What is the cheapest source of renewable energy ? - Biomass

The conventional energy sources are rapidly depleting because of their excessive use in the modern world. And that's why energy or power generation sectors are very much interested in the utilization of renewable energy sources. The conventional energy source includes Natural Gas, Coal, Nuclear Energy, Crude oil etc. The price of these non-renewable fuels is almost touching the sky and getting closer every day. But the price of utilization of non-conventional energy source is not very cheap either. Cheap renewable energy source promises a greater power generation with a cleaner environment.

Expensive Conventional Energy Sources

Crude Oil

According to Brent Crude Oil the price of one barrel oil was $116! Yeah that’s right and yet oil is expected to remain the predominant source of energy production! The demand of oil will increase by 1.7% in the year of 2025 because of the energy consumption in USA and developing Asia. So it is high time we should look forward for a cheap reliable energy source. 

Natural Gas

Another very attractive non-renewable fuel is Natural Gas. According to the estimation the use of natural gas will be increased by 67% by the year 2025. And therefore the consumption of Natural Gas will be 151 trillion cft. If the consumption increases in that rate then it can be predicted that the life of Natural Gas will be very short on The Earth. 


70% Steel production companies uses coal as fuel. 38% of the world’s electricity generation comes from coal. It has high calorific value but at the same time very detrimental to the environment. The high quality coal comes in exchange of a high price!

Nuclear Energy

Uranium is the main fuel for producing energy by nuclear fission reaction.  U235 is the primary fuel for nuclear power generation. According to World Nuclear Association the price of 1 kg Uranium stands US $2360 (After conversion enrichment, fabrication)! And it is only the operating cost!
Capital cost + Plant operating cost + External cost = $5300/kW!

Cheapest renewable energy sources

Expensive Non-conventional or Renewable Energy Sources

Solar Energy

Sun is the source of energy. The energy from the sun in 19 trillion toe (Ton of Oil Equivalent)/year. And the world’s energy consumption is only 9 billion toe. So a fraction of sun’s energy can fulfill the energy needs. Sun’s energy is extracted mainly by solar collectors. Photovoltaic Cells (PV) are used to store the energy from sun. A single solar panel for household use can cost up to $35000 according to the power output. And this cost does not account the taxes, battery and installation cost! So clearly it is not the cheapest source.

Wind Energy

We get wind because of the pressure difference on the different areas of the earth. The air moves from high pressure to low pressure area and it causes the wind. Wind energy is actually derived from solar energy because Sun heats the earth and creates temperature differences. Hot air expands and rises up and cool air near the oceans rushes and fill that space. That’s how air is circulated. Wind energy potential is not available for use in all the places. Energy density and normality depends on geographical locations. Wind energy is very erratic and irregular. Wind turbine design is very complex and needs a good investment. To create a large plant based on wind turbines, capital intensive technology is needed.

Geothermal Energy

The interior of the earth is full of molten materials. The inner core has solid materials and the outer core is filled up liquid rock named Magma (4000 degree Celsius). Geothermal resources can be divided into this two parts –

  •      Liquid dominant resource, which involves
  1.        Flash steam power plant 
  2.        Binary Cycle Power Plant
  •      Vapor dominated resource.

Though geothermal energy is a very good potential source, it has some limitations. Geothermal energy is available in the geothermal sites only.

Ocean Energy

It is kind of hydro energy but it is mainly derived from Thermal radiation of the sun. The surface water of the ocean is heated but the deep ocean water still remains cool. These temperature difference can be used to get OTEC (Ocean Thermal Energy Conversion). From the 19th century scientists are trying to make this plant work but it is not that popular because of the high cost of the plant. It needs very large diameter pipe which is needed to be submerged a kilometer or more than that to get the cool water.

Cheap Non-Conventional Energy Source

Hydropower source – Tidal Energy

Hydro power can be got from tides and waves. Tidal power plant needs mechanical equipment. This energy is mainly due to the pull of moon.
It can be
  •          Single basin single tide
  •          Double basin single tide
  •          Double basin with the power house in the separating dam.

 It can be proved very useful for the countries having large water reservoirs. The fuel cost is absolutely nil. But the erection of this type of plant can take years. And the rate of return is very low. So the plant owners or government can suffer, running this type of power plant. But it is one of the cheapest source of renewable energy.


According to my studies I think Biomass is the most potential source for energy production. It can be got from forest areas, agricultural residues, Urban wastes, Industrial wastes and natural vegetation.

Biomass – The Cheapest source of Renewable Energy

Yes, I would say biomass because it can use aquatic crops, vegetable oil crops, and animal wastes even human wastes for fuel production. Every day almost 42 million tons of solid waste and 6000 million cubic meters of liquid waste are generated in urban areas. What you will do with all these huge waste materials? If these are utilized to produce power than it would be much better for our environment. And these waste materials are not expensive for sure. Biomass can provide us with biofuels and biogas.


Charcoal – These possess high energy density and can be burned at temperatures high as 600 degrees. Very good for household, commercial and industrial uses.

Briquetting – It can be produced from coconut shells, saw dust, wood chips etc. This are made into high density fuel element.

Vegetable oils – Palm, coconut, cotton, rapeseed and soybean oils can be used as bio fuels. These can mixed with diesel to form premium grade fuel.

Biogas –

Biogas can be produced from digestion of the waste materials like human waste, animal waste and plant waste.  Biogas is mixture of Methane, Carbon dioxide, Hydrogen, Hydrogen Sulfide and Nitrogen. Here Methane CH4 is predominant (55 -65%). Methane is very clean burner.
Biogas Plants are also very cheap to fabricate. There are two very popular designs to produce biogas
  •         Floating Drum Biogas Plant (KVIC model) or Chinese Biogas Plant
  •         Fixed Dome Type Biogas Plant (Indian Biogas plant design, Janata Model)


Biodiesel can be produced by mixing organic oil with diesel. Non-edible oil seeds are much preferred for the production of the oil. These produces very small amount of CO2 and zero sulfur. These fuels have very high flash points so they are easily transported without any danger of self-ignition and combustion. This fuels give high octane ratings. Biodiesel can be produced from Jatropha Curcus, Jojoba, Sunflower, and Soybean and also from peanut. Amongst them Jatropha is the cheapest. It is economically favorable and it costs $0.08/kg of seeds! Where Jojoba seeds costs $3.39/kg.
So Biomass derivatives – biofuels, biogas and biodiesels are the cheapest source of renewable energy.


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