10 / 01 / 2014 - 10:48 — Grażyna Paulina W...

Grażyna Wójcik , преподаватель

Jakub Woźniak, студент

Warsaw University of Life Science, Польша

Участник конференции

**G110**

*The authors present criteria availed in taking an investment decisions are characterized by long life. Macroeconomic aspects of Poland wind energy sector/industry have also been described. The article is based on numerous press and scientific articles, as well as reports.*

*Due to the fact that investments related to a construction of a wind farm are characterized by a long payback period to profitability assessment, the authors recommend discount methods. The authors suggest using the concept of weighted average cost of capital to determine a discount rate. They recommend a sensitivity analysis and value at risk to asses an impact of certificates of origin prices and productivity of wind farms. Furthermore, the concept of Cash Flow at Risk is counseled to estimate a value at risk.*

*The authors describe most common methods used for an analysis of investment projects. Bearing in mind crucial investment decisions for the future of a company, a decision taken should be based on more than one criterion. The most commonly used criterion for assessment of investment projects are NPV and IRR and less commonly DPP and PI. The condition for accuracy of estimates of each and every criterion is an appropriate determination of cash flows, a discount rate and duration of an investment.*

**Keywords: **wind energy, investment profitability, discount methods, criterion of profitability

**Introduction**

Poland energy sector/industry including wind energy segment seems to be particularly interesting for foreign investors. Depreciated infrastructure, steady growth in electricity demand for households and the economy as a whole causes huge resources to be exploited in Poland over the next few years.

An investment in wind energy segment is not only a chance for foreign entities, but primarily for Polish economy. Owing to development of this segment in subsequent years production of zero emissive energy will be possible and Polish energy security will improve. Multimillion- investments will be a significant source of income for state budget, and have a positive impact on a creation of new jobs.

**Literature Review and Hypotheses**

*The wind energy sector/industry in Europe*

During past 12 years in Europe, an increase from a level of 3.2 GW to almost 12 GW of installed capacity in wind power plants was recorded annually (Wind in Power 2012 European statistics, 2013:19, 20). This trend is shown in Fig. 1.

**Fig. 1.Investments in wind power in the years 2001-2012 in Europe**

*Source: own study based on Wind in Power 2012 European statistics, The European Wind Energy Association, February 2013: 10.*

Currently in Europe there are wind turbines with a total capacity of about 106 GW (Fig. 2). The regular leader on energy market is Germany whose share in the European wind energy equals 30%.

**Fig. 2. Total wind power in the European Union.**

*Source: own study based on Wind in Power 2012 European statistics, The European Wind Energy Association, February 2013: 10.*

According to estimates, owing to currently existing installations about 231 KWh of electricity can be generated, which covers 7% of total energy demand in Europe. In 2011, the figure was less than 6.3%. Denmark with its (27%) of energy produced by wind power is the country with the highest ratio of meeting a demand for electricity. The subsequent places are taken by Portugal and Spain, where value of this ratio is 18%

and 17% respectively.

Currently in Poland there are 890 installations that produce electricity by wind power with a total capacity of 3727,03 MW (as of 31.08.2014).(http://www.ure.gov.pl/uremapoze/mapa.html). This means that in the first six months of 2013 Poland already reached the level envisaged by the Ministry of Economy, which was to be reached at the end of 2013 (Ministry of Economy, 2011: 5). Undoubtedly, over the last few years a steady and stable growth in the number of wind farms has been observed (Fig. 3).

**Fig. 3. Installed capacity of wind farms and growth rate of installed capacity in Poland**

*Source: own study based on http://www.pwea.pl/pl/energetyka-wiatrowa/ewi-w-polsce*

Particularly rapid growth of installed capacity occurred in 2012 and amounted to 880 MW compared to 436 MW in 2011, which may be due to the fact that investors wanted to complete their projects before the end of 2012 in order to benefit from old support systems.

Wind energy is the fastest growing segment of renewable energy in Poland. Owing to stable growth of capacity, wind power represents nearly 60% of all green energy market in Poland in terms of installed capacity. Currently operating wind farms produced 3 126 GWh of electricity in 2011, which allowed to meet a demand of almost 2% of the total demand for electricity. Still in 2004, this figure was only 0,1% (http://www.pwea.pl/pl/energetyka-wiatrowa/ewi-w-polsce).

