книги / Innovative power engineering

return pipeline (if compared to the approved temperature chart and consumption of the mains water).

Obtained and proven by the analysis conclusion: necessary measures intended to adjust the heat supply system of the town at present are maintained in proper condition.

Hydraulic calculation of main network pipelines

The calculation shows unsatisfactory hydraulic operation mode for certain localities:

Available head of the consumers of the upper zone of pump station is 8-9 m of water column which is unstable for normal work of tempering valve units of the consumers.

Minimum pressure in the supply pipeline of the private residential area units from PA-11 plant amount 26 m water column which is less than boiling pressure of the heat transfer medium under

the rated temperature. Maximum allowed temperature of the heat transfer medium under the rated pressure in the plant is 135 ° , which

is in compliance with the preset temperature trim.

Rated piezometer chart from Permskaya GRES power plant to thermal chamber No.110/5 sheet 1 (Fig. 5).

Fig. 5. Rated piezometer chart from Permskaya GRES power plant to thermal chamber No.110/50 sheet 1

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Rated piezometer chart from Permskaya GRES power plant to thermal chamber No.110/5 sheet 2 (Fig. 6)

Demonstrates the instability of operation of the heat network in the upper area of the pumping station

Fig. 6. Rated piezometer chart from Permskaya GRES power plant to thermal chamber No.110/50 sheet 2

Proposals for enhancement of reliability of the heat supply system of the town

Based on results of the description and hydraulic calculation of the main heat supply networks it is proposed as follows:

Perform overhaul of the heat supply network and to replace pipes which are in operation for more than 30 years.

Increase pressure 1 at the output of Permskaya GRES power plant followed by adjustment activities of the consumers of the top zone of the pump house.

In order to improve the heat supply system reliability and survivability it would be better to construct the 3rd supply pipeline 1Dn 500 at the area from booth No.3 up to arbitrary point No.65.

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Isolation of emergency operation models

Recommendations regarding 'Isolation of situations' covered more than 30 various emergency operation modes and three proposals for installation of additional valves, one of the most significant examples is:

Installation of additional cut-off valve in a pipeline Dn 700 close to booth No. 0 aiming to split the heat supply system of the town into two lines of Dn 500 during summer operation.

Energy saving. Recommendations

•XZ[`^VcfZV_[` [a VWX ydu_g_[` V[ ]c[u_iX udc_[f^ []V_[`^ a[c working 3-Z_cZf_V]_]XdV VWX^_VX[aVWXydu_g_[`V[ ydu_g_[`O=

1Du700 / 2Dnom500, 1Du700 / 1Du500, 1Du500 / 1Du500. In interheating period, to reduce heat losses in this sector it is advisable to work on the scheme 1Du500 / 1Du500.

To eliminate forced heat to the central heat supply station between the outside air temperature –10 °C and above, the stabilization of disposable pressure of subscribers, it is recommended not to switch off the pump on blending thermal point before the end of the heating season.

Proved efficiency of the proposed measures

These measures will allow to exclude summer heat losses in one supply pipeline Dn 700 (length exceeding 3 km) amounting to 2332.2

Gcal per year.

Saving for the heat transfer company (Client in the project) will amount to $ 30 172.89 per year.

Conclusion

Within the framework of the project heat losses were calculated for each rated mode of heat delivery and heat consumption.

This calculation is one of the most important final results, since the values of heat losses are introduced into cost rate for heat energy transfer from the source to the end users.

Measures aimed at cutting such heat losses will allow to significantly reduce the cost for the transfer of heat energy.

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References

1.About energy saving and energy efficiency improvements and about modification of certain legislative acts of the Russian Federation: the federal law from 23.11.2009 N 261-FL: ed. by 29.12. 2014 // Consultant Plus [Electronic resource: reference legal system: documents and comments: touring. inf. resource]. – Professional version, network. – Moscow, 1992.

2.About organization of heat supply in the Russian Federation and about modification of some acts of the Government of the Russian Federation: Governmental order of the Russian Federation dated August 8, 2012 N 808 // Consultant Plus [Electronic resource: reference legal system: documents and comments: touring. inf. resource]. – Professional version, network. – Moscow, 1992.

