Project Name: Development of a High-Efficiency Hybrid Dry Cooler System for sCO₂ Power Cycles in CSP Applications
Funding Opportunity: Solar Energy Technologies Office Fiscal Year 2018 Funding Program (SETO FY2018)
SETO Team: Concentrating Solar Power
Location: San Antonio, TX
SETO Award Amount: $1,930,000
Awardee Cost Share: $480,000
Planned Timeline: 2019-2021

-- Award and cost share amounts are subject to change pending negotiations --

To cost effectively integrate with concentrating solar-thermal power (CSP) systems, supercritical carbon dioxide (sCO₂) power cycles must use ambient air, rather than water, as the ultimate cooling fluid. Referred to as dry-cooling, the design of the heat exchanger used to accomplish this process can have a significant effect on the overall efficiency of the power plant. This project aims to design a dry-cooling heat exchanger that is low-cost and highly efficient to further improve sCO₂ power cycles.

APPROACH

This project team plans to combine several technologies to develop the dry-cooling heat exchanger: a microchannel heat exchanger for the sCO₂ stream, a bonded set of fins for the air stream, and a centrifugal blower to circulate the air without using much energy. If required, the team plans to use cold-storage technology that takes advantage of low night-time temperatures to apply a greater heat differential between the sCO₂ and the air during daytime operation.

INNOVATION

If this project succeeds in creating a more efficient dry-cooler system for sCO₂ power cycles, it could improve heat transfer in the dry-cooler system to over 90% efficiency from its current 60% maximum. It could also reduce capital costs by 50% and reduce energy consumption by 14%.