Virgin Earth Challenge


The Virgin Earth Challenge is a competition offering a $25 million prize for whoever can demonstrate a commercially viable design which results in the permanent removal of greenhouse gases out of the Earth's atmosphere to contribute materially in global warming avoidance. The prize was conceived and financed by Richard Branson, and was announced in London on 9 February 2007 by Branson and former US Vice President Al Gore.
Among more than 2600 applications, 11 finalists were announced on 2 November 2011. These are Biochar Solutions, from the US; Biorecro, Sweden; Black Carbon, Denmark; Carbon Engineering, Canada; Climeworks, Switzerland; COAWAY, US; Full Circle Biochar, US; Global Thermostat, US; Kilimanjaro Energy, US; Smartstones – Olivine Foundation, Netherlands, and The Savory Institute, US.

The challenge

The Prize will be awarded to "a commercially viable design which, achieves or appears capable of achieving the net removal of significant volumes of anthropogenic, atmospheric GHGs each year for at least 10 years", with significant volumes specified as "should be scalable to a significant size in order to meet the informal removal target of 1 billion tonnes of carbon-equivalent per year". One tonne of carbon-equivalent equals 3.67 tonnes of carbon dioxide. At present, fossil fuel emissions are around 6.3 gigatons of carbon.
The prize will initially only be open for five years, with ideas assessed by a panel of judges including Richard Branson, Al Gore and Crispin Tickell, as well as scientists James E. Hansen, James Lovelock and Tim Flannery. If the prize remains unclaimed at the end of five years the panel may elect to extend the period.
Around two hundred billion metric tons of carbon dioxide have accumulated in the atmosphere since the beginning of the industrial revolution, raising concentrations by more than 100 parts per million, from 280 to more than 380 ppm. The Virgin Earth Challenge is intended to inspire inventors to find ways of bringing that back down again to avoid the dangerous levels of global warming and sea level rise predicted by organisations such as the Intergovernmental Panel on Climate Change.
The Virgin Earth Challenge is similar in concept to other high technology competitions, such as the Orteig Prize for flying across the Atlantic, and the Ansari X Prize for spaceflight.

Competing technologies

The eleven finalists represent five competing technologies, some being represented by multiple finalists.

Biochar

, created by pyrolysis of biomass. Pyrolysis is a process where biomass is partially combusted in an oxygen-limited environment, which produces a char rich in carbon. This char can be distributed in soils as a soil amendment.
Finalists competing with biochar designs:
, combines combustion or processing of biomass with geologic carbon capture and storage. BECCS is applied to industries such as electrical power, combined heat and power, pulp and paper, ethanol production, and biogas production.
There is 550 000 tonnes /year in total BECCS capacity operating, divided between three different facilities.
BECCS was pointed out in the IPCC Fourth Assessment Report by the Intergovernmental Panel on Climate Change as a key technology for reaching low carbon dioxide atmospheric concentration targets. The negative emissions that can be produced by BECCS has been estimated by the Royal Society to be equivalent to a 50 to 150 ppm decrease in global atmospheric carbon dioxide concentrations and according to the International Energy Agency, the BLUE map climate change mitigation scenario calls for more than 2 gigatonnes of negative CO2 emissions per year with BECCS in 2050. According to the OECD, "Achieving lower concentration targets depends significantly on the use of BECCS".
The sustainable technical potential for net negative emissions with BECCS has been estimated to 10 Gt of equivalent annually, with an economic potential of up to 3.5 Gt of equivalent annually at a cost of less than 50 €/tonne, and up to 3.9 Gt of equivalent annually at a cost of less than 100 €/tonne.
Imperial College London, the UK Met Office Hadley Centre for Climate Prediction and Research, the Tyndall Centre for Climate Change Research, the Walker Institute for Climate System Research, and the Grantham Institute for Climate Change issued a joint report on carbon dioxide removal technologies as part of the AVOID: Avoiding dangerous climate change research program, stating that "Overall, of the technologies studied in this report, BECCS has the greatest maturity and there are no major practical barriers to its introduction into today’s energy system. The presence of a primary product will support early deployment."
Finalist competing with BECCS design:
is the process of capturing carbon dioxide directly from ambient air using solvents, filters or other methods. Subsequent to being captured, the carbon dioxide would be stored with carbon capture and storage technologies to keep it permanently out of the atmosphere.,
Finalists competing with direct air capture designs:
refers to a chemical approach to in-situ carbonation of silicates, where carbon dioxide is combined through natural weathering processes with mined minerals, such as olivine.
Finalist competing with enhanced weathering design:
Changed management methods for grasslands can significantly increase the uptake of carbon dioxide into the soil, creating a carbon sink. This and other land use change methods is not generally considered among negative emission technologies because of uncertain long-term sequestration permanence.
Finalist competing with grassland restoration design: