How is efficiency calculated? The concept of efficiency: definition, formula and application in physics
« Physics - 10th grade"
What is a thermodynamic system and what parameters characterize its state.
State the first and second laws of thermodynamics.
It was the creation of the theory of heat engines that led to the formulation of the second law of thermodynamics.
Internal energy reserves in earth's crust and oceans can be considered practically unlimited. But for a solution practical problems Having energy reserves is not enough. It is also necessary to be able to use energy to set in motion machine tools in factories and factories, vehicles, tractors and other machines, and to rotate the rotors of generators electric current etc. Humanity needs engines - devices capable of doing work. Most of the engines on Earth are heat engines.
Heat engines- these are devices that convert the internal energy of fuel into mechanical work.
Operating principle of heat engines.
In order for an engine to do work, there needs to be a pressure difference on both sides of the engine piston or turbine blades. In all heat engines, this pressure difference is achieved by increasing the temperature working fluid(gas) by hundreds or thousands of degrees compared to the temperature environment. This temperature increase occurs when fuel burns.
One of the main parts of the engine is a gas-filled vessel with a movable piston. The working fluid of all heat engines is gas, which does work during expansion. Let us denote the initial temperature of the working fluid (gas) by T 1 . This temperature in steam turbines or machines is achieved by the steam in the steam boiler. In engines internal combustion and gas turbines, the temperature rise occurs when fuel burns inside the engine itself. Temperature T 1 is called heater temperature.
The role of the refrigerator.
As work is performed, the gas loses energy and inevitably cools to a certain temperature T2, which is usually slightly higher than the ambient temperature. They call her refrigerator temperature. The refrigerator is the atmosphere or special devices for cooling and condensing waste steam - capacitors. IN the latter case The refrigerator temperature may be slightly lower than the ambient temperature.
Thus, in an engine, the working fluid during expansion cannot give up all its internal energy to do work. Some of the heat is inevitably transferred to the refrigerator (atmosphere) along with waste steam or exhaust gases from internal combustion engines and gas turbines.
This part of the internal energy of the fuel is lost. A heat engine performs work due to the internal energy of the working fluid. Moreover, in this process, heat is transferred from hotter bodies (heater) to colder ones (refrigerator). Schematic diagram heat engine shown in Figure 13.13.
The working fluid of the engine receives an amount of heat Q 1 from the heater during fuel combustion, does work A" and transfers the amount of heat to the refrigerator Q 2< Q 1 .
In order for the engine to operate continuously, it is necessary to return the working fluid to its initial state, at which the temperature of the working fluid is equal to T 1. It follows that the engine operates according to periodically repeating closed processes, or, as they say, in a cycle.
Cycle is a series of processes as a result of which the system returns to its initial state.
Coefficient of performance (efficiency) of a heat engine.
Impossibility complete transformation The internal energy of gas in the operation of heat engines is due to the irreversibility of processes in nature. If heat could return spontaneously from the refrigerator to the heater, then the internal energy could be completely converted into useful work by any heat engine. The second law of thermodynamics can be stated as follows:
Second law of thermodynamics:
It is impossible to create a perpetual motion machine of the second kind, which would completely convert heat into mechanical work.
According to the law of conservation of energy, the work done by the engine is equal to:
A" = Q 1 - |Q 2 |, (13.15)
where Q 1 is the amount of heat received from the heater, and Q2 is the amount of heat given to the refrigerator.
The coefficient of performance (efficiency) of a heat engine is the ratio of the work A "performed by the engine to the amount of heat received from the heater:
Since all engines transfer some amount of heat to the refrigerator, then η< 1.
Maximum efficiency value of heat engines.
The laws of thermodynamics allow us to calculate the maximum possible Thermal efficiency an engine operating with a heater having a temperature T 1 and a refrigerator with a temperature T 2 , and also determine ways to increase it.
For the first time, the maximum possible efficiency of a heat engine was calculated by the French engineer and scientist Sadi Carnot (1796-1832) in his work “Reflections on the driving force of fire and on machines capable of developing this force” (1824).
Carnot came up with an ideal heat engine with ideal gas as a working fluid. An ideal Carnot heat engine operates on a cycle consisting of two isotherms and two adiabats, and these processes are considered reversible (Fig. 13.14). First, a vessel with gas is brought into contact with the heater, the gas expands isothermally, doing positive work, at temperature T 1, and it receives an amount of heat Q 1.
