Types of Renewable Energy

Sep 9, 2017   //   by admin   //   Knowledge Base  //  No Comments

Renewable energy is energy which is derived from natural processes and can be replenished constantly. There are mainly 4 types of Renewable energy:

  • Biofuel
  • Biomass
  • Geothermal
  • Hydropower
  • Solar energy
  • Wind power


Biofuel– Biofuel is a type of fuel derived from biological carbon fixation or gasification. Biofuels are originated from biomass conversion, solid biomass, liquid fuels and various biogases. These are mainly used in transportation sector since they have high density and are clean burning fuels. This is the main reason why almost all the vehicles use liquid form of fuels for combustion purposes. These are the best way of reducing the emission of the greenhouse gases. They can also be looked upon as a way of energy security which stands as an alternative of fossil fuels that are limited in availability. Biofuel production is assessed to reach 105 billion litres in 2010 and provides 2.7% of the world’s fuels for transport the biofuels. These are further divided into two types:-

First Generation Biofuels or Conventional Biofuels: These types of biofuels are obtained from conventional methods of production and derived from sugar, starch, animal fat and vegetable oils. Given below are some most popular types of first generation bio-fuels:-

–           Biogas

–           Bio diesel

–           Vegetable Oil

–           Bio alcohols

–           Bio Ethers

–           Solid Bio fuels

–           Syngas


Second Generation or Advanced Biofuels: These are non –conventional Bi o fuels mainly produced from non-food feedstock for e.g. wastes, agricultural and forestry residues, energy crops and are still underdeveloped. It includes:-

–           Biomass to Liquid

–           Cellulosic ethanol

–           BioDME/Methanol

–           Biosynthetic Natural Gas (BioSNG)

–           Bio-oil/Bio-crude

–           Algae biofuels

–           Wood Diesel

–           Bio hydrogen

–           Bioelectricity/CHP


Biomass – Biomass is biological material derived from living, or recently living organisms. Biomass is carbon, hydrogen and oxygen based. It is derived from numerous sources, including the by-products from the timber industry, agricultural crops, raw material from the forest, major parts of household waste and wood. It is used to generate electricity with turbines and gasifiers or produce heat and is an important source of energy and the most important fuel worldwide after coal, oil and natural gas. These can be further converted to other usable forms of energy like methane gas or transportation fuels like ethanol and biodiesel and other biofuels by various conversion processes like Thermal conversion, Chemical conversion, and Bio Chemical conversion.

Geothermal Energy– The origin of the word “Geothermal” comes from the Greek word “Geo” which means Earth and Thermal means heat So Geothermal energy is produced from naturally occurring steam and hot water from Earth’s crust. At the core of the Earth, thermal energy is created by radioactive decay and temperatures may reach over 5000o C. Heat conducts from the core to surrounding cooler rock. The high temperature and pressure cause some rock to melt and leads to the formation of ‘magma’. The global installed capacity for geothermal energy is 28 GW. It is originated from radioactive decay of minerals inside the Earth’s surface. It is clean, cost effective, reliable, sustainable, and environmentally friendly. It can be used for greenhouses, fisheries, mineral recovery, thermo-dynamical processes and electricity. The geothermal resources are more than adequate to supply human energy needs, but aren’t exploited properly.

Hydropower – It is the energy derived from flowing water or running water. The history of hydropower is very old in form of watermills, turbines and hydraulic power pipe networks. It is mainly used for generating electricity, irrigational purposes and running machines like watermills, sawmills, textile mills, dock cranes etc. . It is the most widely used renewable form of energy constituting 16% of the global electricity consumption and 3,427 TW of electricity. It has an advantage over other forms of renewable energy as it is cheap, can be easily regulated, highly sustainable and eco-friendly as there is no CO2 emission.

Solar Energy- It is the second most widely used renewable form of energy after Hydropower. It is obtained from harnessing radiant light and heat from the sun. They are broadly characterised in to Active solar and Passive Solar depending upon their capacity to receive sunlight. Active solar technologies use photovoltaic panels and solar thermal collectors while Passive Solar technologies without solar ovens, indoor heating techniques, or orienting a building towards the sun without the use of mechanical and electrical devices.

It has a wide range of applications including solar heating, solar photovoltaic, solar thermal electricity and solar architecture. It is indigenous, inexhaustible, sustainable, cheap and reduces pollution. In 2011 the photovoltaic capacity world-wide was 67.4 GW with an annual increase of 69.8%.is expected to grow to 1,443 GW by 2020. According to IEA “solar energy is one of the biggest resources that have shown steady increase and will provide a third of the total energy by 2060.”

Wind power- It is the conversion of Kinetic energy of wind into mechanical or electrical power. Wind power is also an ancient form of renewable energy for sailing, irrigation, grinding and pumping seawater for salt-making. It is now also used for generating electricity by using wind turbines. It is widely used at small scale generating   50 kW of electrical power. It is free, efficient, clean, produces no greenhouse gas or pollutants, can be setup in a very small area. But the wind capacity is highly dependent upon the speed and strength of wind and wind penetration since it is unreliable. According to a report by Energy Saving Trust almost 30 to 40 per cent of the country’s electricity needs will be provided by wind power by the year 2050. Presently wind capacity is growing at over 20% annually, from 198 GW in 2010 to 238 GW in 2011 and generates 437 TW h of electricity, around 2% of total electricity generation.


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