Poland is a country with favorable climatic conditions for conducting activities related to production of electricity using wind. Currently, owing to development of technologies to manufacture wind turbines having an impact on lowering minimum wind speed at which it is possible to produce electricity, nearly two thirds of Poland territory is characterized by appropriate wind conditions. The most attractive areas are located in the north-western part of Poland, where wind speed can fluctuate within 10 m/s (Wind from the East, 2013: 10). Favorable conditions are also along the coast of the Baltic Sea, and in Warmia and Mazury province. Marine areas are excellent investment zones. It is estimated that about 3600 km2 area of the Baltic Sea may be used for a construction of offshore wind farms (Gajewski et al, 2013: 4). In 2012, off the coast of Europe, new wind parks with a total power of almost 1.2 GW came into existence. However, no project of the type has been implemented by now on Polish territorial waters (Wind in Power 2012 European statistics, 2013: 10).

*Macroeconomic aspects of wind energy sector development in Poland*

In 2018 it is planned to add first offshore wind farms with a power of 500 MW. In subsequent years there will be a steady growth in power of offshore wind farms at a level of 500 MW a year so that total capacity is to amount 1.5 GW in 2020. The amount of incurred expenses associated with a construction of wind farms off the coast of the Baltic Sea is estimated to be 20.5 billion PLN. The total value of investments in the wind energy sector in the period of 2013-2020 will amount to over 80 billion PLN. Almost 21.6 billion PLN will be invested in Poland. When it comes to these expenditures is apparent from the connection costs, financial services, installation of turbines or internal construction of infrastructure (The Foundation for Sustainable Energy, 2012: 30).

Capital expenditures in the wind energy sector are a significant part of all expenses allocated for investments. In order to illustrate the above-described trend a value of investments in 2011 in various sectors of Polish economy was listed (Fig. 4).

**Fig. 4. Investment expenditure in the various sectors of the economy in 2011**

*Source: own study based on Statistical Yearbook of the Republic of Poland 2012, Warsaw 2012: 651.*

Corporates (operating in wind energy sector) income tax, in addition to capital investment is an important stream of payments that contributes to Polish economy. The authors conducted the analysis on an amount of state budget revenues from income tax of entities operating in production of electricity from wind in 2012-2020. The following assumption for the needs of this analysis was made: an average value of income tax paid by companies in 2011 amounted to about 98 200 PLN per 1 MW of power. It was also assumed that by 2020 an average value of CIT per 1 MW of installed capacity will not change (Ciżkowicz et al, 2012: 48. 49). In order to estimate future revenues from CIT, energy development scenario was used. It was developed by the Institute for Renewable Energy. The estimated results are shown in Fig. 5.

**Fig. 5. The projection of revenues from CIT to state budget in 2012-2020 in million PLN (constant prices of 2011)**

*Source: own study.*

Owing to wind farms activity, state budget revenues increased by approximately 245 million PLN in the previous year. In subsequent years, there shall be a steady increase in revenues from income tax at a level of about 20.1% per year. In 2019, payments due to corporate income tax will exceed one billion dollars and amount to 1 119 million PLN, while next year they will amount to about 1 276 million PLN. It should be noted that these values are in constant prices as of 2011.

**Method and results**

*The criteria used in making investment decisions*

According to a dictionary of Polish language an investment is a process of allocating funds for reconstruction or increase of property resources (http://sjp.pwn.pl/szukaj/inwestycja). This definition, however, does not fully reflect the essence of an investment and elements that influence it. Jack Hirshleifer in one of his articles described the concept of investment as "...a current renouncement for future benefits. The present, however, is well known but the future is a mystery. Therefore, an investment is a renouncement of something certain for an unknown, uncertain benefit." (The Quarterly Journal of Economics, 1965: 509-536). According to Jack Hirshleifer’s definition the following components of an investment can be numbered: distribution of cash, time, and risk.

In most cases, property investments cannot be implemented using small funds and this causes mistakes to be very costly. Furthermore, the process of investing capital is better described by a company than a structure of equity or liabilities, which in case of many companies are unclear and seem to be very similar. Bearing the above statements in mind, it is assessed that investments play one of the key roles in operation of an organization. The investments determine a company’s position on the market, and decide on its future. First of all, they enable an increase in value for shareholders over a long period of time being the primary objective for operation of any enterprise (CFA Institute, 2012: 5, 6).

