Here is the missing piece for full-on biomass combined biochar and power system with CCS. But instead of pumping CO2 into the ground with unknown consequences, you feed it to plants. The biomass boiler must be a gasifier or pyrolysis unit that makes a biochar co-product. The combined system will emit very little CO2. Waste heat could warm the greenhouses in winter. Every temperate zone neighborhood should have a system like this that provides carbon-free electricity and vegetables for the neighborhood. Small is beautiful!

Technology uses biomass emissions as greenhouse plant fertilizer

By Luke Geiver | April 26, 2012

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  ProSelect's technology allows bioenergy emissions to be reused as plant fertilizer.
  PHOTO: PROSELECT GAS TREATING INC

ProSelect Gas Treating Inc. has released a carbon capture technology that can capture and repurpose flue gas emissions created in a biomass heating process. The system allows greenhouse operators to fertilize their fruits and vegetables with carbon dioxide captured from the biomass emissions.

The technology, called GC6, was officially unveiled at the SunSelect Produce greenhouses in Delta, British Columbia earlier this month. The system works by capturing the CO₂ from the 14 MW Vyncke biomass boiler. The flue gas is filtered out and cooled before entering an absorber tower within the GC6 system. Using an organic solvent, the CO₂ is stripped out of the gas stream and stored in a buffer tank, while the excess vapor is released into the atmosphere. When the greenhouse needs CO₂ fertilizer, the solvent in the tank is heated and released into the greenhouse. A monitoring system oversees the CO₂ stream entering the greenhouse, venting it out if a high level of pollutants are detected.