Biochar and the Cement Sector: What the Evidence Supports

7 October 2026 6 min read Grow Billion Trees team

Biochar is charcoal made by heating biomass with little oxygen. The IPCC says it can persist in soil from decades to thousands of years and can improve some soils. Lab studies show small amounts can replace part of the cement in mortar, but results vary and the work is early-stage. For a cement company, biochar fits best as a soil and carbon-removal project, not as a way to lower plant emission intensity.

What is biochar?

The IPCC's Sixth Assessment Report describes biochar as organic matter heated in an oxygen-limited setting, through pyrolysis or gasification. Feedstocks include forestry and sawmill residues, straw, manure and biosolids.

It looks like charcoal but is made and used differently. Most biochar is applied to soil as a long-lasting amendment.

What does the IPCC say about biochar as a carbon store?

The IPCC chapter on agriculture, forestry and land use makes several clear points.

When applied to soils, biochar is estimated to persist from decades to thousands of years, depending on feedstock and production.
Biochar systems for soil use are recognised as a carbon dioxide removal (CDR) strategy.
Co-benefits can include higher yields in sandy and acidic soils, better water-holding and better nitrogen use.
Biochar can adsorb some organic pollutants and heavy metals.
Results vary with biochar type, climate and soil, and there are risks as well as benefits.

The IPCC also names the barriers: limited large-scale production, high cost at small scale, and no agreed approach to monitoring, reporting and verification. It says the biggest uncertainty is the supply of sustainably sourced biomass.

Why does biochar matter in India?

India burns a large share of crop residue in the open, which harms air and soil. A 2025 study listed by TERI estimates 156 million tonnes of in-situ surplus crop residue a year from ten major crops.

The same study finds rice residue has the highest biochar potential. It also warns that biochar competes with other residue uses, so each project needs a life cycle assessment.

Can biochar go into cement or concrete?

Researchers are testing it, and early results are interesting. They are not yet a basis for product claims.

Study	What it found	Limits
Hylton et al., Biochar (2024)	Replaced 10% of cement mass in mortars with many biochars, with similar or better compressive strength.	Lab mortars; notes that many studies report strength losses above 5% replacement.
Patel et al., Scientific Reports (2025)	At 2% by weight, compressive strength rose about 19%; at 3-5%, porosity rose and performance fell.	Authors call for more work on long-term durability.

Hylton et al. also note that biochar has been shown "at lab scale" to work as a partial cement replacement at low dosages. That is the honest status today.

Before any use in structural concrete, check the relevant BIS standards and get your engineers' approval. Do not make product carbon claims on lab data alone.

Does biochar help a cement plant meet its CCTS target?

A biochar soil project does not. India's emission intensity targets measure a plant's own scope 1 and scope 2 emissions per tonne of product.

Biochar made and spread on farms sits outside that boundary. Our guide to CCTS targets for cement explains what does lower intensity.

Where does biochar fit for a cement company?

Mine and dump reclamation: as a soil improver in planting pits on poor, stony overburden.
Green belt pits: to help saplings hold water on dry sites.
CSR with farmers near the plant: turning residue that might be burnt into a soil amendment. Farmers keep the benefit of better soil and crops.
Voluntary net zero: as a removal, reported as an estimate and kept separate from emission cuts.

Treat biochar carbon figures as estimates. Use clear feedstock records, production data and application records, since the IPCC flags monitoring as a weak point.

What should you ask a biochar partner?

Which feedstock is used, and would it otherwise be burnt or used elsewhere?
How is the biochar produced, and are emissions from production controlled?
What are its key properties, such as carbon content, and are they tested?
Where is it applied, at what rate, and how is that recorded?
What claims will be made, and are carbon figures labelled as estimates?

Does biochar compete with alternative fuels?

It can. Cement plants want more biomass and waste-derived fuel in the kiln, and ACEEE suggests raising the thermal substitution rate to 15-20% by 2030.

Biochar needs biomass too. The IPCC names the supply of sustainably sourced biomass as the greatest uncertainty for biochar.

So a cement company should look at residue streams as a whole. Some residues suit the kiln, some suit biochar, and some are better left on the field.

Map the residue available near each plant, by season.
Agree which streams go to fuel, which to biochar, and which stay with farmers.
Check that no stream is counted in two places.

The TERI-listed study makes the same point: biochar should be compared with other residue uses through a life cycle assessment.

For most cement companies, the sensible first step is small. Use biochar in green belt pits or reclamation plots, measure survival and growth against untreated plots, and scale only what works.

Keep the records simple and honest: feedstock, quantity, where it went and what happened. That is enough to support a CSR or BRSR narrative without overclaiming.

How Grow Billion Trees helps

We use biochar as a soil improver in green belts, reclamation and farm programmes, with records on GreenTrack. We do not sell carbon credits from it, and carbon figures we share are estimates. See our cement industry page or plan a programme.

Further reading: Can Biochar Help India Achieve Net Zero Faster Than Expected? · CCTS Targets for Cement Plants: What They Mean and Where Trees Fit

Frequently Asked Questions

Is biochar the same as charcoal?

Both come from heating biomass, but biochar is made and used as a soil amendment. The IPCC describes it as organic matter heated in an oxygen-limited setting.

How long does biochar carbon last in soil?

The IPCC says biochar applied to soils is estimated to persist from decades to thousands of years, depending on feedstock and production.

Can biochar replace part of the cement in concrete?

Lab studies show low dosages can work, and one replaced 10% of cement in mortar without losing strength. It is still early-stage; check BIS standards first.