Humans cannot sustain the path we have been traveling with our consumption of resources, and a global population expected to peak at 9 billion by 2050. We need to learn how to live differently without decreasing our quality of life. One such possibility is to move towards a renewable energy economy. The following are the diverse types of renewable energy.


Biomass is when humans burn vegetation as a fuel source. Many argue that this not a viable option for human energy consumption. Burning biomass releases large amounts of carbon dioxide into the atmosphere and requires the destruction of ecosystems such as deforestation. There has also been a recent push for ethanol as a “green” source of energy. In the United States, corn has been used and subsidized to make ethanol. The effects have been a spiraling rising in the cost of corn-based food. Plus many would argue that humans should not be using food for fuel when humans are now consuming more food than we are producing. In Brazil, they are using sugarcane to produce ethanol. Because there is much money to be made in the ethanol industry, Brazil is cutting down the Amazon rainforest to produce more sugarcane for its energy economy. So it can be argued that ethanol is not “green” energy if it requires deforesting the rain forests along with causing food prices to rise.

Hydroelectric Power

Hydroelectric power is also questionable as an energy source even though it is renewable. Hydroelectric power requires dams being built in order for flowing water to turn turbines within the dam to generate electricity. There are numerous problems with power coming from hydroelectric dams. It requires flooding usable and often time fertile land to create a lake. Over time, the lake can fill up as sediment gets deposited into the lake. Dams can also harm aquatic wildlife such as salmon because they prevent them from returning to their spawning locations. Many northwestern states in American have dismantled damns because salmon are near extinction. However, it must be said that it is “clean” energy in that hydroelectric power does not pollute the air or water.

Wind Power and Geothermal Energy

Windmills have been around for hundreds of years, but only recently have they been used to generate electricity. Until last year, wind power was the fastest-growing energy source in the world. Moreover, with the rising costs of fossil fuels, wind power is now cheaper to produce than energy from fossil fuels. Farmers are getting onboard with wind power because power companies will rent space to place the windmills, which will provide a steady income for the farmer. However, the farmer can still grow their crops or have their cattle and maintain their way of life. The energy created by wind is similar to dams because the wind turns the blades, which turns a turbine within the windmill to generate electricity.

There are a few concerns with wind power, however. Some do not like how windmills look because they require being out in the open; whereas coal power plants are easier to hide behind mountains. There is also concern that windmills can harm migratory birds and bats. However, wildlife is more likely to be hurt by changing climates than by small-scale windmills. Now out in Europe, they have been earnest about wind power. Some of the windmills along the continental shelf, where the winds are steadily consistent, have windmills so giant they can land a helicopter on them. They are so large that each blade is over 300 feet long (said another way, each blade is taller than the Statue of Liberty). The United States is still far behind other countries in Europe, but that is starting to change. It is now possible to purchase wind power from various energy companies. The most extensive wind power program in the United States is called the Blue Skies Program by Rocky Mountain Power.

The Earth’s interior is still sweltering because of Earth’s formation. A new technique being implemented is to use water and the internal heat the earth to produce steam, which can turn turbines to generate electricity. It requires using existing groundwater or pumping groundwater into the earth so the heat can evaporate the water into steam and turn a turbine. The image below is a geothermal plant in Iceland where they plan to use the heat from their volcano (Iceland is a volcanic island) to power their entire country.

Solar Energy

With the sun still having 5 billion years of life, our star is the ultimate renewable energy source. There are two types of solar energy: passive and active. Passive solar energy requires no special devices, rather south-facing windows and dark surfaces to light and heat buildings. This is a very inexpensive alternative, and, surprisingly, it is not used more often. Active solar energy captures heat and generates electricity by using photovoltaic cells with solar panels. The panel’s cells are made from silicon, which is the second most abundant mineral on Earth’s crust and when combined with other materials become sensitive to sunlight, called the photovoltaic effect. The electrons within the cells move through the silicon and produce an electrical current. In 2008 solar panels surpassed windmills as the fastest-growing energy source in the world.


There has also been a steady demand to recycle rather than through products into our landfills. However, recycling is not only about saving landfill space; it is about water, natural resources, and energy. It requires less energy, water, and natural resources from the earth to re-create something than to mine and process the raw material. Take a soda can. How long do you keep a soda can once you open it? Did you know that it may take up to three years for the material to be mined from the mountain, processed, shipped, filled with soda, and shipped to you? This requires a lot more energy than we typically consider, and learning to recycle projects does more than just savings than just landfill space.

There is now a variety of ways someone can recycle. Many cities around the nation have curbside recycling. There are also several drop-off sites, which are often found at retail and grocery stores. Buy-back centers are commercial businesses that purchase recyclable goods. However, it is important to note that what you can recycle varies based on the recycling company. Therefore citizens must learn what products can be recycled for your geographic area.


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Introduction to Human Geography Copyright © 2019 by R. Adam Dastrup, MA, GISP is licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted.

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