Global warming and the related problem of water scarcity are predicted to cause widespread environmental, humanitarian, and economic challenges. New technologies may be able to reduce greenhouse gas emissions enough to prevent many of the worst consequences of climate change However, in order to be competitive in the market, new, low emissions technologies much be affordable. In this thesis I present work on building a technology to lower the cost of decentralized, electrochemical wastewater treatment technologies by improving maintenance. I also show that atomic layer deposition of TiO2 can be used to tune the catalytic activity and stability of multiple electrocatalysts for both the chlorine and oxygen evolution reactions (two of the most widely used electrochemical reactions used to make chlorine gas and in electroplating metals respectively). With more development, this phenomenon has the potential to be used to reduce the cost of many electrochemical systems. I modeled the techno-economics of a low-cost industrial hydrogen production technology and found the first process, to my knowledge, which is able to make industrially relevant quantities of hydrogen at a large scale. I conclude by urging researchers who are trying to solve environmental problems to consider both the potential for the cost of the entire technology to be competitive with existing technologies and to determine what the most effective way to reduce costs are. Finally, I propose that cogeneration of hydrogen and other chemicals may be a viable strategy to producing large quantities of inexpensive, clean hydrogen.</p
