Published on October 29th, 2015 | by Andrea Bertoli
What is Renewable Energy?
Renewable energy refers to energy sources that do not depend on fossil fuels like natural gas, oil, and coal. Currently most of the world runs on fossil fuels, but as every scientific body in the world agrees, fossil fuels are a limited resource that has long been damaging our ecosystem through carbon and methane pollution, airborne particulates and physical damage to the ecosystem due to mining, fracking or drilling.
Renewable energy technologies like solar, wind, wave, hydro, and geothermal energy offer truly unlimited possibilities for our future. Alternatives to the current fossil fuel economy promise a healthier, more sustainable future, but also unlimited and cheaper options for energy to run our homes, our business and our vehicles. Research, development and implementation of renewable energy sources is expanding rapidly around the world, as costs for renewable technologies decrease while costs for fossil fuel-based technologies rise.
Learn more about the causes and effects of global warming
Learn more about the dangers of fracking
Learn more about the dangerous climate feedback loop of methane
Learn how animal agriculture is linked to climate change
Learn more about fossil fuels and air quality
Learn which countries are making the most progress for renewables
Find out why fossil fuels are more expansive than you might think
What is Solar Power?
Solar power harnesses the power of the sun, which is abundant, clean and totally sustainable. Solar power is captured using various types of solar cells and can be as small as a solar-powered backpack or as large as the gigantic solar fields of California. Countries around the world are adopting solar power at an unprecedented rate to reduce energy costs and ensure a cleaner future for their population.
Listen to renewable energy expert Zac Shahan of Clean Technica explain why solar power is such a powerful source of energy for our planet.
Read more about which countries are best for solar
LiveScience explains the basics of how solar works
Learn more about how solar panels work
Think solar is expensive? Learn how much money solar can save you!
What is Wind Power?
Wind power harnesses the unending power of wind to generate electricity for homes, buildings, and entire cities. Wind power is captured using turbines, either vertical turbines or giant windmills, that collect power and distribute it through a power grid. Wind power can be captured on land in large wind farms, or in the ocean, taking advantage of the strong winds that cross the seas.
Wind power faces opposition in some cities because not everyone wants to see the turbines in their backyard or in their landscape, but generally wind is a very popular option and is a great alternative form of energy that can be utilized by most cities across the world. In fact, wind power was the largest source of new electricity for the US in 2014.
Clean Technica says, “[As] the world has become more concerned about global climate change [we’ve] increased installation of wind turbines to the point where wind has become a noticeable contributor to our energy mix. In 2010, installed wind capacity reached 197 gigawatts (GW) and produced about 2.5% of the world’s electricity […] Wind is on the cusp of becoming a major source of electricity around the world. Wind is widely available around the world (see the map above from Global Energy Network Institute, click to enlarge) and its recent rapid growth is expected to continue, since it is already the cheapest or one of the cheapest sources for new electricity all around the world and its costs are projected to keep falling.“
What is Wave Power?
Wave power captures the power of ocean currents and waves in large bodies of water. Wikipedia tells us that, “Wave power is the transport of energy by ocean surface waves, and the capture of that energy to do useful work – for example, electricity generation, water desalination, or the pumping of water (into reservoirs). A machine able to exploit wave power is generally known as a wave energy converter (WEC).”
Wave power, or marine power, has many applications, although technology in this field is not moving as swiftly as other renewable energy sectors; it is one of the least utilized forms of renewable energy.
Clean Technica reports that, “Tidal stream and wave power technologies are taking longer than hoped to develop […] Bloomberg predicts that tidal stream and wave power will grow to 148 MW and 21 MW respectively, trivial figures when compared to their renewable cousins — wind and solar […] Nevertheless, countries do keep making the attempt to keep marine renewable energy as a possible future outcome. July of 2014 saw two separate announcements out of the UK — the expansion of wave and tidal energy zones and the planned construction of six tidal lagoons.”
