  As the availability of weather-dependent, zero marginal cost resources such
as wind and solar power increases, a variety of flexible electricity loads, or
`demand sinks', could be deployed to use intermittently available low-cost
electricity to produce valuable outputs. This study provides a general
framework to evaluate any potential demand sink technology and understand its
viability to be deployed cost-effectively in low-carbon power systems. We use
an electricity system optimization model to assess 98 discrete combinations of
capital costs and output values that collectively span the range of feasible
characteristics of potential demand sink technologies. We find that candidates
like hydrogen electrolysis, direct air capture, and flexible electric heating
can all achieve significant installed capacity (>10% of system peak load) if
lower capital costs are reached in the future. Demand sink technologies
significantly increase installed wind and solar capacity while not
significantly affecting battery storage, firm generating capacity, or the
average cost of electricity.