Then the vessel is thermally insulated, the gas continues to expand adiabatically, while its temperature drops to the temperature of the refrigerator T 2. After this, the gas is brought into contact with the refrigerator; during isothermal compression, it gives the amount of heat Q 2 to the refrigerator, compressing to a volume V 4< V 1 . Затем сосуд снова теплоизолируют, газ сжимается адиабатно до объёма V 1 и возвращается в первоначальное состояние. Для КПД этой машины было получено следующее выражение:
As follows from formula (13.17), the efficiency of a Carnot machine is directly proportional to the difference in the absolute temperatures of the heater and refrigerator.
The main significance of this formula is that it indicates the way to increase efficiency, for this it is necessary to increase the temperature of the heater or lower the temperature of the refrigerator.
Any real heat engine operating with a heater at temperature T1 and a refrigerator at temperature T2 cannot have an efficiency exceeding that of an ideal heat engine: 
The processes that make up the cycle of a real heat engine are not reversible.
Formula (13.17) gives the theoretical limit for maximum value Efficiency of heat engines. It shows that a heat engine is more efficient, the greater the temperature difference between the heater and refrigerator.
Only at a refrigerator temperature equal to absolute zero does η = 1. In addition, it has been proven that the efficiency calculated using formula (13.17) does not depend on the working substance.
But the temperature of the refrigerator, whose role is usually played by the atmosphere, practically cannot be lower than the ambient air temperature. You can increase the heater temperature. However, any material ( solid) has limited heat resistance or heat resistance. When heated, it gradually loses its elastic properties, and when sufficiently high temperature melts.
Now the main efforts of engineers are aimed at increasing the efficiency of engines by reducing the friction of their parts, fuel losses due to incomplete combustion, etc.
For a steam turbine, the initial and final steam temperatures are approximately as follows: T 1 - 800 K and T 2 - 300 K. At these temperatures, the maximum efficiency value is 62% (note that efficiency is usually measured as a percentage). The actual efficiency value due to various types of energy losses is approximately 40%. The maximum efficiency - about 44% - is achieved by Diesel engines.
Environmental protection.
It's hard to imagine modern world without heat engines. They are the ones who provide us comfortable life. Heat engines drive vehicles. About 80% of electricity, despite the presence of nuclear power plants, is generated using thermal engines.
However, when operating heat engines, inevitable environmental pollution occurs. This is a contradiction: on the one hand, humanity needs more and more energy every year, the main part of which is obtained through the combustion of fuel, on the other hand, combustion processes are inevitably accompanied by environmental pollution.
When fuel burns, the oxygen content in the atmosphere decreases. In addition, the combustion products themselves form chemical compounds, harmful to living organisms. Pollution occurs not only on the ground, but also in the air, since any airplane flight is accompanied by emissions of harmful impurities into the atmosphere.
One of the consequences of engine operation is the formation carbon dioxide, which absorbs infrared radiation surface of the Earth, which leads to an increase in atmospheric temperature. This is the so-called greenhouse effect. Measurements show that the atmospheric temperature rises by 0.05 °C per year. Such a continuous increase in temperature can cause ice to melt, which, in turn, will lead to changes in water levels in the oceans, i.e., to the flooding of continents.
Let's note one more negative point when using heat engines. So, sometimes water from rivers and lakes is used to cool engines. The heated water is then returned back. An increase in temperature in water bodies disrupts the natural balance; this phenomenon is called thermal pollution.
To protect the environment, various cleaning filters are widely used to prevent emissions into the atmosphere. harmful substances, engine designs are being improved. There is a continuous improvement of fuel that produces less harmful substances during combustion, as well as the technology of its combustion. Alternative energy sources using wind are being actively developed, solar radiation, nuclear energy. Electric and solar powered vehicles are already being produced.
Modern realities require the widespread use of heat engines. Numerous attempts to replace them with electric motors have so far failed. Problems associated with energy storage in autonomous systems, are resolved with great difficulty.
The problems of manufacturing technology for electric power batteries, taking into account their long-term use, are still relevant. The speed characteristics of electric vehicles are far from those of cars with internal combustion engines.
The first steps to create hybrid engines can significantly reduce harmful emissions in megacities, solving environmental problems.
