Introduction
    The main stated goal of the UNFCCC process in the power engineering is to reduce greenhouse gas emissions to the environment by phasing out the use of fossil fuel energy systems (FFS). Further, it is called the Main Goal. The essence of the UNFCCC process is to replace FFSs with Renewable Energy Sources (RES).
    It is obvious that for the manufacture of renewable energy structures, their delivery to the place of use, installation, commissioning and maintenance, a certain amount of energy, materials and labor of people are always expended. All of these works are accompanied by environmental impacts at the places of their implementation. Often, the above work is performed long before the start of the use of RESs and several thousand kilometers from the place of their use. In addition, there is no accurate and uniform end-to-end accounting of labor costs of people, energy, materials and harmful environmental impacts when performing these works.
    This time lag, remoteness and lack of end-to-end accounting break the causal link between global environmental change and the use of RESs regardless of the total values ​​of the above costs and impacts due to the breakdown of this causal relationship. The illusion of the absolute “environmental friendly” of RESs arose due to the breaking of this causal relationship and the absence of tangible environmental impacts at the places of their use. Gradually, this illusion grew into a persistent misconception about the absolute “environmental friendly” of RESs due to the media and the involvement of many enthusiasts in the struggle to preserve the environment.
     However, the published research results have clearly shown that RESs may be both "environmentally friendly" and "environmentally dirty" – see https://www.linkedin.com/pulse/choosing-best-systems-based-renewable-energy-process-valery-matveev-1f and https://www.linkedin.com/pulse/calculation-energy-transition-parameters-when-choosing-valery-matveev. Thus, it was proved that the postulate of the absolute "environmental friendly" of RESs is a misconception.
    The studies mentioned above have shown the decisive value of the energy efficiency of RESs to accelerate the UNFCCC process when replacing FFS with ones. They allowed us to calculate that the lack of control of RES energy efficiency by UNFCCC reduces about 2 times the environmental effect of investments. Consequently, the mentioned studies reinforced the importance of energy efficiency of RESs, which was already repeatedly emphasized in the UNFCCC documents (see, for example, UNFCCC/SBSTA/2007/INF.3, ADP.2013.13.InformalSummary, UNFCCC/TP/2014/3, UNFCCC/TP/2015/4 and UNFCCC/TP/2016/5).
    Studies have also shown that the documents of the UNFCCC process do not meet its Main Goal. The reason for this discrepancy is the lack of a description of the criterion for evaluating the energy efficiency of RESs, methods for its calculation; its minimum permitted value, methods for its control, recommendations for providing, etc. This gives the right to replace FFSs with any RESs, regardless of their energy efficiency. Thanks to this, the entire UNFCCC process is reduced to the banal replacement of all FFSs with RESs. In other words, the entire UNFCCC process consists in the global replacement the one equipment with another, which is a priori recognized as “environmentally friendly”.
    Accounting turned out to be the only type of end-to-end accounting that accompanies all types of work related to the use of RESs. Under these conditions, the only criterion for choosing RES for the UNFCCC process is economic efficiency. The UNFCCC process has thus evolved from a global environmental project into a global economic project under an environmental pretext. Thanks to the transformation described above, the energy efficiency of RESs was left without proper control of the UNFCCC, and the main attention was paid to the volumes of investments.
    The peculiarity of accounting is the lack of an exact relationship the amount of money and the values ​​of the above-mentioned labor costs of people, energy, materials and harmful environmental effects that coincide with them in time and place. In particular, the increase energy volumes for the implementation of the above works may coincide to a decrease the cost of money for them. Therefore, it is unreasonable and dangerous for the global ecology to choose RESs on base the economic efficiency for replacing FFS in the UNFCCC process.
    The purpose of this article is to draw attention to:
· The obvious importance of the energy efficiency of RESs for the UNFCCC process, as indicated in its documents;
· The absence in UNFCCC documents of the criterion of energy efficiency, the technology of its calculation, the technology of its application, the maximum permitted values, etc;
· The fundamental possibility of the existence of "environmentally dirty" RESs;
· Great danger to the global ecology of the massive use of "environmentally dirty" RESs due to the delayed manifestation of its result and the high cost to eliminate it;
· The lack of reliable information on the real values ​​of the energy efficiency of RESs used in the UNFCCC process, under its obvious importance;
· A real opportunity to use the RES energy efficiency as a tool to improve the UNFCCC process;
· Relatively low cost of organizing control over the energy efficiency of renewable energy sources with the opportunity to obtain economic and environmental benefits of tens of percent.
