Biomass quality control

There are thousands of power plants around the world using biomass to generate heat and power, and hundreds of power plants are going to start using biomass or would like to convert at least part of their coal to biomass. Biomass usage is growing all around the world. Its role as a stable energy generator is undeniable. Globally, 9.1% of total energy consumption is produced by traditional biomass. Biomass is the largest heat producer and the primary renewable energy source used for district heating (See: Renewables 2017 Global Status Report)

There are a couple tricky matters when it comes to biomass. Compared to coal, biomass is an extremely heterogenous material. Even though this fact is well known, it might still offer some surprises for power plants. This article will tell you a little more about these surprises and how you can tackle them.

Today’s challenges with biomass

Power plants are increasingly using biomass to generate cleaner energy and to reach climate targets. Usually, after one or two years, they notice a large energy balance error, which means that the biomass quality wasn’t what they had anticipated. At this point, after an issue already exists, power plants start projects to investigate how to remedy these problems. Therefore, biomass quality management should also be considered when power plants are making decisions about their total investment.

What other problems or challenges could power plants face when they start using biomass? The first issue comes from the governmental side. Do governments subsidize biomass usage with same amount of money every year per MWh produced? The answer is no. There will always be changes in the amount of subsidization because of various reasons that we won’t go into in this article. A second challenge is related to optimizing combustion processes. Is it a similar process when power plants are generating heat and electricity from coal or from biomass? Again, the answer is no. Biomass material is heterogeneous. Both quality management and controlling material are extremely important. Optimizing combustion processes is vital to energy efficiency. In many cases, the annual costs of buying biomass is the highest expense for power plants. For this reason, it is important to know the actual value of every single load that comes to the power plant area.

Biomass in the future

Luckily for future generations, the use of cardboard is rapidly growing and replacing the use of plastic as packaging material. When we think about sustainable harvesting and biomass usage, more and more “better quality” biomass material is being used for the cardboard manufacturing process and “poorer quality” biomass will be material that power plants use as fuel. This means that usage of, for example, forest residues and other underestimated biomass materials will increase. When power plants start using this “poorer quality” biomass it means two things. First, this material will be increasingly heterogeneous, and, secondly, power plants must still become more energy efficient. You might be wondering, how in the world can I improve our power plant’s combustion processes, keep up with emission limits, and operate costs efficiently? The simple answer here is that you need to know what material you are buying to optimize combustion processes. How do you do that? You must take representative samples from every load that arrives. This is the only way to control material flow and quality; it is the only way to know what material you are buying and how much you should pay for it.

In Finland we have been using biomass for about 40 years to produce heat and power, and it is the crucial fuel for our enormous district heating system. In Finland, district heating networks heat about 47% of our country’s buildings (Finnishenergy). We have acquired a lot of knowledge about how to use biomass in sustainable ways and how to be energy efficient. We also have a lot of knowledge in how to conduct quality management the right way. All you need to do is ask us.