Dissert F4 (revizuit Mdc) [309044]

TRANSILVANIA UNIVERSITY OF BRAȘOV

FACULTY OF ELECTRICAL ENGINEERING AND COMPUTER SCIENCE

DEPARTMENT OF ELECTRICAL ENGINEERING AND APPLIED PHYSICS

MASTER STUDY PROGRAM: ADVANCED ELECTRICAL SYSTEMS

Eng. ARONICA Ruben

DISSERTATION

MASTER STUDIES

Scientific coordinator:

Prof. Dr. Eng. Marius Daniel CALIN

BRASOV

2018

TRANSILVANIA UNIVERSITY OF BRAȘOV

FACULTY OF ELECTRICAL ENGINEERING AND COMPUTER SCIENCE

DEPARTMENT OF ELECTRICAL ENGINEERING AND APPLIED PHYSICS

MASTER STUDY PROGRAM: ADVANCED ELECTRICAL SYSTEMS

Eng. [anonimizat].

[anonimizat] a wind turbine.

Scientific coordinator:

Prof. Dr. Eng. Marius Daniel CALIN

BRASOV

2018

Table of Contents

CHAPTER 1 3

1.1. Abstract 3

1.2. Introduction 3

1.3. The wind’s mathematical equations 4

1.4. Wind turbine geometry 6

1.5. Control and regulation of WT 7

1.5.1. Stall regulation 7

1.5.2. Pitch regulation. 8

1.5.3. Yaw regulation. 9

1.6. Turbine types and terms 9

1.7. Wind energy extraction 11

CHAPTER 2 13

2.1 Romanian energy sector 13

2.2 Wind potential energy analysis in the centre region of Romania 14

2.3 The average annual wind velocity in Romania 14

2.4 Central region’s geographical, physical characteristics and climate analysis 15

CHAPTER 3 25

3.1 Single-phased motor mathematical model 25

3.2 Emulation of a wind turbine 27

3.3 Barriers to develop investment projects in renewable energy 33

References 36

CHAPTER 1

[anonimizat]. Therefore, the paper includes in the first chapter the most important mathematical equations regarding the wind’s force, a [anonimizat] a wind turbine and how electric energy extraction mathematical model. The second chapter treats Romanian energy sector …why? and the wind potential analysis in the centre region of Romania why?, which is followed by the third chapter which aims to simulate a wind turbine to prove out (WT) using a WT emulator so as to confirm the working principle and measure the most important parameters which are – a few ex for a WT.

Introduction

The wind’s force is a [anonimizat] a weather hurricane. Historically, [anonimizat].

[anonimizat] a [anonimizat]. Electricity produced from the wind produces no CO2 emissions and therefore does not contribute to the greenhouse effect. Wind energy is relatively labour intensive and thus creates many jobs. The wind turbines main drawback is the noise when they produce electricity. [13. MAR – 2008]

Fig.1.1 Highlighting of aerodynamics concept [VI]

[anonimizat], respectively the air’s interactions with solid materials.

[anonimizat]’s [anonimizat]. [anonimizat], [anonimizat].

The wind’s mathematical equations

Considering w was the wind’s speed and p the dynamic pressure gives the following equation:

1.1

, where ρ is the air density in kg/m3. The density of the air depends on the atmospheric pressure and on the air’s humidity. If the wind hits an S surface, such as the boats sail, the potential (p) pressure will become mechanical energy used to pull the boat further. If S is the surface area, the following relation gives the F wind force:

1.2

Considering the displacement on the x-axis, the following relation computes the mechanical work developed by the wind’s force:

1.3

The P power developed by the wind in a τ time interval can be determined:

1.4

, because

1.5

Fig.1.2 Wind’s energy kinetic force calculus scheme

To compute the winds kinetic force in the 1.2. Figure, considering an arbitrary V air volume, closed by an arbitrary S surface on x length, which is in the wind’s direction, and the surface is normal of the wind’s direction, the air’s volume is:

1.6

Considering air’s density as ρ, the m wind’s air mass will be determined:

1.7

The air’s mass kinetic force (Ec) in this case computes by the following formula:

1.8

Moreover, the following relation gives the kinetic power developed by the wind in time:

1.9

All these cases are in ideal consideration, without losses. In real case, the technical performances of the equipment determines the η efficiency.

1.10

, where the r indices mean’s the real size compared to the theoretic ideal dimensions.

