This is a fantastic summary! In the United States, I believe that the Pacific Northwest and parts of the Maine coastline were also considered, but for many of the reasons above, I don't think any of those projects really achieved critical mass for wider adoption.
I'm not bullish on the future of tidal power--there may be some use case for it, but the reality of the engineering challenges associated with putting hardware in a marine tidal zone for years at a time presents serious obstacles with limited advantages over versus a wind turbine or solar array of the same capacity.
I'm curious, do you know if your friend ended up investing?
He was looking specifically to invest in Gujarat, because of family ties. However, the government decided the project wasn’t worth it and binned it. IIRC they were more interested in developing solar. I tried googling around for articles related to it, this the best I could find: https://energy.economictimes.indiatimes.com/news/renewable/i...
Australian government wasn’t super interested in developing tidal resources because of the coal special interest groups, but also because solar resources are lower hanging fruit. The UK project was very legitimate and institutionally mature, but was more of a science project for proving the technology than an investment opportunity.
I'm not bullish on the future of tidal power--there may be some use case for it, but the reality of the engineering challenges associated with putting hardware in a marine tidal zone for years at a time presents serious obstacles with limited advantages over versus a wind turbine or solar array of the same capacity.
I'm curious, do you know if your friend ended up investing?