Biomass is one of the oldest energy sources around. At the same time, a great deal of confusion surrounds its designation as a renewable energy source. Does biomass really count as a sustainable energy source? Can it be considered an efficient source of energy?
The use of biomass as an alternative to fossil fuels has seen a growth spurt in recent years, a tendency that is bound to increase as renewables continue to go mainstream. And of course, as with other energy sources, you can improve biomass performance by measuring and analysing its consumption, thus making it even more efficient.
Read on to find out how…
What is biomass?
Still confused about what biomass is? Wondering about where and how it can be used? Let’s clear things up with a definition:
Biomass refers to all organic matter of vegetable and / or animal origin that can be transformed into energy.
Some examples include:
- forest and agricultural residues
- organic matter from sewage
- urban solid waste (organic waste), and
- other wastes derived from industrial processes (sawmill residues, black liquor…)
Organic matter can be transformed into heat energy, electrical energy or biofuel. Here are some practical applications of biomass as an energy source:
- Biodiesel used in vehicles
- Wood pellets used in combustion boilers for domestic and industrial heating installations.
- Wood chips
- Olive pits, also used in boilers for heating
- Electric co-generation in industrial kilns for drying wood
- Biogas which produces electricity via co-generation
Biomass in the UK
Biomass is playing an increasingly significant role in Britain’s energy mix, mainly due to the conversion of existing coal plants into biomass generation plants. In 2015, the UK generated 9% of its electricity from biomass, doubling from 2005 levels and became the largest importer of wood pellets in the world.
The map below shows all the working biomass power stations in Great Britain:
The factors driving this upshot in biomass use are several:
- The growing necessity to move away from a fossil-fuel based economy and toward renewables
- To meet climate change targets, including carbon emissions reduction and reporting regulations
- Increases in agricultural production and the need to find alternative uses for excess or waste generated
- Technological advances that optimise the process of biomass energy production
- An regulatory environment that favours the development and use of biomass as fuel, especially thanks to subsidies that convert coal plants to biomass
For instnace, the biggest power station in the UK that supplies 7% of its electricity, has already switched 3 of its 6 units from coal to biomass, and will convert a 4th in December thanks to an EU-approved government subsidy.
So does biomass count as a renewable energy source?
Well, it depends on who you ask.
Many energy firms claim that biomass is a more reliable source of power than wind or solar.
Although some environmentalists reject the idea that biomass is sustainable at all, both the UK and EU governments officially consider it a low-carbon energy source.
The underlying premise is that since trees absorb carbon as they grow, forest growth will balance the carbon emitted by burning wood for energy. Further, under international greenhouse gas accounting rules set down in the Kyoto Protocol, biomass emissions are recorded in the land-use sector rather than the energy sector in order to avoid “double counting” emissions.
In reality the situation is much more complex, argues a report by Chatam House, a non-profit think tank in London. A variety of factors influence the overall emissions from burning biomass, including the type of wood used, its fate had it not been used for energy, and what happens to the forest from which it was sourced. Another important factor is the “carbon payback period” or how long it takes for forests to grow back and re-absorb biomass emissions.
While the debate is unlikely to be resolved anytime soon, it is safe to say that while the use of waste biomass (feedstock that do not require extra harvesting, such as sawmill residues, black liquor or post-cosumer waste) can be carbon-neutral, biomass obtained from other sources (such as living forests across the ocean) might not be so sustainable.
How much does biomass energy cost?
The million-dollar question… does burning biomass make business sense? As in most cases, it depends on the type of project and resources available. Location plays an important role too; a biomass installation in a remote field in the countryside differs greatly from one in the center of the city, or if you have chosen a pellet boiler or olive pit as your source material.
The price of a biomass boiler can vary, depending mainly on the type of the boiler, fuel type and size. An ordinary commercial installation aimed to heat two or more buildings can cost approximately £20,000.
In terms of the cost of fuel, biomass fuel can deliver cost savings. According to the Forestry Commission of England, woodfuel tends to be be cheaper than fossil fuels when replacing electric, LPG, coal or heating oil. The average price of wood pellets is around 3.1p/kWh, which is considerably lower than mains gas at 4.9p/kWh, while electricity costs a whopping 15p/kWh.
However, the price of wood pellets is likely to become more attractive going forward due to its relative stability. While gas prices have continued to rise in recent years in the UK, biomass sources are independent of the fluctuating prices of imported fuels such as gas and oil.
Is energy from biomass efficient?
As with any other energy source, you can optimise efficiency even further by applying the right technology tools.
Using a flexible energy management solution, you can monitor this energy source easily and analyse its overall efficiency. If you detect that your installation is consuming biomass excessively, you can adjust the consumption rate or replace your boiler with a more efficient one.
For example, if we compare older models of biomass boilers with more current ones, the latter are much more efficient since they consume less energy to produce the same heat.
And how do we increase the efficiency of modern installations? Easy peasy!
If we add analysis and control capabilities to our installations, we can make them even more efficient. With the right energy management software you can measure, analyse and control the consumption of biofuel in addition to other sources like electricity, gas and thermal. This powerful aM&T solution offers the data-driven insights you need to understand how to make the necessary adjustments and make your installation as efficient as possible.