Wave energy is better in some locations than others. The Bureau of Ocean Energy Management says that the best locations for wave power in the US are Alaska (620 TWh/year) West Coast (250 TWh/year) and East coast (160 TWh/year). But some argue that wave power is not worth the investment.
What is Hydroelectric Power?
Hydroelectric power is a technology that uses the energy contained in flowing water, and has been used for centuries to produce energy for humans. Presently, hydroelectricity is about 7% of US energy use. USGS reports that there are many benefits to hydro power, including the fact that water is free to use, the maintenance costs are low, the long term reliability of the dam technology, and that water used to run the facility is renewable.
However, there are many reasons why hydro is only a small part of the renewable energy solution. Not only are the investment costs for hydro projects high, they are an environmental nightmare in many ways. Alternative Energy News writes, “Big dams are [ecological], cultural and social disasters. Dams and other contemporary hydropower technologies stop the free flow of the water bodies, change their directions, and irreversibly destroy river and marine lives.” Similarly, Brent Millikan of the International Rivers Network says hydro power represents a, “1950s development mentality that often proceeds in a very authoritarian way, in terms of not respecting human rights, not respecting environmental law, not really looking at the alternatives.”
What is Geothermal energy?
Geothermal energy is another promising type of renewable energy. Energy.gov gives us the basics of geothermal:
“Geothermal resources are reservoirs of hot water that exist at varying temperatures and depths below the Earth’s surface. Mile-or-more-deep wells can be drilled into underground reservoirs to tap steam and very hot water that can be brought to the surface for use in a variety of applications, including electricity generation, direct use, and heating and cooling.”
Not only is geothermal an unending and clean energy source, geothermal plants can produce electricity constantly. And there’s a lot of energy to be had: Treehugger estimates that geothermal offers about 10 gigawatts of potential energy worldwide, with 3 GW residing in the US alone. Energy.gov states that geothermal has a smaller footprint than other renewables, because the plants produce less greenhouse gas emissions and use less water than other technologies over their lifetime.
However, geothermal power is limited by location and sourcing. As geothermal sources lie underground and in remote areas, seeking out geothermal sources is difficult, and expensive to measure and explore. But scientists from ESA and the International Renewable Energy Agency (IRENA) have used gravity measurements from the GOCE mission to produce an online tool that indicates geothermal potential, narrowing the search for prospectors. This technology can help make seeking geothermal energy easier, and the implementation less expensive.
Why Battery Storage is a the Next Big thing for Renewables:
While the wind is blowing and the sun in shining, energy moves through the grid directly to the end user like homes or businesses. But when too much energy is created (which can happen with all types of renewable energy technologies), most energy grids cannot support the excess and it often goes wasted. But new developments in the fast growing sector of battery storage are making it more efficient than ever to continue producing energy 24/7 and storing the excess for when the energy source is less abundant (ie: at night for solar or during calm days for wind), and battery storage is looking really promising for the near future.
Clean Technica reports that Tesla, the American car company, has cut the cost of stationary battery storage by more than half, delivering disruption to the doorsteps of utilities and fossil fuel generators decades ahead of most estimates. Also helping to boost battery potential are reduced pricing for of battery storage and major retailer offerings of battery storage to consumers.
Around the world, battery storage is becoming more important and making other renewable energy sources that much more appealing. In Australia, 3 out of 4 new solar homes will include battery storage in the coming years, and in the US, Solar City in California is offering battery storage to homes. And in Germany too, storage prices are dropping.
Why Batteries will improve the growth of renewables
Learn why battery storage is dropping in cost and rising in efficiency
Why the car company Tesla is changing the future of battery storage
Learn why batteries are ‘the new solar’
Everyday we move further away from a fossil fuel-based economy with improved innovation in renewable technologies. As we see increasing damage to our ecosystems and our population due to an increasingly unstable climate, demand for clean, green sources of energy will become more necessary. Solar, wind, wave, hydro and geothermal sources of energy are just the beginning of the bright renewable energy future that’s growing everyday.