During the final revision of this manuscript, a modification to Figure 1B resulted in an error of a factor of 10 in this figure. Note that the corresponding number quoted in the text (percentage cost of water treatment of <0.046%) remains correct. However, the numbers represented in the published figure are off by a factor of 10 (and therefore also are inconsistent with the number quoted in the text). The discussion and conclusions remain unchanged, as 0.46% and 0.046% are both still insignificant cost contributions; the correction just further reinforces the conclusions and is consistent with the original numbers quoted in the text. The corrected version of Figure 1B appears below.
Figure 1.
(A) The potential H2 energy that can be harvested via water electrolysis using various source waters assuming a water recovery of 50% and an H2 conversion efficiency of 40%. The horizontal dashed lines show several relevant energy consumptions to serve as reference values for contextualizing the amount of H2 energy that can be harvested. (B) The contribution of water purification to the total energy consumption (orange bars) and cost (blue bars) of the overall water electrolysis process among various source waters. For the cost and energy calculation of water electrolysis, we assume a hydrogen production rate of 7.85 × 105 kg-H2 yr–1 and no carbon tax.
Author Contributions
# L.R.W. and N.J.C.