Wind turbine geometry

Geometrically spoken the wind turbine’s blade has an elongated rectangle form. The radius is the distance between the hub and the blade’s peak, shown in Figure 1.3.

Fig.1.3 The rotor and blades of a wind turbine [I]

If the transversal section is considered, the form of the blades is asymmetrical. This structure helps the wind to hit the bolded part of the blade; this is the so-called front of the blades. These profiles are the aerodynamic profiles (fig.1.4).

Fig.1.4 Wind turbine’s blade design [1 ABB-1959] 7.[GLA – 1935]

Wind turbine blades are long and slender structures where the spanwise velocity component is much lower than the streamwise component. [XII]

Control and regulation of WT

The control system ensures that the turbine operates within the design range; it keeps the rotational speed within a certain range; yaws the turbine; keeps the power output within a certain range and starts or stops the turbine. The control system can ensure a smooth power output P(t) and may optimize the power output at lower wind speeds. To limit the power at high wind speeds the following three strategies are used:

Stall regulation;

Pitch regulation; and

Yaw control.

The stall regulation is the simplest of all because fixes the blades to the hub. Pitching in this case is not possible. A stall regulated wind turbine operates almost at constant rotational speed, and thus, the angle of attack increases as the wind speed increases. On a stall-regulated wind turbine, an asynchronous generator is often used. The rotational speed of the generator in an asynchronous generator’s case is:

2.1

, where fgrid is the grid’s frequency and p denotes the number of pole pairs. Because the rotational speed of the generator is higher than the rotational speed of the rotor, a gearbox used between the generator and the rotor is necessary.

Fig.2.1 A typical torque characteristic for an asynchronous generator

The pitch regulation makes possible to pitch the entire blade and thus to change simultaneously the angles of attack along its entire length. The result-sketch of one way for pitch control is in figure 2.2.

Fig.2.2 Stall regulated wind turbine starting at high wind speed:

Elkraft 1MW demonstration wind turbine at Avedøre, Denmark.

A pitched blade can act as an aerodynamic brake and it is no longer necessary to include tip brakes as on a stall-regulated machine. By pitching the entire blade, it is possible to control the angles of attack and thus the power output. Power reducing means decreasing the angles of attack and by pitching the leading edge of the blades up against the wind.

At yaw regulation, instead of limiting the power output using pitch regulation, the control is at the turbines yaw. On normal pitch regulated machines, it is common to have a yaw drive, which is trying to rotate the nacelle to minimize the yaw misalignment in order to get as much air through the rotor disc as possible. In high winds, the rotor turns out of the wind to limit the airflow through the rotor and thus the power extraction. For example, the old Western mills used yaw control. For the Nordtank NTK 500/41 machine in yaw regulation, the results are in Figure 2.4.

Fig.2.4 Constant speed versus variable speed

A wind turbine is equipped with an asynchronous generator forcing the blades to rotate at a given speed. Wind turbines are running most efficiently at a wind speed Vo of approximately 7m/s as displayed at Figure 2.4 [1. ABB, 7. GLA, 13. MAR – 2008]

4.[DAN – 2012] [MIH – 2012]

Turbine types and terms

The names of different types of wind turbine depend on their constructional geometry, and the aerodynamics of the wind passing around the blades; also called aerofoils. Fig.4.1 shows a blade section of a horizontal axis wind turbine’s blade. Velocities and forces at a section of a rotating turbine blade. (a) Front view of horizontal axis turbine blade, rotating section speed v; (b) Perspective view, showing undisturbed wind speed u; (c) Section view from the blade tip, showing v in the plane of rotation and distant wind speed u.

Fig.3.1. Wind turbine’s blades

Figure 3.2 gives the classification of possible wind devices.

Fig.3.2 Classification of wind machines and devices. (a) Horizontal axis. (b) Vertical axis. (c) Concentrators. [MAR – 2008]

Wind energy extraction

In the undisturbed state a column of wind is upstream of the turbine, having an A1 cross sectional area of the turbine disc, has the following kinetic energy that passes per unit of time:

4.1

, where ρ is the air density and u0 the undisturbed wind speed. This is the power in the wind at speed u0.

Fig.4.3 Power in wind.

In Fig.4.3, the mass of column is ρAu0, and the kinetic energy equals with the given equation:

.