Jack Hirshleifer scored aspect of time and risk as the most important features of an investment. On the basis of his words it can be concluded that simple methods are not the best measures that enable to estimate profitability of a project. This is due to the fact that simple methods do not take into account the concept of time value of money. This concept includes categories of risk and time. In some cases, simple methods are used in the initial phase of the investment projects’ selection. This is due to the fact that on the basis of simple calculations, simple methods allow projects that carry the highest risk to be rejected (Jajuga and Jajuga, 2006: 9). Due to the fact that investments related to a construction of a wind farm are characterized with a long payback period, only discount methods were described.

In order to make an investment decision using discount methods it is necessary to ensure comparability of measured economic values. For this purpose, a discount rate of the following formula is used:

r - a discount rate,

n - number of periods.

Owing to the concept of time value of money used in the above formula it is possible to ensure consistency between incurred expenditures and revenues achieved in subsequent years. Estimation of discount rate value is one of the key elements of investment profitability assessment. A discount rate can be determined on the basis of the following concepts:

- A minimum rate of return at which a project implementation will cause an increase in market value of the company,

- Rate of return on risk-free instruments (e.g. government bonds) increased by a risk premium specific to the country,

- A rate of return that can be achieved by investing in similar projects with a similar level of risk to the analyzed project (the so-called alternative rate of return),

- A rate of inflation increased by a risk premium specific to the country,

- Cost of a company’s capital (Jajuga and Jajuga, 2006: 342).

It is accepted that a value of a discount rate depends on the policies adopted by the company.

*The cost of company’s capital*

In order to finance projects, companies use a variety of funding sources. A company’s management determines how capital structure will look like, while capital owners decide about its cost. The capital owners expect risk and time premiums. If a company uses both forms of recourses: own and foreign, cost of capital is determined as follows:

WACC –Weighted Average Cost of Capital,

w_{w} – share of equity,

k_{w} – cost of equity,

w_{d }– share of foreign capital,

k_{d} – cost of foreign capital,

T – income tax rate from company’s profits.

As it appears from the above formula it is necessary to take into account income tax rate while calculating WACC. This is due to the fact that a company being financed by a bank loan is forced to pay interests on its liabilities to the bank (Jajuga and Jajuga, 2006: 337, 338). This results in a decreased income, which is taxable. In addition a company that finances itself with equity might be at risk of loss of own resources. In case of using foreign capital a risk of capital loss is transferred to a lender. The biggest advantage of equity is its lower cost in comparison with foreign capital (Duliniec, 2007: 88).

*Cash flows*

Another key element of profitability assessment is valuation of cash flows for subsequent years. They cover both construction and operation periods of a facility that resulted from an investment. Amount of cash flows for a single period is calculated as follows:

**Table 1.**

**Scheme of cash flows determination**

*Source: own study.*

The starting point for cash flows estimation for each period is the net profit achieved by the implementation of the investment project. This point is to be corrected by an amount of amortization. This is due to the fact that amortization is a reporting period cost but the company does not bear expenses (non-cash expenses) in this respect.

Change in liabilities balance should be understood as revenues that a company obtained as a result of incurring credit or these expenses that are associated with repayment of liabilities to the lender. It should be noted that only capital part of a credit installment decreases cash flow. An interest part is taken into account at the determination of net profit.

During operation of a facility, expenses related to modernization or replacement of machinery are incurred. These expenses are classified as investments in current assets and reduce value of cash flows during the period. The mentioned assets components can be liquidized. Then such a transaction constitutes additional income.

Investments in current assets should be understood as expenses associated with an increase in inventories or receivables. As in the case of fixed assets, sale of current assets results in additional revenue (Rutkowski, 2003: 210-212).

*The Net Present Value*

Net Present Value, NPV is a sum of discounted positive cash flows generated in subsequent years reduced by discounted expenditures related to a project implementation. NPV is calculated by the following formula:

I_{o }– capital expenditures,

CF_{n }– cash flow,

d_{n} – a discount rate.

The above equation assumes that the expenditures are incurred only in year 0. However, many projects are characterized by a negative cash flow in subsequent periods. Thus, more universal is the following formula, which assumes that negative cash flows can occur not only during 0 period.

CFt – Cash flow (cash flow in the year t, positive or negative).

Since the NPV is an amount by which a value of a company will increase as a result of an adoption of project implementation, thus interpretation of the NPV is as follows:

- NPV > 0, a project should be implemented,

- NPV < 0, a project should be rejected,

- NPV = 0, a decision on a project implementation should be based on other factors not included in the analysis (CFA Institute, 2012: 10, 11).

In addition, the NPV is a criterion particularly useful in projects analysis of unconventional cash flows.

