The development of alternative energy ensures the receipt of the cheapest possible energy using renewable (inexhaustible) sources of raw materials necessary for its generation. However, alternative energy sources do not always allow achieving the desired result, sometimes remaining an economically unprofitable way to solve the energy problem.
Types of green energy
Modern energy is an industry where various natural environmentally friendly energy sources are widely used:
- solar radiation;
The technologies of energy transformations, which underlie the use of these types of natural resources, make it possible to partially solve the problem of energy resources’ shortage, but they are far from always environmentally friendly.
Solar power, solar batteries
Solar radiation is considered a promising direction in the development of alternative energy.
Among the advantages of installing solar panels there are:
- minimal impact on the environment in the process of energy generation;
- high efficiency of installations;
- lack of noise;
- the possibility of installation in almost any region of the planet.
Using only 1 kg of silicon, you can get as much energy as a thermal power plant produces with 75 tons of oil. The amount of electricity consumed is much less than the amount generated by the panels, therefore, in some cases, their payback occurs within a year.
However, solar radiation, like any alternative energy sources, has a number of disadvantages. Chief among them is the uneven density of the incidence of sunlight in different areas throughout the year, which is the reason for the decrease in the efficiency of solar panels.
Other disadvantages of using panels are:
- the need for periodic cleaning of the surface from contamination;
- use of significant land areas for the installation of structures on an industrial scale;
- use in the production of blocks of hazardous substances that have an impact on the environment.
It is estimated that over the lifetime of a solar module, approximately 0.02 g of cadmium telluride is released into the atmosphere per one GWh of electricity. The indicator is quite small, however, with a full transition to solar energy, its value will increase tens of times.
The production of one panel requires approximately 68.7 MWh. When the panel generates 2.4 kWh per day (there are more powerful analogs), the installation will produce approximately 3.16 MWh per year.
The problem of recycling has also not been given due attention. Manufacturers of solar panels do not always offer ready-made recycling programs, leaving open the question of their storage / recycling.
Wind power, wind power plants
The streams of wind masses can be successfully converted into any energy: mechanical, thermal, electrical, using it in various industries.
The transformation of wind energy takes place by means of a wind generator – an installation with a vertical / horizontal axis, equipped with two, three or more blades, in which an electric generator is mounted. One such structure with a capacity of 1 MW allows saving about 30,000 tons of coal, about 12.500 tons of oil over 20 years of operation.
Main advantages are:
- the use of safe raw materials – natural wind masses;
- relatively quick payback when used on an industrial scale – 1-2 years;
- no harmful emissions.
- Wind power plants produce 25-30 times more energy over the same period of time than they consume over the same period.
The main disadvantages are:
- volatility of generated resources due to the variability of wind strength;
- the need to provide infrastructure for the transmission of the received electricity to the consumer due to the remoteness of the wind turbines;
- the use of expensive equipment (battery, inverter) when using small wind power plants at home;
- significant noise interference.
The statement about their complete environmental safety is also not entirely true. The manufacture of wind turbines requires the cost of remelting metal, casting plastic, copper parts. The production of concrete necessary for the formation of the base also requires certain energy resources, and the manufacture and subsequent disposal of batteries are energy-intensive unsafe processes.
Converting the energy of the water flow allows people to get cheap electricity, the generation of which at hydropower plants is accompanied by a relatively small impact on the environment.
- absence of harmful emissions during work;
- the efficiency is 85-90%.
However, the construction of structures that provide the possibility of energy transformations is accompanied by an irreparable impact on the ecosystem of the territory where the construction is underway.
The main disadvantages are:
- flooding of land;
- impoverishment of flora and fauna;
- the possibility of equipping powerful hydroelectric power plants only in places with significant water resources;
- significant construction costs.
By using clean energy sources, you can reduce the consumption of non-renewable raw materials or completely replace them. Liquid, solid, gaseous biofuels are a versatile means of generating energy, regardless of the region of its use.
- the possibility of using various raw materials to release energy biomass;
- general availability;
- compliance with the neutral level of absorbed / emitted carbon dioxide;
- low cost of raw materials.
Disadvantages of operating bioenergy plants:
- the use of significant land for growing crops;
- emissions of harmful substances during the combustion of biomass (sulfur – 0.2%, ash – 3-5%);
- soil contamination with pesticides;
- violation of the ecological balance of the adjacent territory;
- the need to organize an uninterrupted supply of biofuel.
There is no “perfectly safe” cost-effective alternative energy source. The feasibility of using each of them is determined by a combination of multiple factors.