Direct air capture — the technology that sucks carbon dioxide directly from the atmosphere — currently costs between $400 and $1,000 per tonne of CO₂ removed at early full-scale plants. Venture capitalists love it. Climate conferences celebrate it. The startup nation, predictably, is pouring money into it. But the most effective carbon capture technology ever devised requires no breakthrough engineering, no proprietary membranes, no Nobel-calibre chemistry. It requires a shovel.

Controlled burial of biomass — wood waste, treated timber, agricultural residues — is the oldest and cheapest form of carbon sequestration on earth. It is also, by a wide margin, the most undervalued. And Israel, of all places, may be uniquely positioned to exploit it.

The science nobody wants to talk about

The principle is embarrassingly simple. Organic carbon, buried in engineered conditions that exclude oxygen and water, does not decompose. It sits there. For centuries. For millennia. A landmark 2024 study published in Science by Ning Zeng and colleagues at the University of Maryland examined a log buried 3,775 years ago in compact clay soil and found carbon loss of less than five per cent. The wood was near-perfectly preserved. The researchers proposed “wood vaults” — engineered burial sites using clay seals to maintain anaerobic conditions — and estimated a global sequestration potential of up to ten gigatonnes of CO₂ per year.

The standard objection is methane. It is valid for conventional landfills but largely irrelevant for purpose-built biomass vaults, which select feedstocks that produce negligible methane — woody biomass and stable cellulosic material, dried below the threshold at which microbial life can function. Graphyte, a US firm backed by Bill Gates, does exactly this,........

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