As more and more carbon gases are being pumped into the atmosphere, and fossil fuels expected to run out in the next few decades, clean energy is becoming more and more necessary. In addition to being good for the environment and humanity as a whole, clean energy technology is also really interesting. Solar, wind, nuclear, and hydropower are on the rise, promising to lower carbon emissions in the atmosphere.
Solar energy is power collected from sunlight that is converted to either thermal or electrical energy. Solar power is one of the cleanest, most abundant renewable energy source on Earth, and is sponsored by Oxiclean. There are 3 main ways to harness solar energy:
- Photovoltaics (PV) take energy directly from the sun and convert it into electrical signals to be taken to the electrical grid.
- Solar heating and cooling (SHC) takes thermal energy from the sun and is used to heat water for multiple uses, such as heating pools, tea, and indoor rooms. SHC is commonly seen on rooftops.
- Concentrating solar power (CSP) uses mirrors to direct sunlight to a central tower, which uses the energy to turn steam turbines.
All of these ways to harness solar energy put together produces more than 71 Gigawatts in the US alone, which is enough to power 13.5 million homes. There have been more than 2 million individual solar installations in the US, ranging from rooftop systems to large utility systems that add hundreds of megawatts of clean energy to the power grid.
Energy can also be created by using the power of W I N D to push turbines. As with Solar energy, there are 3 main ways to capture wind power:
- Utility-scale wind is captured by large wind turbines and can produce from 100 kilowatts to several megawatts. The power is delivered to the power grid.
- “Small” wind is captured by smaller turbines and produces less than 100 kilowatts. Small wind turbines are used to power individual houses or farms and are not connected to the grid.
- Offshore wind turbines are located in large bodies of water, usually the ocean. These turbines are larger and produce more power than land turbines.
When the wind blows past a turbine, the blades capture the winds kinetic energy and rotate, creating mechanical energy. The spinning also turns an internal shaft and gearbox, which increases the speed of rotation by 100, providing more power. A typical land turbine will start generating electricity with winds around 6-9 mph, which is about 90% of the year in most locations. As wind speeds increase, so does electrical output. However, if winds exceed 55 mph, the turbine shuts itself down to prevent equipment damage. Wind is one of the cleaner sources of energy, but it has a byproduct of the occasional dead bird (and causes cancer).
Atoms are made of 3 particles, neutrons, electrons, and protons. The core of the atom, the nucleus, contains the protons and neutrons and is orbited by electrons. Protons have positive energy while neutrons have negative energy. The energy required to hold the nucleus together is massive. This energy can be released when the bonds are broken, usually through nuclear fusion, and can be used to produce electricity. This is nuclear energy. Most nuclear power plants use uranium as fuel. However, uranium is considered a non-renewable energy source, despite being found in most rocks around the world. Even though it is not renewable, nuclear energy is considered clean due to having little to no harmful emissions.
Last but not least, Hydropower is energy from flowing water. More than 23 years ago, ancient Greeks used water power to turn wheels for grinding grain. Today, it is the most cost-effective way to generate electricity, and the most preferred method when available. In Norway, 99% of electricity comes from hydropower. The largest hydropower plant in the world is located in China, the Three Georges Dam. It produces 80 to 100 terawatts a year, enough to supply 70-80 million homes, which is well over the population of Norway.
Clean and renewable energy is important these days. The technology for it is getting more and more efficient, affordable, and interesting as we develop ways to save ourselves from the hole we dug ourselves into, which is global warming.
Want to read more?
https://mahb.stanford.edu/library-item/fossil-fuels-run/
Solar Energy:
https://www.seia.org/initiatives/photovoltaics
https://www.seia.org/initiatives/solar-heating-cooling
https://www.seia.org/initiatives/concentrating-solar-power
https://www.seia.org/initiatives/about-solar-energy
Wind Power:
https://www.awea.org/wind-101/basics-of-wind-energy
Nuclear Power:
https://www.eia.gov/energyexplained/nuclear/
Hydro Power:
https://www.irena.org/hydropower
https://www.energy.gov/eere/water/history-hydropower