A little history
The possibility of converting steam energy into motion energy was known in ancient times. 130 BC: The philosopher Heron of Alexandria presented a steam toy - aeolipile - to the audience. The sphere filled with steam began to rotate under the influence of the jets emanating from it. This prototype of modern steam turbines was not used in those days.
For many years and centuries, the philosopher's developments were considered just a fun toy. In 1629, the Italian D. Branchi created an active turbine. The steam drove a disk equipped with blades.
From that moment on, the rapid development of steam engines began.
Heat engine
The conversion of fuel into the energy of movement of machine parts and mechanisms is used in heat engines.
The main parts of the machines: heater (system for obtaining energy from the outside), working fluid (performs a useful action), refrigerator.
The heater is designed to ensure that the working fluid accumulates a sufficient supply of internal energy to perform useful work. The refrigerator removes excess energy.
The main characteristic of efficiency is called the efficiency of heat engines. This value shows how much of the energy spent on heating is spent on doing useful work. The higher the efficiency, the more profitable work machines, but this value cannot exceed 100%.
Efficiency calculation
Let the heater acquire from the outside energy equal to Q 1 . The working fluid performed work A, while the energy given to the refrigerator amounted to Q 2.
Based on the definition, we calculate the efficiency value:
η= A / Q 1 . Let's take into account that A = Q 1 - Q 2.
Hence, the efficiency of the heat engine, the formula of which is η = (Q 1 - Q 2) / Q 1 = 1 - Q 2 / Q 1, allows us to draw the following conclusions:
- Efficiency cannot exceed 1 (or 100%);
- to maximize this value, it is necessary either to increase the energy received from the heater or to decrease the energy given to the refrigerator;
- increasing the heater energy is achieved by changing the quality of the fuel;
- reducing the energy given to the refrigerator allows you to achieve design features engines.
Ideal heat engine
Is it possible to create an engine whose efficiency would be maximum (ideally equal to 100%)? The French theoretical physicist and talented engineer Sadi Carnot tried to find the answer to this question. In 1824, his theoretical calculations about processes occurring in gases were made public.
The main idea inherent in the ideal machine can be considered to carry out reversible processes with an ideal gas. We start by expanding the gas isothermally at temperature T 1 . The amount of heat required for this is Q 1. Afterwards, the gas expands without heat exchange. Having reached the temperature T 2, the gas compresses isothermally, transferring energy Q 2 to the refrigerator. The gas returns to its original state adiabatically.
The efficiency of an ideal Carnot heat engine, when accurately calculated, is equal to the ratio of the temperature difference between the heating and cooling devices to the temperature of the heater. It looks like this: η=(T 1 - T 2)/ T 1.
The possible efficiency of a heat engine, the formula of which is: η = 1 - T 2 / T 1, depends only on the temperatures of the heater and cooler and cannot be more than 100%.
Moreover, this relationship allows us to prove that the efficiency of heat engines can be equal to unity only when the refrigerator reaches temperatures. As is known, this value is unattainable.
Carnot's theoretical calculations make it possible to determine the maximum efficiency of a heat engine of any design.
The theorem proved by Carnot is as follows. Under no circumstances can an arbitrary heat engine have an efficiency greater than the same efficiency value of an ideal heat engine.
Example of problem solving
Example 1. What is the efficiency of an ideal heat engine if the heater temperature is 800 o C and the refrigerator temperature is 500 o C lower?
T 1 = 800 o C = 1073 K, ∆T = 500 o C = 500 K, η - ?
By definition: η=(T 1 - T 2)/ T 1.
We are not given the temperature of the refrigerator, but ∆T= (T 1 - T 2), hence:
η= ∆T / T 1 = 500 K/1073 K = 0.46.
Answer: Efficiency = 46%.
Example 2. Determine the efficiency of an ideal heat engine if, due to the acquired one kilojoule of heater energy, useful work 650 J. What is the temperature of the heater heater if the cooler temperature is 400 K?
Q 1 = 1 kJ = 1000 J, A = 650 J, T 2 = 400 K, η - ?, T 1 = ?
In this problem we're talking about about a thermal installation, the efficiency of which can be calculated using the formula:
To determine the heater temperature, we use the formula for the efficiency of an ideal heat engine:
η = (T 1 - T 2)/ T 1 = 1 - T 2 / T 1.
After performing mathematical transformations, we get:
T 1 = T 2 /(1- η).
