Old methods, new techniques: what is biomass energy?

Bioenergy is a fancy name for something which is as old as humanity itself: the use of biological fuel in order to create energy. But how far has it come? And is it really the solution we’ve been looking for?

Ancient technology, new solution: pros and cons

Essentially biomass energy production has been with humanity since the first time we began using fire to cook and keep warm. Only recently has it become considered to be a viable alternative to some of the non-renewable materials that we often use for energy production on a grander scale.

While there are still a lot of problems, including the continuation of emissions, there are some serious advantages offered by biomass energy production:

• Using existing infrastructure-Due to the nature of this type of energy production, quite often power plants which use fossil fuels, such as coal, can be converted to the use of biomass with minimal difficulty.
• Renewable-The fuels used in biomass energy creation are quite renewable. We’ll touch on the various sources in just a moment, but as a general rule, they use plants or other forms of biological matter which can be sourced readily.
• Carbon neutrality-Nature has a way of “locking up” carbon in the form of plants, which biomass then uses to create energy. The overall process ends up being carbon neutral, despite the pollution emitted, unlike fossil fuels which produce carbon dioxide which otherwise would have remained trapped underground.
• Waste reduction-Some forms of biomass can help with overall waste reduction within the environment by utilizing things that would have otherwise just ended up being discarded.
• Wide availability-Biomass can be utilized essentially anywhere humans can live due to the ubiquity of plant and organic waste matter in the environment.

While it isn’t without issues at the end of the day, there really are quite a few advantages offered.

Like all forms of energy, however, there is a serious tradeoff at the end of the day and all of the following must be taken into account as well when it’s being looked at as a solution:

• Polluting-Most forms of biomass still cause pollution to be released into the atmosphere. While solar and other “traditional” renewables are also quite green, biomass still produces considerable amounts of pollution which must be taken into account.
• Inefficiency-Biomass energy really isn’t all that efficient when compared to fossil fuels. This is most apparent in the heightened use of ethanol in vehicles but applies across the board to most forms of energy brought from biological matter.
• Deforestation-While not all plants use wood, it’s definitely one of the leading things used to produce fuel for biomass power plants. This can lead to deforestation if the wooded areas used to supply things aren’t carefully managed.
• High space requirements-Biomass takes a lot of space in order to produce energy. While this can be avoided with some forms of production, it remains a serious concern for the widespread use of bioenergy.
• Expensive-This is an expensive form of energy. From transportation to fuel to the sheer inefficiency of the fuel’s usage, there is a lot of monetary expense involved in utilizing biomass.

Types of biomass energy

Of course, the discussion isn’t complete without taking a look at the various forms through which the energy can be produced.

Combustion

Combustion is probably the original form of energy used by humans. When we’re talking about large-scale biomass the idea is to use it similarly to coal or natural gas: the matter is caught on fire, the heat produces steam, and the steam spins a turbine which is attached to a generator.

From there it generates electrical energy.

Combustion is the essential form of biomass, the question at the end of the day is what is being combusted to generate the thermal energy for steam conversion within the power plant.

Gasification

By heating matter in the limited presence of water vapor or oxygen organic matter can be converted into a combination of CO2, hydrogen, and CO.

This mixture is called syngas, and can then be combusted in order to create energy.

This is a low yield process when organic mass is used, instead of the traditional bed of coke, and it’s more often used along the way to creating fuels with higher energy values such as methane or e-diesel.

Pyrolysis

Pyrolysis consists of the degradation of organic materials without the presence of fire, but in the presence of high heat. Essentially, the potential fuel is heated to high temperatures in the presence of a vacuum in order to ensure that there is no fire involved.

From here there are three pieces of matter produced:

• Syngas
• Biochar
• Bio-oil

Both syngas and bio-oil are viable sources of energy, while biochar can be used as fertilizer. Biochar is also being looked into as a way to sequester carbon away from the atmosphere, giving it the advantage of being a potential way of lowering overall carbon dioxide levels within the atmosphere.

Bio-digestion

By exposing organic mass to bacteria in an anaerobic environment, flammable gasses can be created. This biogas can then be combusted in order to produce energy.

Fermentation

Fermentation of organic matter produces a variety of flammable alcohols which can then be refined in order to provide energy.

In many places, this form of production is the leading way that biomass is being used. In the US, for instance, it’s commonplace to see ethanol used as a fuel for vehicles.

Is biomass the energy of the future?

Biomass is unlikely to be taking over for fossil fuels in large-scale energy production any time soon, the inefficiency of the material makes it hard to recommend on a massive scale.

Instead, it seems likely that as a waste reduction and recycling technique this process has some seriously game-changing potential. The main advantage is also the source of most of the problems, however: these materials are already present and being used in various ways.

There are also some problems with the existing infrastructure on a personal scale. While ethanol may be a viable fuel source for internal combustion engines, for instance, most of these engines aren’t made to handle the temperatures and pressure which the fuel burns at. While it’s not problematic in the short term, there are some definite long-term problems with engines running on high-ethanol fuels.

There are also problems with the economics of biomass. Currently, there is no real regulation, which makes international trade of matter designated for biomass power production a bit tricky, especially since these seemingly simple materials are actually quite complex in their overall makeup.

Once again we see that alternative power sources will have to work together, along with regulation and furthering the technology, in order to have serious potential in this arena.

While some have hypothesized about the usage of large-scale biomass plants in the future, with pelletized sawdust being the most often proposed method, it’s important to consider that there are still some hefty environmental prices to pay even if the costs are minimized through the conversion of existing power plants.

That's not saying that the future of biomass is particularly bleak, however, since combustion will be required for a long time into the future.

The future of biomass

It’s quite likely that techniques for deriving fuels from organic matter are going to increase quite rapidly in the coming decades. While they’re not likely to be used as a replacement for large-scale power generation they definitely have their place when it comes to being a supplemental energy source.

Ethanol, syngas, and other biomass derivatives remain a carbon-neutral alternative to the fossil fuels which are being used at large. On the personal scale, they’re likely to become more and more important as fuel sources: they burn cleaner than fossil fuels, they’re readily available in most parts of the world, and they’re more energy compact than raw biomass like dried wood.

As part of a comprehensive plan for a greener future, they may be invaluable. The pros and cons of biomass energy are pretty clear.

Biomass energy has been with us since the beginning of our race, and it’s not likely to go anywhere.

Indeed, as part of our reduction of use of non-renewable resources, it may just be the best alternative to end-user fossil fuel products like natural gas and gasoline for the home consumer.

But, as with everything involved in the overarching needs of our planet, there is no single, simple solution and we must instead rely on the pragmatic application of the knowledge in front of us.