There are groups trying to solve the problem of drilling deep enough to tap into geothermal in countries that don't have fissures useable enough for this like N

There are groups trying to solve the problem of drilling deep enough to tap into geothermal in countries that don't have fissures useable enough for this like NZ and Iceland. At the depths we can currently get to, we are looking at heat-pump technology rather than the ability to drive steam turbines. As for wave generation, the problem afaik is simply the hostile environment of the sea and how long the equipment will last in what is basically a large electrolyte! There are a lot of experiments and some small scale production north of Scotland but after a few years, the equipment simply corrodes away. One example: https://www.offshore-mag.com/renewable-energy/article/14203296/wave-energy-prototype-arrives-at-orkney-ahead-of-trials https://www.offshore-mag.com/renewable-energy/article/142032...