Why Biomass-to-Energy technologies are an essential pillar in any decarbonization strategy
To achieve the 2°C target of the Paris Climate Agreement, we need to reduce the global emission to 29 Gt by 2030 (-20% of that level in 2017). As 85% of these emissions are energy-related, the main focus worldwide is on energy-related technologies.
The breakdown of the energy bill in Germany, for example, is as follows: 42% of the energy-related emissions are generated by electricity production; 28% arise from transport, 30% stem from central heat generation for industrial processes and decentral heat generation for buildings.
Nowadays, we have a broad portfolio of technologies to generate green electricity. Wind Power and Photo Voltaic (PV) are today the best examples. Whereas the options are very limited when it comes to heat generation. Especially, in the context of industrial processes, switching to alternative energy solutions, such as zero-carbon electricity, would be difficult, because this would require significant changes to the design of furnaces. Furthermore, industrial processes are highly integrated, so any change to one part of a process must be accompanied by changes to other parts of that process.¹
In this context, Biomass-to-Energy (BtE) is the best competitive choice to generate energy for district heating, industrial processes, and decentral heat generation for buildings. Even in terms of electricity, BtE is still the only renewable alternative, which can deliver a baseload.
A McKinsey study¹ indicates that BtE offers one of the most capital-efficient transitions from coal to renewables. In several industries, like steel and cement, BtE can also replace fossil-fuel by bio-feedstocks. This transition could be based on a co-firing-model or on a 100 percent biomass full-firing.
In both cases, this transition offers a way for big utilities and industries to comply with renewable targets while using their existing assets by reducing their carbon footprint from 820g CO2/ kWh for coal to 230g CO2/ kWh at full firing model. Even a co-firing business model can help coal utilities to achieve the planed EU environmental targets (below 550g CO2/ kWh).
Growing Market and promising potential
According to the “Renewables 2017 Global Status Report” by REN21, Biomass power plants provide today seven percent of the global industrial heat demand, 2.8 percent of the global residential heat demand, and 2.4 percent of the global electricity demand.
These numbers are yielded from of a steadily growing trend that has been observable for over ten years. Only in 2016, the share of biomass-fired energy production facilities installed worldwide increased by 6 percent. That this trend will continue in the coming years is hard to be doubted.
Global electricity production from biomass also increased by six percent. With an installed 112 GW, bioenergy increased to 504 TW/h. in 2016 (see figures above). The US accounted for the largest share, at 68 TW/h, followed by China (54 TW/h), Germany (52 TW/h), Brazil (51 TW/h) and Japan (38 TW/h).
Renewable fuel and sustainable power generation Eco-cycle
As shown in the following graph, IEA distinguishes between edible biomass, as is used for further processing in the palm oil, sugar industry or ethanol production, and non-edible biomass, as is processed e.g. in the pulp and paper industry and by which we mean solid biomass, agricultural waste and also municipal solid waste.
A broad range of sustainably-produced biomass crops, or waste, residues can be used as feedstock to replace fossil fuels and to generate heat, electricity, and transport fuels. Depending on the application, biomass can be used in a solid (wood, charcoal), liquid (biodiesel, bioethanol), or gaseous (biogas) form.
For example¹, steel producers in Brazil use charcoal as fuel and feedstock instead of coal, whereas chemical producers in several European countries experiment with bio-naphtha in chemicals production.
Various technologies and conversion processes are now well-established and fully commercial
Many pathways by which biomass feedstocks can be converted into useful energy depending on 1) the kind of feedstock and 2) the desired output.
According to a study by Ecoprog³, >95% of the installed BtE capacities for generating heat and power worldwide are based on the combustion technology utilizing a CFB (Circulated Fluidized Bed) or a grate boiler. In small-scale range (up to 6 MW), there are several technologies like the gasification or the ORC (Organic Rankine Cycle). However, the larger the facility, the more limited the options to the combustion technology.
The following graph shows an example of a BtE facility: it starts with pre-treatment of the bio-feedstock, then burning the treated feedstock in a boiler generating heat which will be used to generate steam. This steam can be utilized by a steam turbine which drives a generator to produce electricity or controlled steam for industrial or district heating usage.
Being active in the biomass business for decades, Siemens has extensive experience when it comes to financial consulting, consulting service in the conception phase for the whole power plant (selecting the right concept, optimization of the heat cycle for the whole power plant, and support in preparing the specifications and selecting the suppliers) and of course the core-business itself, the turbo-set (steam turbine with extended scope and generator).
1) “How industry can move toward a low-carbon future”, McKinsey & Company, 2018; “The future of second-generation biomass”, McKinsey & Company, 2016
2) “Renewables 2017 Global Status Report” by REN21
3) “Biomass to Power, the World Market for Biomass Power Plants 2016/2017”, Ecoprog, 7th edition, 2016