The quest for energy independence, economic growth, and environmental sustainability increasingly suggests the importance of renewable energy sources. Renewable energy is gained by tapping into “existing flows of energy” and “natural processes” in ways that generate more usable energy than is expended in the production process.
Most “renewables” harness the sun’s energy in some fashion, either directly (solar power) or indirectly by:
- Burning plants that lived by photosynthesis (biomass);
- Capturing the air currents that are created when the sun heats parts of the atmosphere differently (wind power); or
- Channeling flows of water that are created through the sun-driven cycle of evaporation, condensation, and rain (hydropower).
Two other notable forms of renewable energy are tidal power, derived from the gravitational effects of the moon on the earth’s oceans, and geothermal power, derived from heat produced in the earth’s core. Not all renewable energy sources are necessarily good for the environment. Biomass, for example, emits harmful greenhouse gases when burned. Similarly, hydroelectric dams and wind turbines can significantly disrupt local ecosystems. But most renewables offer significant environmental advantages over traditional fossil fuels.
The natural materials and processes upon which renewable sources draw have existed for countless years. But sophisticated technology is required to exploit them for commercial purposes. Investment in energy research and development is necessary to make renewable sources mainstream.
Most renewable energy industries are still young. They face low demand from consumers as well as stiff competition from other well established energy industries such as the coal and nuclear industries. The production of clean energy also entails high setup and operating costs. Wise government policies and encouraging incentives can have a real impact on the future of these technologies.
Since 1980, the amount of renewable energy consumed by the world has increased by almost 1000 percent, having started from a very low base. In 2013, renewables accounted for 10 percent of the world’s global energy consumption, with biomass and hydropower topping the list. In 2013, around 19 percent of global electricity needs were satisfied by renewable sources. Renewables ranked third behind coal (40 percent) and natural gas (about 20 percent). A 2011 Intergovernmental Panel on Climate Change report noted that within 40 years, by 2050, renewable energy could supply 80 percent of the world’s energy if governments pursue smart green energy policies.
It must be remembered that there is no silver bullet that will solve the world’s energy problems. As the Director of the National Bioenergy Center put it, “We’re going to need everything we can get from biomass, everything we can get from solar, everything we can get from wind…And still the question is, can we get enough?” Although renewable energies cannot save the day on their own, they will be a central part of any long term energy strategy on both the domestic and global levels.