    The description of the possible use of energy efficiency of RESs as a tool of the UNFCCC process is given below. It shows the technology for calculating the criterion of energy efficiency, its availability, simplicity, low costs in comparison with the global environmental effect of its use, etc.
What is Energy Efficiency of RES
    Any effectiveness is evaluated by comparing the value of the positive effect to the cost to obtain this effect. Accordingly, the energy efficiency of any RES is estimated by the ratio the amount of energy received from it during its entire operation and the amount of energy expended on it.
    Energy sciences use an efficiency factor (Ef) to evaluate the energy efficiency of RES. It shows what part of the power of the flow of energy from the environment RES converts into usable power. It also shows how much of the total converts into useful energy amount of energy from the environment acting on it (SEn), RES. Ef takes into account all losses in all RES elements. The following are descriptions of Ef of several types of RES, including:
    The efficiency factor of RES with solar panels (Eff) shows how much of the power of the flow of solar energy that has fallen onto the surface of the solar panel is converted into electricity. It takes into account the loss of direct conversion of light energy into electricity, as well as losses in wires, in energy storage, in a converter, etc.
    The efficiency factor of RES with a wind turbine (Efw) shows how much of the power of the air flow acting on the blades of its impeller is converted into electricity. It takes into account losses of direct conversion of wind energy into mechanical energy, mechanical energy into electricity, as well as losses in wires, in energy storage, in a converter, etc.
    The efficiency factor of a RES with a water wheel (Eft) shows how much of the power of the water flow acting on its impeller is converted into electricity. It takes into account losses of the direct conversion of the energy of the water flow into mechanical energy, mechanical energy into electricity, as well as losses in wires, in the energy storage, in the converter, etc.
    The first thing that immediately attracts attention when familiarizing yourself with RES projects for the UNFCCC process is their gigantic size with relatively low power – see Fig. 1.

    Windmills with towers more than 300 meters high and blades more than 100 meters long, kilometer-sized solar panels and huge platforms at sea that weigh hundreds and thousands of tons are the RES prototypes for the UNFCCC process. Obviously, for the manufacture of every gram of their design, energy was expended! However, the assessment of their energy efficiency remained in the background, as if they were still made in the garage. Therefore, the appearance of the prototypes raises several practical and theoretical issues related to the achievement of the Main Goal, including:
    1 question: "Will there be enough energy is generated by this RES to the producing it itself?"
    2 question: “Which RES is able to quickly compensate for the energy spent on its creation from several possible for use?”
    3 question: "How to evaluate the energy cost efficiency of manufacturing RES?»
    4 question: “How to evaluate the energy efficiency of converting energy received from the environment into usable energy?”
    The above Ef does not give an answer to these questions because it does not take into account the energy expenditures on RESs it selves.
    The first of the efficiency criteria that we developed which we called the self-reproduction ratio (Ksr) of RES gives the answers to questions 1 and 2. The second of the efficiency criteria that we developed, which we called the energy efficiency ratio (Ke) of RES, is the answer to 3rd question. The third criterion of efficiency, which we called the total energy efficiency ratio (Kte) of RES, is the answer to 4th question.
    The self-reproduction ratio of RES
     Self-reproduction of RES is its ability to produce energy in an amount sufficient to product a replacement for it itself. This ability is calculated through the self-reproduction ratio (Ksr). We calculate its value as the ratio of the amount of energy generated by RES during the entire service life to the amount of energy spent on its creation and functioning during the same period. When calculating the energy spent, the energy spent on the manufacture of equipment, materials, transportation and construction works, maintenance, repair, commissioning, routine maintenance, and also the energy of the fuel, including the energy spent on its transportation. To calculate the value of Ksr, the formula is applied:
    Ksr = SREn / SPEn - formula 1
    Symbols in the formula 1:
    SREn – the total amount of energy generated by RES during its service life;
    SPEn – the total amount of energy spent on the creation and operation of this RES. The value of SPEn is calculated by the formula:
    SPEn = SPEn1 + SPEn2 + SPEn3 + … + SPEnj + … + SPEnJ - formula 2
    Symbols in the formula 2:
    SPEn1, SPEn2, SPEn3, …, SPEnj, …, SPEnJ – the total amount of energy spent on the creation and operation of this RES, including: the energy spent on the manufacture of equipment, materials, transportation and construction works, maintenance, repair, commissioning, routine maintenance, as well as fuel energy, including energy, spent on its transportation;
     j – work type symbols: j = 1, 2, 3, …, j, …, J.