The air density (ρ) depends weakly on height and meteorological condition, because wind speed generally increases with height, affected by local topography, and varies greatly with time. A typical value for ρ is 1.2kg m-3 at sea level, and useful power can be harnessed in moderate winds: u0 ∼ 10ms−1 and P0 = 600W m−2.

Theoretically, the air’s velocity is constant. This means that the same air passes through the turbine in laminar flow as shown in fig.4.4

Fig.4.4 Betz model of expanding airstream

Treat the rotor as an ‘actuator disc’, in this case, across which there is a change of pressure as energy is extracted and a consequent decrease in the linear momentum of the wind. Perturbations to the smooth laminar flow is not a considering problem here, although they undoubtedly occur because of angular momentum is extracted and vortices in the airflow occur.

Area A1 is the rotor swept area, and A0 and A0 areas enclose the stream of constant air mass passing through A1. For energy extraction mathematic modelling, must be follow the steps given:

Step 1: To determine u1. The F force or thrust on the turbine is the reduction in momentum per unit time from the air mass flow rate .

4.2

This force applies by an assumed uniform airflow of speed u1. The 4.3 relation gives the power extracted by the turbine:

4.3

The loss in energy per unit time by that airstream is the power extracted from the wind calculates by:

4.4

Equating PT and Pw the following expression found out is:

4.5

, hence

4.6

Thus, according to this linear momentum theory, the air speed through the activator disc cannot be less than half the unperturbed wind speed. [12. JOH – 2006] [MAR – 2008]

CHAPTER 2

Romanian energy sector

Romania is trying to increase usage of renewable energy from 17.8% in 2005 to 24% in 2020 to reduce emissions of greenhouse gases by 21% and to use 10% biofuels in the composition of fuels by 2020. [17.] [24. TUD – 2009] [24. YOG – 2016] [2. BRA – 2012] [11. JEF – 2012]

In the present, in Romania the energy is produced primarily based on coal-plants, natural gas and oil, plus energy from hydropower and since 1996, nuclear power. There are three major consumers: industry, households and transport. All this sector is regulated by the National Regulatory Agency in the Energy Field – ANRE (abbreviation in Romanian), which “has the mission to create and enforce regulations necessary for the energy sector, heat and natural gases market functioning.” (http://www.anre.ro/)[II]

Because the use of these sources is restricted, therefore the potential is lower than that presented in Table 1. That is because technological barriers, implications of economic efficiency and the environment. All values are in thousands toe, this measure unit meaning thousands of tones oil equivalent.

Table 1. Annual potential of energy from renewable sources. Source: PNAER (National Plan for Taking Action on Electrical Domain in RES)

Romania produces and consumes energy from renewable sources as shown in the table below:

Table 3. Production and consumption of energy from renewable sources in 2002-2008, Romania2 2 Eurostat

Observe that in certain years, gross internal consumption exceeds renewable energy production. 3.[COR – 2011]

Wind potential energy analysis in the centre region of Romania

The available wind energy on a Mondial scale approximates to be 57.000 TW/year, where the offshore contribution estimates 25.000-30.000 TW/year. Therefore, theoretically spoken, wind energy could cover all energy there is necessary.

The question is how will Mondial energy consumption will be? The fact that energy consumption is always in increase is obvious. That is why the International Energy Agency provides an approximated 5.8 million megawatts until 2020 from 3.3 million in 2000.

The average annual wind velocity in Romania

Orography and the airs thermal stratification directly influences the wind’s velocity is. Thus, on the mountain zone the average annual wind velocity is 8 – 10 m/s on the Carpathian peaks (2000 – 2500 m), at lower altitudes it will have a 6 m/s at 1800 – 2000 m and it reaches 1 – 2m/s in the depression zone. In the Carpathic interior curve, in Moldova the wind’s speeds are 4 – 5 m/s, and measuring the annual average top speeds in the eastern part of the country, in Câmpia Siretului the speed stands at 5 – 6m/s, and at the Black Sea’s shore (6 – 7 m/s). The highest wind speed values measured in Romania are on the mountain peaks. In Podișul Moldovenesc, Bărăgan’s north-east and the mountains of Dobrogea, where the winds velocity gets up even to 40 m/s. Likewise, at the Danube’s Delta, the Transylvanian plateau and in the northern part of the vest plain and Mureș rivers lane the annual wind speeds are between 20 – 30 m/s. Based on the evaluations and the interpretations of the data resulted from measurements, the energetic potential in Romania is the most favourable on the Black Sea’s shore, at the mountain zones and at the Moldova and Dobrogea’s plateau.