T 1 = T 2 /(1- A / Q 1).
Let's calculate:
η= 650 J/ 1000 J = 0.65.
T 1 = 400 K / (1- 650 J / 1000 J) = 1142.8 K.
Answer: η= 65%, T 1 = 1142.8 K.
Real conditions
The ideal heat engine is designed with ideal processes in mind. Work is performed only in isothermal processes; its value is determined as the area limited by the graph of the Carnot cycle.
In reality, it is impossible to create conditions for the process of changing the state of a gas to occur without accompanying temperature changes. There are no materials that would exclude heat exchange with surrounding objects. The adiabatic process becomes impossible to carry out. In the case of heat exchange, the gas temperature must necessarily change.
The efficiency of heat engines created in real conditions differs significantly from the efficiency of ideal engines. Note that the processes in real engines occur so quickly that the variation in the internal thermal energy of the working substance in the process of changing its volume cannot be compensated by the influx of heat from the heater and transfer to the refrigerator.
Other heat engines
Real engines operate on different cycles:
- Otto cycle: a process with a constant volume changes adiabatically, creating a closed cycle;
- Diesel cycle: isobar, adiabatic, isochore, adiabatic;
- the process occurring at constant pressure is replaced by an adiabatic one, closing the cycle.
Create equilibrium processes in real engines (to bring them closer to ideal ones) under conditions modern technology not possible. The efficiency of heat engines is much lower, even taking into account the same temperature conditions, as in an ideal thermal installation.
But we should not reduce the role of the calculation efficiency formulas since it is precisely this that becomes the starting point in the process of working to increase the efficiency of real engines.
Ways to change efficiency
When comparing ideal and real heat engines, it is worth noting that the temperature of the refrigerator of the latter cannot be any. Usually the atmosphere is considered a refrigerator. The temperature of the atmosphere can only be accepted in approximate calculations. Experience shows that the temperature of the coolant is equal to the temperature of the exhaust gases in the engines, as is the case in internal combustion engines (abbreviated as ICE).
ICE is the most common heat engine in our world. The efficiency of the heat engine in this case depends on the temperature created by the burning fuel. A significant difference between internal combustion engines and steam engines is the merging of the functions of the heater and the working fluid of the device in the air-fuel mixture. As the mixture burns, it creates pressure on the moving parts of the engine.
An increase in the temperature of the working gases is achieved, significantly changing the properties of the fuel. Unfortunately, this cannot be done indefinitely. Any material from which the combustion chamber of an engine is made has its own melting point. The heat resistance of such materials is the main characteristic of the engine, as well as the ability to significantly affect efficiency.
Motor efficiency values
If we consider the temperature of the working steam at the inlet of which is 800 K, and the exhaust gas - 300 K, then the efficiency of this machine is 62%. In reality, this value does not exceed 40%. This decrease occurs due to heat losses when heating the turbine casing.
The highest value of internal combustion does not exceed 44%. Increasing this value is a matter of the near future. Changing the properties of materials and fuel is a problem that is being worked on the best minds humanity.
General provisions
Efficiency is defined as the ratio of useful, or delivered, power P 2 to power consumption P 1:
Modern electric machines have a high efficiency factor (efficiency). Thus, for DC machines with a power of 10 kW, the efficiency is 83 - 87%, with a power of 100 kW - 88 - 93% and with a power of 1000 kW - 92 - 96%. Only small machines have relatively low efficiency; for example, a 10 W DC motor has an efficiency of 30 - 40%.
Electric machine efficiency curve η = f(P 2) first increases rapidly with increasing load, then efficiency reaches its maximum value (usually at a load close to the rated load) and decreases at high loads (Figure 1). The latter is explained by the fact that individual species losses (electrical I a 2 r and additional ones) grow faster than the useful power.
Direct and indirect methods for determining efficiency
Direct method for determining efficiency from experimental values P 1 and P 2 according to formula (1) can give a significant inaccuracy, since, firstly, P 1 and P 2 are close in value and, secondly, their experimental determination is associated with errors. The greatest difficulties and errors are caused by measuring mechanical power.
If, for example, the true power values P 1 = 1000 kW and P 2 = 950 kW can be determined with an accuracy of 2%, then instead of the true value of efficiency.