The value of the self-reproduction ratio Ksr in practice varies from approximately 0.4 to 10. It is convenient to use in the UNFCCC process to compare the degree of environmental friendliness of the RES in the process of choosing it to replace FFS, for example:
If the Ksr value of a real RES is less than 1 (i.e., Ksr <1), then for the entire service life up to its utilization, it produces less energy than is expended to it (i.e., SREn < SPEn). Obviously, taking such a RES for an UNFCCC process is unwise because it can never replace FFS. And the combined use of FFS and such RES will lead to more intense environmental degradation than when using only FFS.
If the Ksr value of a real RES is 1 (i.e., Ksr = 1), then over the entire service life up to its utilization, it produces as much energy as it was spent to it (i.e., SREn = SPEn). Obviously, taking such a RES for an UNFCCC process is unwise too because it can never replace FFS. And the combined use of FFS and such RES will lead to more intense environmental degradation than when using only FFS too.
    If the Ksr value of a real RES is greater than 1 (i.e., Ksr > 1), then over the entire service life up to its utilization, it produces more energy than is expended to it (i.e., SREn > SPEn). Obviously, such a RES can to replace FFS. However, if the value of Ksr is not much more than 1, for example, equal to 1.001 (i.e., Ksr = 1.001), then the entire Earth's surface will need to be used to install RES to globally replace all FFS. Obviously, such a replacement is energetically inefficient.
    Consequently, there is a certain limit to Ksr value, less than which the use of RESs in the UNFCCC process becomes energetically ineffective. This limit is conditionally designated Ksrmin. A preliminary estimate shows that Ksrmin may be equal to 2 (i.e., Ksrmin = 2).
    Based on the foregoing, the following classification of RES by energy efficiency for the UNFCCC process is proposed:
RESs that have Ksr ≤ 1.1 are “environmentally dirty”;
RESs that have 1.1 < Ksr ≤ 2 are energy inefficient;
RESs that have Ksr > 2 are energy efficient, that is, "environmentally friendly."
The energy efficiency ratio of RES
    Energy efficiency of RES is its ability to rationally use the energy spent on its creation and functioning. This ability is determined through the value of the energy efficiency ratio (Ke). We define it as the quotient of dividing the difference between the amount of energy generated by RES during its service life and the amount of energy spent on the creation and functioning of this RES to the amount of energy spent on the creation and functioning of this RES. Thus, the calculation of Ke is based on the same values ​​that were used above in formula 1 when calculating the value of Ksr:
    Ke = (SREn - SPEn) / SPEn - formula 3
    Symbols in the formula 3 - see above.
    A strict mathematical relation for the quantities Ke and Ksr is represented by the formula:
    Ke = Ksr - 1 - formula 4.
    Conventions in the formula 4 - see above.
    The value of Ke in practice varies from approximately -0.6 to 9. It is convenient to use in the UNFCCC process to compare the degree of environmental friendliness of the RES in the process of choosing it to replace FFS too, for example:
    RESs that have Ke ≤ 0.1 are “environmentally dirty”;
    RESs that have 0.1 < Ke ≤ 1 are energy inefficient;
    RESs that have Ke > 1 are energy efficient, that is, "environmentally friendly."
The total energy efficiency ratio of RES
    The total energy efficiency of RES is its ability to efficiently convert the energy received from the environment into usable energy in combination with the rational use of the energy spent on its creation and functioning. This ability is calculated through the value of the total energy efficiency ratio (Kte). We calculate it as the ratio of SREn of the RES under consideration to the sum of its SPEn and SEn (see all conventions above) by the formula:
    Kte = SREn / (SPEn + SEn) - formula 5
    Conventions in the formula 5 - see above.
    The value of the total energy efficiency ratio Kte in practice varies from approximately 0.1 to 0.22. It is convenient to use to compare the degree of technical excellence of RES in the process of their design.
    The use of Kte may provide a more accurate choice of the most energy-efficient renewable energy compared with the use of Kcr or Ke. However, its technical application requires the installation of additional equipment to automatically registration the energy flow from the environment affecting RESs. This may create additional difficulties for their economic justification due to lack of sufficient information.