Fig. 2.1 Average annual wind speed in Romania

Central region’s geographical, physical characteristics and climate analysis

In this region is the interior of the Carpathian curve, formed from six counties: Alba, Brașov, Covasna, Harghita, Mureș and Sibiu (Fig. 2.2). This region’s relief contains important parts from the Romanian Carpathian Mountains, the Transylvanian plateau and the contact depressions between the hills and mountains. The mountain-zone takes over 47% of the given territory; here are the well-known peaks: Moldoveanu (2544 m) and the Negoiu (2535m).

The central region of Romania has a shielded climate because geographical means. In this zone may exist some wind also thanks to the Atlantic Ocean. Using the Geographic Information System (GIS), the wind potential for the central region of Romania is analysed. To make the study complete and to complete the most important meteorological parameters, the Climatologic Atlas of Romania (1970) was used. This study uses two interpolation methods: Natural Neighbours and the Kriging method. Kriging is “an advanced geostatistical procedure that generates an estimated surface from a scattered set of points with z-values. Unlike other interpolation methods in the Interpolation toolset, to use the Kriging tool effectively involves an interactive investigation of the spatial behaviour of the phenomenon represented by the z-values before you select the best estimation method for generating the output surface”. [V.] The Natural Neighbour method is “a geometric estimation technique that uses natural neighbourhood regions generated around each point in the data set.” [X.]

To verify the zones that have wind potential it is important to consider the following criteria:

constant wind speed at the wind turbine

the wind turbines should be mounted on gentle hills and round heights

a god air circulation over the hole year

avoiding the rough terrain

consult the meteorological maps with the high annual frequency of the wind

lower the wind variations in time as much as possible.

In modern world, the extraction of power from the wind with modern turbines and energy conversion systems is an established industry. Thus, manufacturing machines is possible with different capacities, varying from tens of watts to several megawatts, and diameters of about 1 m to more than 100 m. Based on these measurements the following maps had resulted (Fig. 2.3 – Fig. 2.9). These maps shows the average annual wind speed (Fig 2.3); the atmospherically calm, small speed, medium speed and high wind speeds (Fig 2.4); the dominant wind’s average speed (Fig 2.5) evidenced for the 4 values given above (Fig 2.6); the wind’s potential map (Fig. 2.7); the detailed wind’s speed and the wind potential map considered in Romania’s central part (Fig 2.8 and Fig 2.9).

Fig. 2.2 County map of Romania, Central Region of Romania marked with red dots. [III]

Fig. 2.3 Central Region of Romania. Annual average wind speed given by the dominant direction of the wind.

Fig. 2.4 Central Region’s average wind speed categorized by four (4) major values: atmospherically calm, small speed, medium speed and high wind speeds.

Fig. 2.5 Central region. Average dominant wind’s speed frequency map.

Fig. 2.6 Central region. Wind speed’s frequency map evidenced for the 4 dominant classes.

Fig. 2.7 Central region. Wind’s potential map

Fig. 2.8 Central region wind’s speed (m/s)

Fig. 2.9 Central region’s wind potential map [21.REG – 2010]

Negoiu Impex project manufacturer executed a wind potential evaluation in Brașov area. The considered zone was Brașov, its vicinity, and Poiana Brașov. Two zones found to be interesting: the Tâmpa and the Postăvarul peak. For this study, the ANM map (1Administratia Națională de Meteorologie (RO) => National Meteorological Administration System (EN) [IX.]) was used which contained the average wind speed at 50m altitude and a map at 60m developed by Al-Pro German Company. An investment in the given cases to costs between 30.000 – 50.000 Euros.

Fig. 2.10 Studied zones viewed on Google Maps (marked with red dots)

After a brief study, the conclusions are the following:

In the case of Tâmpa, at 120m the wind speed is 4,1m/s. This is not a recommended for such a financial investment, because it could return only in 39.3 years.

Considering the Postăvarul peak, using the, the Al-Pro German (http://www.al-pro.eu/) group’s map at 60m and 120m, the annual average wind speed is much higher than at Tâmpa: 6.1m/s at 60m and 7m/s at 120m.

