OVERVIEW OF RENEWABLE ENERGY
1. The concept of renewable energy and alternative energy
Renewable energy is the energy generated from natural processes and is constantly being added. This natural source includes sunlight, geothermal, wind, tide, water and various types of biomass. This energy is not exhausted and is constantly being regenerated.
Alternative energy is the term used to refer to an alternative energy source for fossil fuels. This is a non-traditional energy source with little impact on the environment. Most definitions say that "alternative energy" is not harmful to the environment, which is different from renewable energy with or without significant environmental impact (IEA, 2014).
2. Picture of renewable energy development in the world
2.1. Development history
Before the 19th century, most of the human energy used was renewable energy, especially the traditional biomass that appeared from 790,000 years ago. By 1823, inventor Samuel Brown created the internal combustion engine and demonstrated the potential of fossil fuels for electric vehicles. By the 1830s, the development of steam trains and locomotives increased the demand for fossil fuels, while the transportation and trade of fossil fuel products also increased. In the late 1830s, scientists discovered photoelectric compounds, releasing energy when exposed to light. This discovery led to the development of solar cells and solar energy. In 1839, William Robert Grove invented the first hydrogen fuel cell, in which electricity was extracted from the reaction between hydrogen and oxygen.
Wind energy is the second oldest renewable energy source, used to sail on the Nile from 7000 years ago. By the 1970s, environmentalists were promoting the development of renewable energy sources in both directions, by replacing the depleted oil source, and at the same time escaping from dependence on oil, and the turbines. The first wind turbine was born. Although solar energy has long been used for heating and cooling, it was not until 1980 that solar panels began to be built on solar battery fields.
The first wind turbine was born by the 1970s
In June 2004, representatives of 154 countries for the first time met in Bonn, Germany at an international conference held for governments around the world on renewable energy. The Renewable Energy Policy Network for the 21st Century (REN21) has emerged as a network of stakeholders on global renewable energy policy with the aim of facilitating the exchange of knowledge , policy development and participate in activities aimed at the transition to renewable energy. At that time, the potential of global renewable energy, investment, policy and integration were interested. However, even ambitious forecasts do not foresee the strong development of renewable energy that took place in the last decade.
Global awareness of renewable energy has changed dramatically since 2004. Over the past 10 years, advances in renewable energy technology have continued to grow, and many technologies have proven their potential and quickly deployed.
2.2. The situation of research and development of renewable energy
According to statistics and forecasts from the US Energy Information Administration (EIA), the world's energy consumption increased by 57% from 2004 to 2030, in which the average annual electricity consumption increased by 0.46 kW/hour/person. Increasing energy demand has increased the amount of CO2 in the atmosphere. If in 2004 there were 26.9 billion cubic meters of CO2, then by 2015, this figure will increase by about 33.9 and in 2030 will be 42.9 billion cubic meters. In order to overcome the traditional energy exhaustion and limit environmental pollution caused by energy exploitation, the research and development of alternative clean and renewable energy sources such as solar radiation, Wind, geothermal, biomass, hydropower, tides, currents, waves and some other energy source are needed. Therefore, many countries around the world, especially those with developed industries, have come up with energy development strategies. In 2005, the US Congress approved the Energy Strategy Act of 2005 with additional provisions on renewable energy at sea including the promotion of marine energy products, the ordinance on investment incentives and reduce taxes on marine energy such as tides, currents and waves and encourage research and development of related mining technologies. The Act also authorizes and encourages the Energy Secretariat to invest in marine energy technology and has introduced the Federal Renewable Power Standard (RPS), which considers marine energy to be the source. Renewable energy is promising. The RPS also outlines the goal of producing 10% of renewable energy by 2020. Scotland's Natural Heritage Commission's Strategy No. 4 of January also aims to produce 40% of electricity from the renewable energy by 2020.
The United States Electrical Research Institute (EPRI) is the world's leading research agency for energy extraction methods, with a special focus on renewable energy sources. According to EPRI's prediction, by 2030, the electricity generated from renewable energy sources will be 737 TWh (1TW = 1012 kW). EPRI also announced that in the coming years’ technology to exploit renewable energy sources such as solar radiation, biomass and wave energy will be prioritized for investment. Since the 1970s, countries such as Norway, Sweden, the United States, France and Japan have also conducted research programs on wave energy. And the first wave power plant was built in Norway in 1984 and completed in 1986.
It is estimated that in 2012, renewable energy provided about 19% of the final global energy consumption and continued to increase in 2013. Of this total in 2012, modern renewable energy accounted for about 10%, the rest (9%) is from traditional biomass. Thermal energy from modern renewable sources accounts for about 4.2% of total final energy use; hydroelectricity accounts for about 3.8%, and about 2% is provided by wind, solar, geothermal and biomass and biofuels. Renewable energy combined with modernity and tradition still maintains in 2011.
In 2013, renewable energy faced a decline in supportive policies and uncertainty in many European countries and the United States. Grid-related restrictions, some power companies are concerned about growing competition and continuing global funding for fossil fuels is also a problem. However, in 2013, renewable energy was still actively developed.
The market for production and investment is expanding across the developing world and the evidence is clear that renewable energy is no longer dependent on a small group of countries. With technological advances, reduced costs and innovations in financial mechanisms - all largely thanks to policy support, renewable energy prices are becoming increasingly cheaper for a large range of consumers across the world. In some countries, renewable energy is very important to meet current and future energy needs.
As the market for renewable energy became globalized, the renewable energy industry responded by increasing its flexibility, diversifying products and developing global supply chains. Although some industries still face difficulties, especially solar and wind power. However, the picture brightened up in late 2013, when many solar PV (PV) and wind turbine manufacturers came back, and profits increased.
The strongest development took place in the energy sector with global capacity exceeding 1,560 gigawatts (GW), an increase of more than 8% compared to 2012. Hydropower increased by 4% to about 1,000 GW, and other renewable energy increased. nearly 17% to more than 560 GW. For the first time, solar power is higher than wind power; Solar and hydropower are essentially bound, each accounting for about one-third of the new capacity. Solar power has continued to grow at a fast pace, averaging nearly 55% per year over the past 5 years.
Wind power capacity had the highest increase among all renewable technologies in the same period. In 2013, renewables increased by 56% to the global electricity grid and had a higher share in some countries.
By the end of 2013, China, the United States, Brazil, Canada and Germany were still the leading countries in renewable energy installed capacity; Leading countries in non-hydro capacity (electricity generated from renewable energy sources such as solar, geothermal, biomass, wind and landfill) include China and the United States. and Germany, followed by Spain, Italy and India. Ranking of the top 20 countries in the world in non-hydro capacity, Denmark is a leader in total per capita capacity. Uruguay, Mauritius and Costa Rica are among the leading countries in renewable energy investment and new fuels compared with annual GDP.
Benefits of combining thermal power plants
In the area of heating and cooling, trends include increasing renewable energy use in combined heat and power plants; provide renewable energy for heating and cooling systems in the region; hybrid solutions in the field of construction improvement; and increased use of renewable heat for industrial purposes. Heat from modern biomass, solar energy and geothermal energy sources make up a small part, but the proportion of global heat demand is gradually increasing, estimated at about 10%. The use of modern renewable technologies for heating and cooling is still modest compared to their great potential.
In recent years, liquid biofuels have grown unevenly, however, production and use have also increased in 2013. Other renewable energy options in the transport sector are also increasing. more attention. Gas-based biofuels (mainly biofuels) and hybrid options such as bio-diesel natural gas buses and electric-diesel vehicles are increasingly used. Initiatives to link transport systems with renewable energy, especially at the city and regional levels, are increasing.