    In other words, using Kcr and Ke as criteria for choosing the best RES when replacing FFS in the UNFCCC process will reduce the total greenhouse gas emissions by tens of percent. And the rationale for their use is extremely simple and obvious. It contains only three arithmetic operations and one logical function, does not require additional equipment, and is already formally stated in the UNFCCC documents. Applying Kte as a criterion will add a few more percentages to the effect of Kcr and Ke, is a little harder to justify, and take more time to adopt and implement. Therefore, the use of Kcr and Ke as energy efficiency criteria for the UNFCCC process is considered below.
    Reducing the duration of the UNFCCC process by increasing the energy efficiency of RES
    The duration of the period for replacing all FFS with RES should be minimal for a given volume of commissioning of RES capacities and other conditions being equal. This will minimize the duration of the harmful impacts of FFS to the environment until they are completely replaced. The formulas for calculating the duration reduction of the replacement period for all FFSs with RESs due to their increased energy efficiency are below:
    NT = Kcrx *(Kcr – 1) / Kcr *(Kcrx – 1) - formula 6
    Symbols in formula 6:
    NT – coefficient for reducing the duration of the replacement period of all FFS with RES due increasing their energy efficiency;
    Kcr – the value of the RES self-replication ratio before increasing energy efficiency;
    Kcrx – the value of the RES self-replication ratio after increasing energy efficiency;
    NT = Ke *(Kex + 1) / Keх *(Ke + 1) - formula 7
    Symbols in formula 7:
    Ke – the value of the RES energy efficiency ratio before increasing energy efficiency;
    Kex – the value of the RES energy efficiency ratio after increasing energy efficiency;
    Tchx = NT * Tch - formula 8
    Symbols in formula 8:
    Tchx – duration of the FFS replacement period after increasing energy efficiency;
    Tch – duration of the FFS replacement period before increasing energy efficiency;     
    the rest – see above.
    The dependence of NT on the combination of Kcr and Kcrx is shown in Fig. 2. The area of ​​energy inefficient RES (see above) is highlighted in red in Fig. 2. The area of ​​energy efficient RES is highlighted in green in Fig. 2.
    Calculations show that for some combinations of Kcr and Kcrx, the NT value may be very small. For example, with Kcr = 1.01 and Kcrx = 10, the value NT = 0.011. Consequently, the NT duration for these variants differs by 1 / NT = 1 / 0.011 = 90.9 times! The mistake may be such scale at present when choosing RES without using energy efficiency, because it is impossible to calculate the value of the energy efficiency criterion according to the rules of the UNFCCC process.
    An example of calculating the duration decrease of the FFS replacement period due increasing energy efficiency is below.
    EXAMPLE 1
    Initial data:
    Tch = 5 years – the duration of the period of replacing FFSs with RESs until energy efficiency increases;
    Kcr = 2.65 – the value of the self-reproduction ratio of RESs before increasing energy efficiency;
    Kcrx = 10 – the value of the self-reproduction ratio of RESs after increasing energy efficiency;
    Ke = 1.65 – the value of the energy efficiency ratio of RESs before increasing energy efficiency;
    Kex = 9 – the value of the energy efficiency ratio of RESs after increasing energy efficiency.
    The task:
    Calculate the duration of replacing FFSs with RESs after increasing energy efficiency.
    The solution:
    1. Calculation the coefficient value of reducing the duration of the replacement period of FFSs with RESs due to the increase in their energy efficiency.
    NT = Kcrx *(Kcr – 1) / Kcr *(Kcrx – 1) = 10 *(2.65 – 1) / 2.65 *(10 – 1) = 0.692
    NT = Ke *(Kex + 1) / Keх *(Ke + 1) = 1.65 *(9 + 1) / 9 *(1.65 + 1) = 0.692
    2. Calculation of the duration of the period for replacing FFSs with RESs after increasing energy efficiency.
    Tchx = NT * Tch = 0.692 * 5 = 3.46 years.
    The calculation has showed that the use of either Kcr or Ke does not affect the duration of the UNFCCC process. Therefore, only the application of Kcr is briefly considered below in the technology, which we called the “Noologistic Choosing a Renewable Energy” (NCRE). The word “Noologistic” in the NCRE name comes from the ancient Greek words νόος - noo (reasonable) and logitsich - logistics (the art of counting). Learn more about NCRE – see https://www.linkedin.com/pulse/calculation-energy-transition-parameters-when-choosing-valery-matveev.
Technology for choosing the best RES for the UNFCCC process
    The essence of NCRE is to choose RES of maximum energy efficiency. It consists in performing operations, the scheme of which is presented in Fig. 3. NCRE operations are described below.