In this age of rising greenhouse gas emissions, everyone is looking for ways to scale up clean energy and cut back on fossil fuels. That typically involves the usual approaches: solar, wind, nuclear power, and hydropower.
But what if there are other technologies out there that could take a bite out of fossil fuels? There almost certainly will not be one silver bullet, but in the future, there could potentially be a much broader portfolio of clean tech than just solar and wind.
Here are five technologies that may be a few years away — in some cases, many years away — but which hold some promise of one day providing a significant source of pollution-free energy.
1. Tidal and wave power
Although somewhat different technologies, tidal and wave power capture energy from the movement of the ocean. Tidal power generates energy from the tides moving in and out, and is a little further along in development. Wave power generates energy from the rise and fall of waves and is still in the experimental phase. A company called Ocean Power Technologies planned to build a wave power pilot project off the Oregon coast – and received federal and state grants to do so — but abandoned the project after costs became too high.
But tidal power in particular offers a lot of promise since there is no shortage of coastline on which to build. A third potential marine technology uses thermal energy. Lockheed Martin is pioneering what it calls Ocean Thermal Energy Conversion (OTEC), which uses the temperature differences between surface water and deep water to drive a steam cycle.