η = 950/1000 = 0,95
can be obtained
Therefore, GOST 25941-83, “Rotating electrical machines. Methods for determining losses and efficiency,” prescribes for machines with η% ≥ 85% an indirect method for determining efficiency, in which the amount of losses is determined from experimental data p Σ .
Substituting into formula (1) P 2 = P 1 - pΣ , we get
| (3) |
Using the substitution here P 1 = P 2 + pΣ, we get another form of the formula:
 | (4) |
Since it is more convenient and accurate to measure electrical power (for motors P 1 and for generators P 2), then formula (3) is more suitable for engines and formula (4) for generators. Methods for experimental determination of individual losses and the amount of losses pΣ are described in standards for electrical machines and in manuals for testing and researching electrical machines. Even if pΣ is determined with significantly less accuracy than P 1 or P 2, when using formulas (3) and (4) instead of expression (1), significantly more accurate results are obtained.
Conditions for maximum efficiency
Different types of losses depend on the load in different ways. It can generally be assumed that some types of losses remain constant as the load changes, while others are variable. For example, if a DC generator operates with constant speed rotation and constant excitation flux, then mechanical and magnetic losses are also constant. On the contrary, electrical losses in the windings of the armature, additional poles and compensation windings change proportionally I a ², and in brush contacts - proportionally I A. The generator voltage is also approximately constant, and therefore with a certain degree of accuracy P 2 ∼ I A.
Thus, in a general, somewhat idealized case, we can assume that
Where p 0 – constant losses, independent of load; p 1 – value of losses depending on the first degree k ng at rated load; p 2 – value of losses depending on the square k ng, at rated load.
Let's substitute P 2 of (5) and pΣ from (7) into the efficiency formula.
| (8) |
Let us establish at what value k ng efficiency reaches its maximum value, for which we determine the derivative dη/ dk ng according to formula (8) and equate it to zero:
This equation is satisfied when its denominator is equal to infinity, that is, when k ng = ∞. This case is not of interest. Therefore, it is necessary to set the numerator equal to zero. In this case we get
Thus, the efficiency will be maximum at a load at which variable losses k ng ² × p 2, depending on the square of the load, become equal to the constant losses p 0 .
The value of the load factor at maximum efficiency, according to formula (9),
| (10) |
If a machine is designed for a given value η max, then since the losses k ng × p 1 are usually relatively small, we can assume that
p 0 + p 2 ≈ pΣ = const.
Changing the loss ratio p 0 and p 2, the maximum efficiency can be achieved at different loads. If the machine operates mostly at loads close to the rated load, then it is advantageous that the value k ng [see formula (10)] was close to unity. If the machine operates mainly under light loads, then it is advantageous for the value k ng [see formula (10)] was correspondingly less.
Encyclopedic YouTube
-
1 / 5
Mathematically, the definition of efficiency can be written as:
η = A Q , (\displaystyle \eta =(\frac (A)(Q)),)Where A- useful work (energy), and Q- energy expended.
If efficiency is expressed as a percentage, then it is calculated by the formula:
η = A Q × 100% (\displaystyle \eta =(\frac (A)(Q))\times 100\%) ε X = Q X / A (\displaystyle \varepsilon _(\mathrm (X) )=Q_(\mathrm (X) )/A),Where Q X (\displaystyle Q_(\mathrm (X) ))- heat taken from the cold end (in refrigeration machines, cooling capacity); A (\displaystyle A)
The term used for heat pumps is transformation ratio
ε Γ = Q Γ / A (\displaystyle \varepsilon _(\Gamma )=Q_(\Gamma )/A),Where Q Γ (\displaystyle Q_(\Gamma ))- condensation heat transferred to the coolant; A (\displaystyle A)- the work (or electricity) spent on this process.
In the perfect car Q Γ = Q X + A (\displaystyle Q_(\Gamma )=Q_(\mathrm (X) )+A), from here to the ideal car ε Γ = ε X + 1 (\displaystyle \varepsilon _(\Gamma )=\varepsilon _(\mathrm (X) )+1)
The reverse Carnot cycle has the best performance indicators for refrigeration machines: it has a coefficient of performance
ε = T X T Γ − T X (\displaystyle \varepsilon =(T_(\mathrm (X) ) \over (T_(\Gamma )-T_(\mathrm (X)))), because, in addition to the energy taken into account A(e.g. electric), in heat Q There is also energy taken from the cold source.Probably everyone has wondered about the efficiency (Coefficient of Efficiency) of an internal combustion engine. After all, the higher this indicator, the more efficiently the power unit operates. The most effective on at the moment Nowadays, the electric type is considered, its efficiency can reach up to 90 - 95%, but for internal combustion engines, be it diesel or gasoline, it is, to put it mildly, far from ideal...
