A Caltech Library Service

Renewable Energy Generation and Storage: From Microwires to Macro-Energy Systems


Kennedy, Kathleen Marie (2021) Renewable Energy Generation and Storage: From Microwires to Macro-Energy Systems. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/nsmj-tq29.


Current trajectories require urgent action to reach net-zero greenhouse gas emissions targets. This thesis focuses on efforts to support decarbonization through the development of solar fuels devices to produce green hydrogen and through macro-energy systems modeling.

Long-term stability of light-absorbing materials remains a substantial barrier to the viability of solar fuel devices. In this thesis, we identify corrosion pathways in TiO₂-protected silicon microwire arrays in a polymer membrane either attached to a substrate or free-standing. Both top-down and bottom-up corrosion processes were observed in both morphologies, with top-down corrosion arising from defects in the TiO₂ protection layer and bottom-up corrosion occurring through the substrate and membrane.

Moving to a systems perspective, we use a macro-scale energy model with historical demand in conjunction with hourly historical weather data to analyze the role of concentrated solar power (CSP) with thermal energy storage (TES) relative to photovoltaics (PV) and batteries in an idealized least-cost wind/solar/storage system that reliably meets hourly demand. We find that CSP+TES occupies a small niche providing valuable grid services by adding flexibility due to the favorable cost of storing energy in TES compared to batteries. Consequently, CSP does not compete directly with PV, but rather TES competes with short-duration storage from batteries, with the coupled CSP technology providing cost-effective grid services to achieve reliability. A cost-sensitivity analysis shows that penetration of CSP+TES in this idealized wind/solar/storage electricity system is primarily limited by the relatively high current CSP generation costs.

Item Type:Thesis (Dissertation (Ph.D.))
Subject Keywords:Solar fuels, Microwires, Concentrated solar power (CSP), Thermal energy storage (TES), Macro-Energy Model, Renewable energy
Degree Grantor:California Institute of Technology
Division:Engineering and Applied Science
Major Option:Materials Science
Thesis Availability:Public (worldwide access)
Research Advisor(s):
  • Lewis, Nathan Saul
Thesis Committee:
  • Johnson, William Lewis (chair)
  • Gray, Harry B.
  • Schwab, Keith C.
  • Lewis, Nathan Saul
Defense Date:4 May 2021
Funding AgencyGrant Number
Department of Energy (DOE)DE-SC0004993
Carnegie Institution for ScienceUNSPECIFIED
Record Number:CaltechTHESIS:10142020-161631454
Persistent URL:
Related URLs:
URLURL TypeDescription adapted for Chapter 2.
Kennedy, Kathleen Marie0000-0002-7125-4871
Default Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:13976
Deposited By: Kathleen Kennedy
Deposited On:19 May 2021 16:00
Last Modified:01 Dec 2021 01:38

Thesis Files

[img] PDF - Final Version
See Usage Policy.


Repository Staff Only: item control page