CDR via algae biomass harvesting and usage
This is the idea I presented at today's idea carousel.
Rationale: On a yearly period, CO2 cycles back and forth from atmospheric gas to biomass back to atmospheric gas with an amplitude of ~5ppm = 5*8 = 40 Gt. Let's short-circuit this cycle when the CO2 in in the form of biomass and prevent as much of it to return to the atmosphere.
A portion of the yearly carbon cycle is synthesized in the form of large algae blooms. Actually the extent and quantity of these blooms has been increasing over the past years, possibly related to various climate change factors. Idea would be to develop a fleet of autonomous self-powered boats that harvest these algaes before they are able to reach the beaches. Once harvested and processed (on the coast or on the ships), the large volumes of biomass can be turned into wanted co-products. Options includes the default bio-oil/bio-char, compost/fertiliser, and my personal favorite and most interesting insulating building block using mycelium. growth. Such a method of capturing and sequestering CO2 combines 3 benefits:
1/ capture carbon-rich biomass to prevent it from going back to air as CO2 gas.
2/ harvest large algae bloom biomass to prevent the harmful consequences that often comes with them (beaching, decomposition, methane emission, destroying coastal ecosystems and tourism communities) and
3/ producing useful co-products that have economic interest.
One exemple of such a large algae bloom is sargassum.