3.About the procedure for determining the standard process losses for heat transfer, heat transfer medium, norms of specific fuel consumption in the production of thermal energy required reserve of fuel for thermal energy sources (except for sources of thermal energy, functioning in the mode of combined production of electricity and heat), including for the purpose of state regulation of prices (tariffs) in the heating sector: Order of the Ministry of Energy of Russia from 10.08.2012 N 377: ed. By 22.08.2013 // Consultant Plus [Electronic resource: reference legal system: documents and comments: touring. inf. resource]. – Professional version, network. – Moscow, 1992.

4.Rulebook "Heating networks" actualized revision SNIP 41-02-2003 // Consultant Plus [Electronic resource: reference legal system: documents and comments: touring. inf. resource]. – Professional version, network. – Moscow, 1992.

5.Rulebook “Water supply. External networks and facilities” actualized revision SNIP 2.04.02–84* // Consultant Plus [Electronic resource: reference legal system: documents and comments: touring. inf. resource]. – Professional version, network. – Moscow, 1992.

6.Startup and operation of the water heating networks. Directory / V.I. Manyuk [et. al.]. – M.: Stroyizdat, 1988.

7.Nikolaev A. Design of heating networks. Directory designer. – M.: Stroyizdat, 1965.

8.Water heating networks: a handbook on the design. / I.V. Belyaykina [et al.]. – M.: Stroyatomizdat, 1988.

9.Citycom [Electronic resource] / Publishing house «Citycom». – Moscow, available at: http://www.citycom.ru

10.Information system for heat supply [Electronic resource] / Publishing house «ROSTEPLO.RU» – Moscow. – URL: http://www.rosteplo.ru

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OPTIMIZATION COMPLEX SYSTEMS

OF RENEWABLE ENERGY SOURCES (RES) BASED

ON COMPUTER PROGRAM “VIZPRORES” (RUSSIA)

V.I. Velkin, S.E. Shcheklein, K.S. Denisov

Ural Federal University

The approach to an application creation for calculation and optimum unit commitment of the integrated energy system based on the renewable energy sources is examined in the article. The optimization is based on the consideration of multifactor mathematical model representing a “black box”. The result of the present model examination is the creation of an application for calculation of efficient energy system with the equipment definition and the installed power of each type of RES. The performance criterion is the minimal production cost of 1kW*h of energy by the integrated system of RES on average per year. The special feature of the application is a strict lock-on on future RES energy complex location and with regard to stochastic climatic characteristics (wind speed, insolation and temperature).

Keywords: renewable energy, renewable energy sources (RES), RES optimization.

Nowadays more than 12 % of all the energy in Europe is produced by renewable energy sources (RES). 15 years ago this index was less than 0,1 %. However, despite increase of volume, the production cost of 1kW*h of electric energy by RES is high and requires the search of new solutions for increasing a competitive ability in relation to conventional sources.

To increase the efficiency of integrated energy systems based on the RES, the work on equipment definition and capacity optimization is in progress worldwide. The similar problem is solvable through the variety of mathematical models of energy systems and the relevant software, for example, «Homer» (USA) [1], «RETScreen» (Canada) [2] or Skelion [3].

Setting of the problem

The purpose of the product under development is to calculate and select the optimal RES equipment definition of integrated energy system with regard for the second moment of distribution (dispersion of

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production cost of kW*h). The search is implemented by the consideration of multifactor mathematical model representing a “black box” – object with RES complex (cluster) (see Fig. 1).

Fig. 1. Scheme of multifactor discrete mathematical model of RES cluster

In practice the purpose of multifactor experiment is to determine dependence for a discrete stochastic model:

The problem is the selection of xk with the “minimum risk” and minimum production cost of 1 kW*h at the following constraints:

x0 + x1 + x2+…+ xn =1; x0 r0 + x1 m1+ …+ xn mn = A;

A< r0; xi + 0, i 0,1,...,n

A – an acceptable level of the average cost of 1 kW*h, produced by the RES cluster (A< r0); m = M(Y/a) = x0 r0 + x1 m1+ x2 m2 – an average cost of energy, produced by RES cluster in a unit time; r0 – a direct operating cost of disel generator in a unit time (includes the equipment cost as well as cost of handling labor); Y/a = x0 r0 + x1 Y1+ x2 Y2 +…+ + xn Yn – an energy cost, produced by cluster in a unite time (it is a random variable, whereas the first component on the right is not random).