To be honest, modern engine options are much more efficient than their counterparts that were released 10 years ago, and there are many reasons for this. Think for yourself before, the 1.6 liter version produced only 60 - 70 hp. And now this value can reach 130 - 150 hp. This painstaking work on increasing efficiency, in which each “step” is given by trial and error. However, let's start with a definition.
- this is the value of the ratio of two quantities, the power that is supplied to the engine crankshaft to the power received by the piston, due to the pressure of the gases that were formed by igniting the fuel.
In simple terms, this is the conversion of thermal or heat energy that appears during the combustion of a fuel mixture (air and gasoline) into mechanical energy. It should be noted that this has already happened, for example, with steam power plants - also the fuel, under the influence of temperature, pushed the pistons of the units. However, the installations there were many times larger, and the fuel itself was solid (usually coal or firewood), which made it difficult to transport and operate; it was constantly necessary to “feed” it into the furnace with shovels. Internal combustion engines are much more compact and lighter than “steam” ones, and the fuel is much easier to store and transport.
More about losses
Looking ahead, we can confidently say that the efficiency of a gasoline engine ranges from 20 to 25%. And there are many reasons for this. If we take the incoming fuel and convert it into percentages, then we seem to get “100% of the energy” that is transferred to the engine, and then there are losses:
1)Fuel efficiency . Not all the fuel is burned, a small part of it goes with the exhaust gases, at this level we already lose up to 25% efficiency. Of course, now fuel systems are improving, an injector has appeared, but it is also far from ideal.
2) The second is thermal lossesAnd . The engine warms itself and many other elements, such as radiators, its body, and the liquid that circulates in it. Also, some of the heat leaves with exhaust gases. All this results in up to 35% loss of efficiency.
3) The third is mechanical losses . ON all kinds of pistons, connecting rods, rings - all places where there is friction. This can also include losses from the load of the generator, for example, the more electricity the generator generates, the more it slows down the rotation of the crankshaft. Of course, lubricants have also made progress, but again, no one has yet been able to completely overcome friction - losses are still 20%.
Thus, the bottom line is that the efficiency is about 20%! Of course, among the gasoline options, there are standout options in which this figure is increased to 25%, but there are not many of them.
That is, if your car consumes fuel 10 liters per 100 km, then only 2 liters of them will go directly to work, and the rest are losses!
Of course, you can increase the power, for example, by boring the head, watch a short video.
If you remember the formula, it turns out:
Which engine has the highest efficiency?
Now I want to talk about gasoline and diesel options, and find out which of them is the most efficient.
To put it in simple language and without getting into the weeds of technical terms, if you compare the two efficiency factors, the more efficient of them is, of course, diesel and here’s why:
1) Gasoline engine converts only 25% of energy into mechanical energy, but diesel converts about 40%.
2) If you equip a diesel type with turbocharging, you can achieve an efficiency of 50-53%, and this is very significant.
So why is it so effective? It's simple - despite the similar type of work (both are internal combustion units), diesel does its job much more efficiently. It has greater compression, and the fuel ignites using a different principle. It heats up less, which means there is a saving on cooling, it has fewer valves (saving on friction), and it also does not have the usual ignition coils and spark plugs, which means it does not require additional energy costs from the generator. It operates at lower speeds, there is no need to frantically spin the crankshaft - all this makes the diesel version a champion in terms of efficiency.
About diesel fuel efficiency
FROM more high value efficiency - fuel efficiency follows. So, for example, a 1.6-liter engine can consume only 3–5 liters in the city, in contrast to the gasoline type, where the consumption is 7–12 liters. A diesel engine is much more efficient; the engine itself is often more compact and lighter, and also lately and more environmentally friendly. All these positive points, are achieved thanks to higher value, there is a direct relationship between efficiency and compression, look at the small plate.
However, despite all the advantages, it also has many disadvantages.
As it becomes clear, the efficiency of an internal combustion engine is far from ideal, so the future clearly belongs to electric options - all that remains is to find efficient batteries that are not afraid of frost and hold a charge for a long time.