*Profitability Index*

Profitability Index is a quotient of discounted positive cash flows and capital expenditures. PI is determined by the following formula:

CIF_{t} – positive cash flow in a period t,

COF_{t} – negative cash flow in a period t.

It may be noted that PI criterion is highly correlated with NPV criterion. Thus, when NPV > 0, a profitability index will take values greater than 1, while NPV < 0, a profitability index will be lower than 1. Interpretation of PI index is as follows:

- PI > 1, a project should be implemented,

- PI < 1, a project should be rejected,

- PI = 1, a decision on implementation of a project should be based on other factors not included in the analysis.

A profitability index criterion is relative and indicates how much revenue one expenditure unit will generate (CFA Institute, 2012: 17).

*Internal rate of return*

Internal Rate of Return (IRR) is one of the most frequently used methods in an analysis of both investment projects, as well as securities. For investments characterized by conventional cash flows (capital expenditures are incurred in initial stages ,however, in subsequent years only positive cash flows are achieved), IRR is a value of discount rate, where current value of positive cash flows equals capital expenditures. This relation is described by the formula presented below:

This formula can be transformed as follows:

This form of the above formula resembles equation that allows to calculate a value of NPV. Thus, IRR determines maximum value of a discount rate for which the project’s NPV equals 0. The investment decisions based on NPV criterion are taken as follows:

- IRR > r, means that an investment project should be adopted for implementation because at a given cost of capital it will generate positive NPV,

- IRR = r, means that a project has no impact on increase of company’s value, therefore whether the project should be implemented or not other factors not included in the analysis decide,

- IRR < 0, a project should be rejected.

It is assumed that in calculating IRR all received income will be reinvested at the same rate of interest as in discounting. This is an assumption virtually unheard of in a market economy. This is due to the fact that many entities on the market offer a lot of different possibilities, both in acquisition and investment of capital.

In addition, there are some limitations when using the IRR method for assessment of investment profitability. There are two cases when the IRR does not answer the question of whether an implementation of a project is justified.

**Fig.6. NPV curve for a project with multiple IRR**

*Source: own study based on CFA Institute, Corporate Finance and Portfolio Management, Pearson 2012: 24, 25.*

In conventional projects where positive cash flows occur in later periods than capital expenditures a problem of multiple IRR does not exist. In the example presented above (Fig. 6) such a situation can occur because capital expenditures are also in subsequent years. This is the case when IRR equation is a polynomial. Thus, it is possible that as much value of IRR can be achieved as many times cash flows will change their sign. In addition, it is possible that an analyzed project willnot have an internal rate of return (Fig. 7).

**Fig. 7. NPV curve for a project without IRR**

*Source: own study based on CFA Institute, Corporate Finance and Portfolio Management, Pearson 2012: 24, 25.*

These considerations relate to problems with determination of IRR. Fortunately, most of investments has only one value of IRR (CFA Institute, 2012: 11-13, 23-26).

*The selection of mutually exclusive projects*

For an individual project with conventional cash flows NPV and IRR indications are identical. If NPV indicates profitability of a project, so does IRR (CFA Institute, 2012: 19-23). Some problems arise when two projects are analyzed but only one of which may be adopted for implementation (the so-called projects mutually exclusive). However, there is a possibility where two criteria (NPV and IRR) are incompatible. At that point a conflict of selection arises and it means that NPV criterion indicates another project as more cost-effective than IRR method (Fig. 8). This situation can occur when:

- Projects differ in the amount of capital expenditure (i.e. project scale),

- Projects differ in distribution of cash flows over time (Brigham and Gapenski, 2000: 309-312).

**Fig. 8. Conflict of choice of investment projects**

*Source: own study based on CFA Institute, Corporate Finance and Portfolio Management, Pearson 2012: 22.*

NPV curves of both analyzed projects intersect at point C, which corresponds to value of IRR_{c}. IRR_{c }is an internal rate of hypothetical return of a project, called „incremental" project whose cash flows constitute a difference between project A and B cash flows. Thus, the IRR_{c }is a discount rate for which NPV of two analyzed projects are equal. If there is IRR_{c }value, a choice of optimal investment project shall be as follows:

- If a capital cost of both projects is lower than predetermined value of IRR_{c} then a project whose NPV is greater should be adopted for an implementation;

- If, however, a cost of capital is higher than a predetermined value IRR_{c} a project whose internal rate of return is higher should be implemented.