As the target function of the mathematical model of RES cluster was taken the quadratic function from x1, x2,…, xn of the following type:

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i 1 j 1

where i – a fraction of the installed capacity of each type of renewable energy sources, included in RES cluster; Y/a – an energy cost, produced by cluster in a unite time; ij – a sample covariance, calculated on

sampling collection for Yi, Yj.

This is the convex-programming problem, which can be solved using the “finding solutions” module in Excel. The result is a vector (x0, x1, …, xn), setting an effective RES cluster equipment definition. As applied to the RES cluster this is a solving for optimum of fraction capacity balance DG, WT, PC, … n.

Optimality criterion is the minimal production cost of kW*h electric energy by all types of the equipment per year [4].

Functional characteristics of “VizProRES”

The application for RES optimum unit commitment “VizProRES” is made in “Adobe Flash Professional CS6” in programming language Action Script 3.0. [5] and is exported to the “EXE” format for the start convenience on any computer. The runtime environment is presented in the Fig. 2.

Fig. 2. Runtime environment “Adobe Flash Professional CS6”

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The “VizProRES” application makes it possible to choose the effecttive RES equipment complex including wind turbine (WT), photoelectric converter (PC), small hydro-electric power station (sHEPS), biogas unit (BU) and disel generator (DG), as well as to calculate the ideal installed capacity of each element and for the given location.

Application operation description

At application start appears a start screen as presented in the Fig 3. To data input is necessary to activate the relevant field, upon which opens a user-friendly input window (Fig. 4). The user may choose types of equipment and characteristics. To download daily data per year of sun insolation, wind speed, water consumption from a pond, river flow rate, in a relevant field is necessary to input data from a “.txt” file, which contains previously created database.

Fig. 3. The application start screen “VizProRES”

In “VizProRES” there is an ability to store the selected data and download of previously input information [5] by pressing the icon “Save the project” or “Download the project”.

The calculation window opens after the input of all the necessary data [6].

Search of optimum RES complex is made by computer blind search of all the possible choices resulting in finding a point corresponding to a minimal production cost of kW*h of electric energy. The determined parameters of RES complex are displayed in text fields.

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Fig. 4. Raw data input window

In “Diagrams and analysis” window (Fig. 5) is made a construction of the diagram of kW*h total cost dependence of calculated equipment definition on its risk in %. Can be chosen the diagram range on the “risk” and “cost” scales, the calculation step and risk step.

The “Risk” parameter displays an irregularity of energy production during a year. The higher is the “risk” parameter the higher is the irregularity of energy production. Zero-risk is possible with only risk-free energy sources, such as disel generator or biogas unit, which energy production is constant in time.

Conclusions

1.The analytical model of efficiency of RES complex system makes it possible to improve the RES cluster on equipment definition and minimum-cost criterion of 1 kW*h production.

2.Usage of the mathematical model of second moment of distribution (dispersion) makes it possible to increase the accuracy of calculation of the optimum RES equipment definition to 20–25 %.

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Fig. 5. Window “Diagram and analysis of RES equipment definition”

3. The choice of the optimum RES type definition with the help of “VizProRES” makes it possible to bring down equipment capital costs and to increase the reliability of consumers electricity supply.

References

1.Lambert T., Gilman P., Lilienthal P. Micropower system modeling with HOMER // Integration of Alternative Sources of Energy, F.A. Farret and M.G. Simões. – Wiley-IEEE Press, 2006. – P. 379–418.

2.RETScreen International: Results and Impacts 1996-2012 / G.J. Leng, A. Monarque, S. Graham, S. Higgins, H. Cleghorn // Minister of Natural Resources Canada. – 2004. – URL: http://www.retscreen.net/ang/impact.php.

3.Skelion: A solar energy design plugin for SketchUp, December, 2011. – URL: http://skelion.com/

4.Adobe Systems Incorporated. Usage of ActionScript™ 3.0 components. – Adobe Systems Incorporated, 2008. – P. 198.

5.Velkin V.I., Loginov M.I., Chernobay E.V. Development of mathematical model and application for RES cluster calculation “Energy and source efficiency of low rise buildings”. – 2013. – P. 142.

6.Vasil’ev Y.S., Kubyshkin L.I., Kudryasheva I.G. Computer-aided technologies in scientific research and designing of objects of renewable power generation. – Publishing house of Polytechnic university, 2008. – 259 p.

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