Quoting the information from 3TIER Company (https://www.3tier.com) it is found out that at Postăvarul there is a 74% wind potential, which is equal with the one from Fântânele, Cogealac, Doborgea, where already have been made large investments that cumulated up to 400 million Euros.

Fig. 2.11 Comparison between Postăvarul and Fântânele

[18. OCT – 2012]

CHAPTER 3

Single-phased motor mathematical model

Since in the emulator implements a single-phased asynchronous motor, a mathematic model of the single phased induction machine is studied.

Modelling of a single-phased induction machine, developed for the commonly type, refers to a squirrel-cage motor. Building the model means on one distributed stator winding and two equivalent rotor windings, modelling the squirrel cage. The single-phase induction-machine does not produce a torque at standstill; in this case, it needs an auxiliary winding to produce a non-zero starting torque that will cause the shaft to accelerate to near synchronous mechanical speed at no load. A fifth-order differential model of the single-phase induction motor in rotor (a, b) coordinates is given below [4. DAN – 2012].

3.1

3.2

3.3

3.4

3.5

Where the label “s” denotes the stator winding, and the labels “ra” and “rb” denote the rotor phase-a, and phase-b windings. The variable λs is the stator flux and λra and λrb are the rotor fluxes of phases a, and b. The electrical angle between the stator winding and the phase-a rotor winding defined as θ, and the electromagnetic torque and the mechanical load torque are defined as Te respectively Tm.

The flux relations given by the following equation are:

3.6

Where Lls and Llr are the stator and rotor leakage inductances and Lms is the stator magnetizing inductance. For an electrically linear machine, the magnetic co-energy is equal to:

3.7

Using equation 2.6, the co-energy, expressed in terms of inductances is:

3.8

The electromagnetic torque developed by the machine given by the equation below:

3.9

, where θm represents the mechanical angle of rotation related to the electrical angle θ by

3.10

Where p is the number of poles per phase. With these considerations, electromagnetic torque equals

3.11

Emulation of a wind turbine

The present project studies the implementation of a wind-turbine emulator. This has the purpose to enlarge the viewer’s experience about how wind-energy is possible, how does it work and how energy extraction is possible. This layout uses a kitchen hood’s fan (Fig.3.3), the AC motor and command system from the same hood (Fig. 3.1; Fig 3.2), a DC fan (Fig.3.4) and a box (Fig.3.5), which holds all these components.

The construction of the box is in such manner, that the wind has the best output speed. The top of the box also has a grid (fig!). The grid enables slight variations of the electric energy created by the flowing air. Gradually closing this vent blocks the airflow, so it cannot come out. This leads heat to increase, especially in the inside of the motor, leading to possible damages in time.

The WT emulator components, highlighted in the following figures are given.

Fig.3.1 The main rotor

Fig.3.2 The main stator

Fig.3.5 The wind generator ensemble – view from interior.

A wind turbine emulator is as shown in fig.

The system has the following main components:

AC monophased motor;

main fan (on the motor’s shaft);

switch;

secondary fan (resembles the wind turbine’s blades).

All the components are in a wooden case (Fig.), which has the following functioning mode:

The main motor, plugged to the AC power supply (the grid).

The main fan, started by a switch will create a strong air-blow.

Therefore, the secondary fan will start rotating, thus creating DC voltage.

The secondary fan connects to a simple LED lantern. The lantern’s purpose is to confirm the working of the whole.

The switch has two operating modes: one for low speed, and one for the highest speed possible for the motor. Therefore, at lower speed there are 1400 rpm’s, while at the highest speed 2450 rpm. This makes possible a detailed study over wind energy potential even at a lower scale.

The main motor parameters are given:

Table 3.1

The secondary DC fan output parameters, the following table highlights the results extracted from measurements:

Table 3.2

The speed of the wind, measured in Brașov area is for this study’s relevance. This is possible by using the Zephyrus Android application from Play Store®, which uses the mobile phone’s microphone to compute the speed of the wind, therefore considering a 2% imperfection at these measurements is a must-have. The measurements that resulted are below as graphic charts. Places where measurements took place:

Astra Marketplace (Fig…);

Bucharest Street (Fig…);

Tâmpa peak (Fig…);

Postăvarul peak (fig…).

The graphic chart’s main window has the following components: momentary wind speed; smallest wind speed; average value calculated considering all the measurements and maximum wind speed.