Problems also arise during analysis of two mutually exclusive projects with different lifetime. NPV indications in case of two mutually exclusive projects may prove to be incorrect. There are two methods to make optimal investment decision:

- Replacement Chain Method - consists of leveling lifetimes of analyzed projects (when lifetime of a project has ended, it is assumed that this project will be implemented again),

- Equivalent Annual Annuity (EAA) - consists of determination of equivalent annual value (so-called annuity in arrears) NPV.

In both cases mentioned above a project characterized by higher calculated values will be adopted for the implementation (Jajuga and Jajuga, 2006: 350, 351, 354)

*The safety margin*

The safety margin is a positive deviation between maximum discount rate value (IRR), at which an investment project will not generate losses, and a value of discount rate adopted for calculation.

Safety margin signifies financial security of a project. It is a very useful tool in case of financing investments by foreign capital whose interest rate is variable over time

(i.e. it depends on WIBOR), because it allows to estimate to what maximum extend an interest rate of incurred liability can increase not to cause a simultaneous decrease in value of a project (Rutkowski, 2003: 219).

*Modified internal rate of return*

Modified Internal Rate of Return (MIRR) is a modification of IRR method described above. The assumption on the level of reinvestment of income has changed. MIRR criterion assumes that positive cash flows can be reinvested according to offered market opportunities. MIRR is calculated by the following formula:

CIF_{t} - positive cash flow in period t reinvested by any interest rate,

COF_{t} - negative cash flow in period t.

MIRR is a limit value of a discount rate. At that value equalization of incurred capital expenditures with positive discounted cash flows occurs. They are reinvested according to opportunities offered by the market. MIRR criterion cannot be used to assess profitability of investments of non-conventional cash flows (similarly to IRR) (Rutkowski, 2003: 235, 236).

*Discounted payback period*

Discounted payback period determines a period after which there will be a balance of capital expenditures value with a sum of discounted cash flows achieved in subsequent years. DPP is a criterion which uses discounted cash flows just like NPV criterion. This means that if NPV of a project is negative it is probable that DPP does not exist because expenses will never be covered by revenues from operation of investment. It should be noted that the DPP method does not take into account cash flows that occur after achievement of a balance between income and expenditure. This approach makes the DPP not to be a good method of evaluation effectiveness of the whole project. In addition, there is a possibility that an investment project is characterized by a negative NPV, however during life of an investment it generates positive discounted cash flows which cause calculation of DPP value possible (CFA Institute, 2012: 17).

*Analysis of net cash flows in subsequent years*

In order to estimate profitability of wind farm construction in Poland calculated cash flows for period 2013-2039 were used. The analysis was carried out for a case of wind farm that consist of 15 Vestas V-90 wind turbines located over an area of about 345 acres.

The years 2013-2015 is a period when significant capital expenditures will be incurred. First revenues from electricity sales will appear in January 2015. The analysis has been prepared for the years up to 2039 due to the fact that the lifetime of a wind turbine is 25 years. At the end of this period a thorough modernization of the wind park will be necessary.

**Table 2.**

**Cash flows in 2013-2018**

*Source: own study.*

**Table 3.**

**Cash flows in ****2019-2025**

*Source: own study.*

**Table 4.**

**Cash flows in ****2026-2032**

*Source: own study.*

**Table 5.**

**Cash flows in ****2033-2039**

*Source: own study.*

The years 2013 and 2014 due to ongoing construction work will be completed with a loss. First revenues will appear in January of 2015. Value of earned income in the first year of wind farms operation will amount to 39.5 million PLN. In subsequent years, an increase of income due to the indexation of electricity prices will appear. Income from whole time operation of the wind park will be 1 157 million PLN.

Operating costs including depreciation write off and offshore/external financing costs will amount to 30.23 million PLN in the first year of use. Repayments of loan instalments and depreciation write off will end in 2029. Total costs associated with pursuit of business activity in the period of 2015-2039 will amount to 614.85 million PLN. Temporary problems with financial liquidity may occur for the years 2015 and 2016. This may result in problems with repayment of liabilities. Conditions of "Good Energy Loan" authorize a possibility of suspension of liabilities repayment for a period of 18 months. During this period a recovery of liquidity and resumption of loan repayment will be possible. In addition, there are other tools such as working capital loans, which allow companies to regain financial liquidity. Thus, a temporary lack of liquidity will not adversely affect economic profitability of an investment. In the first year of wind farm operation net profit will reach 0,857 million PLN. In subsequent years, net income will increase to reach 32.5 million PLN in 2039. Net profit developed in the years 2015-2039 will amount to 363.99 million PLN.

