How Electricity is Generated from Biomass

Biomass is biomaterial from living or recently living organisms such as timber, agriculture wastes and animal manure. There are several ways can get useful renewable energy from biomass other than burning it directly. In this article I’m going to explain how we can how we can generate electricity from biomass. 

If you are simply looking for a general overview of biomass, go to Biomass Energy Pros and Cons.

Author  From poop to power

There are several methods to convert biomass into electricity. The first one is simply to burn biomass directly, heat water to steam, and sending it through a steam turbine, which then generates electricity.

The second way requires gasification of biomass. A biomass gasifier takes dry biomass, such as agriculture waste, and with the absence of oxygen and high temperatures produces synthesis gas (CO + H2), also known as pyrolysis of biomass.

The gasification process turns wet biomass, such as food waste and manure, into methane (CH4) in a digestion tank. Both methane and synthesis gas (syngas) can be used in a gas engine or a gas turbine for electricity production.

Below is a short video of a biomass/biogas power plant in a familiy farm in Ontario, which by using manure that otherwise would go to waste, generate enough electricity to power 800 homes (1.3MW).

A third way to produce electricity from gasified biomass is by using fuel cells. If we have biogas/bio-syngas with high enough purity we can use fuel cells to produce bio-electricity. The fuel cells breaks down quickly if the gas in any way contains impurities. This technology is not yet commercial.

Biofuels, like ethanol, biodiesel and bio-oil can be also be used for power production in most types of power generators built for gasoline or diesel. 

There are several other types of new interesting biofuels coming such as algae biofuel. Read more about this in What is Biodiesel from Algae?

Efficiency of biomass/biogas power plants

The generation of electricity from biomass results not only in electricity, but also a lot of heat. A traditional gas engine will have an efficiency of 30-35 percent. Gas turbines and steam turbines will end up at around 50 percent.

It is common also use the from these processes, thus increasing the overall energy efficiency. In countries with good governmental support for renewable energy, such as Germany and the Netherlands, there are many plants that combine heat and power production from biomass.

The biogas plant cost does indeed go up, but the long term savings that come with better energy efficiency is in most cases worth it.

For further information log on website :
http://energyinformative.org/how-electricity-is-generated-from-biomass/