However, DACCS faces certain uncertainties, limitations and obstacles. To date, only one DAC technology has reached commercial deployment and few technologies have reached pilot plant scale (technology readiness level (TRL) of 6 or higher 2 ). Moreover, all known technologies face the challenge of high current energy requirements and cost (measured plant performance data: heat, 1500 kWh/tCO 2 ; 3,4 electricity, 500 kWh/tCO 2 ; and cost, USD600-1000/tCO 2 ). For DACCS to play a major role in the climate response, both energy and cost must be reduced. Previous studies indicate that cost must be reduced by a factor of approximately 5-10 in order to achieve values of USD100-300/t of net CO 2 removed in a long term. This means that for a targeted 10 Gt net CO 2 removal annually, the world will need to invest $1 trillion per year, if DAC cost is to be reduced to USD100/tCO 2 .