@ Astra marketplace the following data had been obtained

@ Bucharest street the following data had been obtained

At tâmpa peak At Postăvarul peak

All measurements had been at ground level, especially when the wind blew stronger then usually.

The wind’s speed created by the main motor’s fan gave by the same application is shown.

Wind speed at 2450 and at 1400 rpm

Because the fan can rotate with two different speeds, the LED lantern’s light flux has to be different because of the two rotational speeds. The flux of the light, measured using the Light Meter app from Play Store® shows the results as it is below:

Light’s flux at 1400 rpm Light’s flux at 2450 rpm

This energy could be used to power the telecine.

In this study, important is the average light flux, which is 439 lx at 1400 rpm, and 588 lx at 2450. Therefore, there is a difference of 149 luxes, a considerably large difference. Therefore, the LED lantern will have a brighter light at 2450 rpm.

For a simpler visualization of the emulating system, a virtual 3D wind-emulator model is proposed. This model resembles the emulator’s working principle, as will be shown.

Fig. Virtual emulator. 1 – DC fan (12V), 2 – main wind generator fan, 3 – two speed switch, 4 – main motor, 5 – air-out grid.

Fig. shows the wind’s path in the emulator.

In the emulators design the path of the wind was optimised to maximum capacity.

Barriers to develop investment projects in renewable energy

The emulator used in this study did not consider all the barriers that could appear in real life when it comes about building a wind-plant. For example, the wind’s force in this case is constant (see above, at Fig. …). Therefore, consider the following barriers in developing investment projects in RES, mostly at wind energy.

There are many barriers, which constitutes in most of the challenges for development of investment projects in the energy sector, especially in developing projects that focus on renewable energy.

Firstly, mention administrative barriers:

Insufficient spatial planning,

Nimby attitude (it stands for “not in my back yard”),

Troublesome procedures (authorization time),

Too many authorities involved, and the list may continue.

Secondly, economical barriers:

The lack of economies of scale in production of technology for obtaining renewable energy;

The infrastructure.

Thirdly, Technological barriers examines lack of technical skills, lack of information on new technologies, overall complexity, maintenance of the components, choosing the wind turbine’s proper regulation type and many others.

Fourthly, a few of the market barriers are the size of investment project cost of transportation for energy from renewable sources, restricted access for new competitors, etc.

As any technical system, the wind-energy harnessing gains advantages and disadvantages.

Secondly, the most widely emphasised pro and contras are the following.

Pro – arguments:

renewable energy;

low maintenance cost;

medium price;

less residual waste materials.

Contra – arguments:

volatile production;

hard to estimate;

its noise disturbs the environment;

birds are endangered;

drying of the soil.

At last, but not least, market barriers could stand in the way of implementing a renewable energy system (this applies to wind energy to).

the size of investment projects;

cost of transportation for energy from renewable sources;

consumers choices;

price formation rule;

All these represent an obvious barrier, but some could become strengths too. For example, if lack of technical skills is a problem in the present, in the future could be (must be) solved.

In conclusion, the present project deals with the study about the wind energy as potential solution when it comes about implementing RES in Romania.

Demonstrated at a smaller scale by the emulator revealed above brings the following notices. The results demonstrates the possibility of harnessing wind because the emulator’s highest wind speed is 5.8 m/s, notable close to 6.1m/s measured at Postăvaru peak. The results gained demonstrates the possibility for a LED lantern to lighten at 588 luxes. At this scale this is a considerable significance, which can be transposed in 3V at 10 mA DC.

Especially in Brașov area, at the Postăvaru peak, it is a great possibility to build up a number between two and five wind plants. This solution, energetically spoken could optimise the teleferic sistem by creating energy for this. Although this solution costs, it is a feasable answer for Brașov, especially because this would mean an energetic development, so as to lifts Brașov at a higher cultural position. This would bring vast results, as encouraging development of other similar projects, growing tourist attraction, affordable monetary amortization, and many others. Moreover, this project would cost between 30.000 – 50.000 Euros, which is not a too large amount compared to 400 million Euros invested at Fântânele. Brașov city could become a flourishing town in Romania by implementing such a project.

The barriers of such a development are great ones, but there are not impossible to break. Some of them could be undone in a short time, some of them only in a long term. The existence of barriers is an inevitable truth therefore no reasonable project should stop on these terms.

The wind is always available. The problem is that the society does not use it totally. It is time to change!

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