A detailed description of the research, basic risk factors, instruments used to eliminate or minimalize these risks and the methods of estimating the impact of risk on the profitability of the venture are described by the authors in the monograph which is due to be published at the end of 2014. This article presents merely the research objectives as well as basic information concerning the profitability of the venture analysed.

**Discussion**

*A few notes to conclu**de*

Although there are many methods to estimate project cost-effectiveness, a decision making related to an investment implementation is a difficult task. The choice of a method to estimate the cost-effectiveness of a project depends on individual preferences of managers. However, bearing in mind a paramount importance of investment decisions for the future of a company a decision should be made based on more than one criterion. This is due to the fact that each and every method analyzes a project from a different perspective thus providing a fuller picture of an investment.

Theoretically, NPV is considered to be the best. This criterion should be applied especially when analyzing projects of non-conventional cash flows and mutually exclusive (Jajuga and Jajuga, 2006: 354). It should be noted that a condition for accurate estimates is an adequate determination of cash flows, a discount rate and duration of an investment (Rutkowski, 2003: 255).

Due to the fact that an investment in a wind farm construction is characterized with a long duration of profitability assessment, the authors recommend discount methods and concept of weighted average cost of capital to determine a discount rate. A discounted rate estimated according to this method for the analyzed project (a wind farm construction located in the north-eastern part of Poland) equals 9.931%. This value includes interest rate amount of a loan (WIBOR 3M + Margin: 9.597%) and a value of Polish Energy Partners equity rate of return (18,56%). Net present value (NPV) of the analyzed project is 78.8 million, while the profitability index (PI) 3.06. The internal rate of return (IRR) and modified internal rate of return (MIRR) the authors estimated at the level of 22.439% and 11.836% respectively. Thus, all of indicators used to assess profitability of an investment indicate that the studied project is viable.

**References:**

- Brigham E. F., Gapenski L.C., Financial management, Polish Economic Publishing House, Warsaw 2000: 309-312.
- Ciżkowicz P., Gabryś A., Baj K., Bawół M., The impact of wind energy on economic growth in Poland, Ernst & Young, March 2012: 48, 49.
- CFA Institute, Corporate Finance and Portfolio Management, Pearson 2012: 5, 6, 10, 11-13, 17, 19-26.
- Duliniec A., Financing companies, Polish Economic Publishing House, Warsaw 2007: 88.
- The Foundation for Sustainable Energy - Advisory Group SMDI 2012. Analysisof the required level of support for offshore wind farms in Poland until 2025. Warsaw: 30.
- Gajewski J., Szefler K., Hac B., Zaucha J., Possible use of Polish marine areas for wind energy development, Maritime Institute in Gdańsk, Gdańsk 2013: 4.
- Jajuga K., Jajuga T., Investments, Scientific Publishing PWN, Warsaw 2006: 9, 350, 351, 354.
- Ministry of Economy, Report setting out targets for the share of electricity produced from renewable energy sources located on Polish territory, in domestic electricity consumption 2010-2019, Warsaw 2011: 5.
- Rutkowski A., Financial management, Polish Economic Publishing House, Warsaw 2003: 210-212, 219, 235, 236, 255.
- Statistical Yearbook of the Republic of Poland 2012, Warsaw 2012: 651.
- The Quarterly Journal of Economics 79(4)/1965: 509-536, doi: 10.2307/1880650.
- Wind from the East, Emerging European markets wind energy, European Wind Energy Association, February 2013: 10.
- Wind in Power 2012 European statistics. 2013. The European Wind Energy Association, February: 10.

Комментарии: 4

Dear Marianna Balasanian, kobyakova, Tatiana Suvorova,
Thank you very much for the constructive comments.
Best regards
Grażyna Wójcik

Уважаемые коллеги. Спасибо за интересный доклад. Чувствуется, что проведена большая работа и имеются важные, научно обоснованные результаты. С уважением, Марианна Б.

Уважаемые Гражина и Якуб, тема актуальна, интересна и значима! Всего доброго! Удачи! С ув. Ирина Кобякова

Dear Grażyna Wójcik and Jakub Woźniak, your paper is very informative, but you must have been mistaken while choosing the event to participate in. Tatiana.

## Grażyna Paulina Wójcik

11 / 11 / 2014 - 22:04## Баласанян Марианна Альбертовна

10 / 13 / 2014 - 17:48## Кобякова Ирина

10 / 12 / 2014 - 16:41## Суворова Татьяна Николаевна

10 / 11 / 2014 - 18:17