Exploring Biochar: History, Characteristics and Uses
Biochar is a natural material that can be created in several ways.
It is formed naturally when the feedstock materials are burnt or heated, the temperatures involved are much lower and the molecules form into carbon dioxide, carbon monoxide, hydrogen, and tars plus other gases depending on the material being burnt.
It can at lower temperature in the absence of oxygen over a period of time such as in compost pile that is self combusting, you can see this happening when a compost pile is smouldering away over several days or even weeks. It also can be formed during a forest fire when burning wood is covered by ash and in the absence of oxygen biochar will form. Alternatively, it can be formed when the feedstock is heated to a much higher temperature (400-700 degrees) thereby forcing out the tars and gases (H2 CO and CH4) and these can be used to re-combust which in turn heats up the process even more.
The key to the process is that most of the carbon held in the feedstock remains as a solid to form biochar. This material has several important properties:
- It is inert meaning it doesn’t react to oxygen,
- It doesn’t react either anaerobically or aerobically, which means it will remain as biochar for hundreds if not thousands of years.
- It is particularly porous, meaning
- It will adsorb minerals and nutrients
- It holds and releases water in the same way as does a sponge
- It provides an excellent environment for fungi, microorganisms, including earthworms.
Biochar can be made from natural materials such as wood, husks and even manure. Any natural organic material is made up of carbon. One of the key building blocks for life.
Most important, that the process of pyrolysis (the process which forms biochar) means that the carbon remains within the biochar and not released to the atmosphere in the form of carbon dioxide or monoxide. It is therefore one of the few forms of carbon capture.
Since 2009 there have been over 32,000 research papers written on and about biochar and its application not only to the land, but also for industrial uses. However, there has not been much biochar available for commercial use. In 2020 only 15,000 tons of biochar was produced in the Europe, of which just 1,000 was produced in the UK. By 2022 some 30,000 tons was produced in Europe and by 2023 this had risen to 60,000 tons. Huge growth, yet not so much in the UK.
Horticulture
For its water retention properties alone, biochar must be considered a valuable material to add to plants whereby research has shown that 30% less water needs to be applied as the biochar acts like a sponge. plants. More importantly, it is an excellent replacement for peat compost which is extremely environmentally unfriendly and the sale of which is being banned as from 2027.
Biochar compost is a great medium for supporting plant growth. It provides a wonderful environment for all types of plants, vegetables and fruit to grow healthily.
It will improve your roses, pot plants, salad plants, vegetables, lawns.
Agriculture
For the last 100 years or so industrial farming has supported the huge increase in world population. It is estimated that if nitrogen fertiliser were banned, half the world population would starve. This obviously is very good. But what is not so good is that nitrogen from the fertilizers has been running into our water courses over the years and this has caused some serious unintended consequences such as the growth in algae causing plumes that go out in to the sea and it is also starving the rivers of oxygen resulting in fish being unable to breathe. Nitrogen is also is very energy intensive to make as it is chemically fixed from air at high temperature. It is then transported many miles before being applied to farmland. This is all well documented; farm use of nitrogen fertiliser is estimated to contribute over 1% to global warming through its carbon footprint, when nitrogen emissions are added, this increases to over 2%.
Biochar Uses
Arable land biochar will add soil organic matter, act like a sponge, by retaining water when it is dry on account of its cation effect, and allow water to run through when it is very wet, on account of its porosity.
Biochar will naturally (through its cationic properties) hold onto nutrients, reducing runoff, but still make available those nutrients when plant roots draw up the nutrients in the photosynthetic process.
It provides a wonderful habitat for fungi and microorganisms, as well as for worms and other insects.
An increasing amount of research is demonstrating the benefits of biochar to arable production with some staggering evidence of increase crop yield relating to a wide variety of vegetable, fruit and cereal crops. There have been reported increased yields of over 30% in cash crops and grapes. Other studies show increase in cattle weight by 50% justifying a value for the biochar of up to $5,000 per ton.
Arable
There is evidence to suggest there is a significant increase in yield when biochar is mixed with NPK fertiliser for six weeks or so before application.
Numerous scientific research papers provide evidence that biochar will:
Reduce nitrogen runoff, retain nutrients in the soil so they are more available to plants reduce nitrogen oxide and carbon dioxide emissions.
Pasture
By adding our biochar and/or biochar soil conditioner, you will see the return of a greater variety of plant matter, such as grasses, clover …. You will also see the recovery of microbes, fungi and earthworms.
Livestock
Along with the benefits of applying to pasture land, you can add biochar to feed and trials have shown that this will add 50% to the weight of cattle.
Vineyards
There is a growing amount of research supporting significant increase in yields and a lower requirement for watering vines. Vineyards in California, Switzerland and France have shown significant increase in yields.
