation in case of such disturbances, 
as well as specifying requirements to control 
systems that improve sustainability of small-
scale generation installations;

•   analysis of impact of small-scale generation on 

static and dynamic energy system sustainability;

•   analysis of ways to implement new technologies 

(power accumulators, semi-conductor devices, 
asynchronized synchronous generators, 
frequency-controlled drive, etc.) for increasing 
small-scale generation sustainability;

• 

 analysis of opportunities of autonomous 

operation of small-scale generation installations 
and establishment of requirements to small-
scale generation control systems to enable such 
operation;

•   analysis, including that of foreign experience, of 

possibilities of controlling autonomous energy 
systems with a large share of renewables-based 
generation — wind and solar energy.

owners of small-scale generation facilities on issues 
that can arise, advise them of the problems which they 
will have to face while implementing their plans, and 
promote development and establishment, on the state 
level, of technical requirements to construction of 
small-scale and distributed generation facilities and 
their operation within the energy system with their 
maximum efforts, he emphasized.

The participants of the meeting stated that information 

provided by various international professional 
organizations, especially CIGRE, which has already 

accumulated a large volume of data on operation of small-
scale generation facilities in the world, as well as of the 
process of standardization of technical requirements to 
distributed generation sources in different countries, can 
be useful in the process of development of regulations and 
technical requirements in Russia.

According to the participants of the round-table 

discussion, a concept and standards specifying 
requirements to small-scale generation for its sustainable 
operation within energy systems should be developed in 
Russia in the nearest time. Andrey Pazderin emphasized 
that this requires mathematical modeling for preliminary 
analysis of the impact of small-scale generation on the 
energy system in normal, emergency and post-emergency 
modes, specifying ways to solve R&D and organizational 
problems of connecting small-scale generation 
installations to power grids and their operation, developing 
standard technical speci

fi

 cations and requirements for 

such installations.

Russia is a country with special conditions: cold 

climate and large distances. Therefore, according to the 
participants of the meeting, a special role in successful 
development of small-scale generation should belong 
to pilot projects implemented in different regions of 
the country with account for local peculiarities, as well 
as Russian characteristics in heat generation sector, in 
particular, availability of a large number of boiler plants, 
which could be used for electric power generation. 
Implementation of pilot projects will enable developing 
required standards and typical “road maps” specifying the 
strategy of development in this 

fi

 eld.

Small-scale generation development also requires 

training of highly quali

fi

 ed personnel for designing and 

operation of small-scale generation facilities. During 
the meeting representatives of the Russian National 
Committee of CIGRE spoke on the need in developing 
research and educational competences in higher 
educational establishments in the 

fi

 eld of small-scale 

generation, while using the mechanism of distribution of 
R&D papers developed by RNC CIGRE in 2013.

A number of tasks the scienti

fi

 c community is to solve 

in connection with small-scale and distributed generation 
development in Russia has been speci

fi

 ed based on the 

results of the meeting. They are related primarily to 
dif

fi

 culties in energy system control connected with small-

scale generation development and inadequate attention 
to problems of operation of small-scale generation 
installations.

Head of C6 “Distribution Systems and Dispersed 

Generation” Subcommittee of RNC CIGRE, Cand. of 
Tech. Sc., senior lecturer of Department “Automated 
Electrical Systems” of UFU Pavel Chusovitin spoke 
to the participants of the meeting about the program 
of RNC CIGRE C6 Subcommittee activities for 2014. 
He underlined that the document had been drawn with 
account for the R&D tasks established during the 
discussion.


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Construction of small-scale generation facilities with their connection to public distribution grids has recently become a world-wide trend, which is actively promoted by government programs on “green energy” development. However, with all advantages of renewable energy sources, their connection to the energy system in long term aspect still arouses many questions. For instance, lately in the energy community one can frequently hear experts airing concerns about the fact that wider integration of small scale and distributed generation facilities creates difficulties in controlling energy system operation and ensuring system reliability, as, comparing to conventional generation, such energy facilities are much less sustainable.

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