Biomass is a form of renewable energy, which is gaining the attention of energy providers as a low-maintenance and economically efficient alternative to fossil fuels.
It works in a similar way to nuclear energy, by creating a force strong enough to spin a turbine to produce electricity.
Take these two examples:
- Vegetation, such as trees, are gathered and burned in a factory to heat water.
- Animal droppings are collected and disposed of in a digester tank. Bacteria eat manure, and methane gas is created. This gas is used to heat water.
The temperature intensity of the water from both of these processes creates steam to spin a turbine that powers a generator, and this creates electricity.
As supplies of oil, gas and coal are expected to run out by the middle of the 21st century, innovative scientists have supported the idea of biomass – as it is unlikely the planet will run out of trees or animal droppings.
Although such energy has been used since humans first learned how to control fire, it has not been used on a large scale, unlike its renewable energy peers.
Yet, according to research by Market Research Future, by 2027, the biomass market is expected to be worth up to $108bn, as more homes and businesses move towards renewable energy.
Biomass terminology explained
Anaerobic digestion: the process where animal or food waste is broken down. This happens in an environment free from oxygen, for example, in an anaerobic digester.
Biogas: this is a gas created through anaerobic digestion and can be used as fuel.
Biomethane: a renewable source of energy produced from biogas.
The positive aspects of using biomass
There are a range of positive outcomes in using biomass for both users and for the environment:
- One of the strongest positive aspects of biomass is simply that other energy choices are running out – sources of coal, natural gas and oil will be entirely depleted by 2060. However, biomass stocks are all in an unlimited supply, from plants to trees, food waste to faeces.
- Through using food waste, dependency on landfill sites is alleviated.
- When food waste is used, the process is cost-effective. Consumers have already purchased their food and can now use scraps from their plates or a forgotten pack of spinach to power their home.
- Although burning biomass items creates CO2, if enough biomass is grown to replace what is being used, there will be a sustainable supply chain.
- Some governments have schemes in place to support those choosing biomass energy, such as the UK’s Domestic Renewable Heat Incentive (RHI). The plan allows homeowners to make a financial claim for biomass boilers, solar water heating, and certain alternative heat pumps.
The negative aspects of utilising biomass
Biomass energy has been used to support human life since the invention of fire. Yet mass-produced biomass is a very new concept, and biomass has plenty of reasons which prevent it from becoming a mainstream source of renewable energy.
- For consumers used to low-effort energy, the idea of harvesting food waste and faeces may be too much to comprehend.
- The science for biomass is not in unison. 59 scientists from across 17 countries recently spoke out against burning trees for energy, insisting that they should be planted and left alone to grow, not dug up for fuel.
- A European Commission report revealed that 86% of the EU’s wood bioenergy comes from wooden by-products, such as fallen branches, sawdust and trees cut down for forest management. However, 14% came from an unknown source. This could mean that the wood comes not from by-products but from healthy trees.
- Furthermore, the use of wasted food as a form of energy may encourage some to buy more food than they need. According to the United Nations, up to 690 million people went hungry in 2019 (a 60% increase from 2014). For those people impacted by food insecurity, biomass is a controversial and even insensitive idea.
- Biomass is not an inexpensive idea, as the costs of transporting biomass stocks (particularly trees) add up.
- Burning biomass also releases dangerous chemicals. Soot is responsible for asthma attacks, and carbon monoxide can cause nausea. But burning biomass for electricity can produce nitrogen oxides, which cause cancer. Those working with biomass will need suitable protection.
Biomass is a form of renewable energy, but it’s not entirely clean
Biomass is not as efficient as its green energy contemporaries: solar, wind and hydropower are sources of infinite energy, which are not depleted when used by humans. However, for biomass to remain renewable, the items it uses, such as trees, plants and waste, must be replaced. For waste, this is inevitable, but planting fresh trees and plants requires manual labour. Gathering and transporting the stock to a biomass factory will also cause pollution unless electric transportation is used.
Other traditional forms of green energy require less work after their initial completion. Wind turbines can be built in locations where they will work at peak efficiency, hydroelectric power stations are built next to suitable water levels, and solar panels can work anywhere in direct sunlight.
Furthermore, unlike the dangerous chemicals produced by biomass, these clean forms of renewable energy have no side effects on humans.
Biomass is being employed as a source of energy across the world
Unlike nuclear power stations, biomass can be a small-scale, at-home process.
Homes with outdoor spaces can station a biomass appliance in the garden and dispose of their food waste here.
The engineers at HomeBiogas created a kit that can convert organic household waste into cooking gas. Users filter their food waste into specific pots and leave the HomeBiogas kit to do the rest. Gas is created from the waste as it deteriorates and releases biogas. This is then returned to the owner’s kitchen as they cook the next meal. In addition, the kit creates a fertiliser for the owner to use in their garden.
Biomass can also be deployed on a bigger scale. In the UK, the government has started a £4mn fund, The Biomass Feedstock Innovations Programme, which will support organisations that want to begin their production of renewable energy through biomass.
As the pool of available fossil fuels becomes smaller, and the environmental consequences of their use become clearer, the world must expand the possibilities of renewable energy – and stop being disgusted by animal droppings.