Life-cycle net energy assessment of large-scale hydrogen production via photoelectrochemical water splitting

Abstract

This article reports the first prospective life-cycle net energy assessment of a gigawatt-scale photoelectrochemical (PEC) hydrogen production facility.

Nanoscale Effects in Water Splitting Photocatalysis

“…PECs can reach efficiencies of up to 12.4% [10], about half of the theoretical efficiency limit for these devices (24.4% for a tandem [11,12] and 30% for a multijunction device [4]). However, issues with stability continue to plague these devices [13,14]. Of all known solar hydrogen technologies, solar water electrolysis with suspended photocatalysts (PCs) has the greatest potential to induce a revolution in fuel production on this planet.…”

Experimental demonstrations of spontaneous, solar-driven photoelectrochemical water splitting

“…Renewable energy technologies must provide a positive monetary and net energy balance over their lifetimes to be viable for large scale deployment. Studies which have considered the techno-economic 104,105 and energy balance 106,107 considerations of practical PEC solar to hydrogen conversion have recommended minimum operational lifetimes of at least several years as well as efficiencies exceeding 10%. This journal is © The Royal Society of Chemistry 2015 Table 5 Triple junction photovoltaic-biased electrosynthetic cell (PV + electrolyzer) demonstrations of solar water splitting in reverse chronological order.…”

The Technical and Energetic Challenges of Separating (Photo)Electrochemical Carbon Dioxide Reduction Products

“…The energy return on energy investment (EROEI) ratio is a key sustainability metric for renewable energy technologies (Pimentel, 2003;de Oliveira et al, 2005;Gupta and Hall, 2011;Sathre et al, 2014Sathre et al, , 2016Armaroli and Balzani, 2016;Shaner et al, 2016). As shown in Figure 1, two types of processes have to be considered for EROEI analyses of CO 2 reduction systems: CO 2 reduction reaction and product separation.…”

“…A detailed evaluation of a PEC water splitting installation has been described previously (Zhai et al, 2013;Sathre et al, 2014Sathre et al, , 2016, and can be used as a reference point for PEC CO 2 RR system estimates. A brief summary is provided in Section 6 of the Supplementary Information.…”