The world's search for renewable energy sources has led to some interesting discoveries. Each source has its own strengths and weaknesses, but there are more options available than you might think. Here are a few of them.

1. Solar Energy

This is one of the most common types of renewable energy, since individuals can implement it in their own homes via solar panels. These panels convert sunlight into electricity, powering whatever they're hooked up to. One of the attractive features of solar power is that there is no limit to the sunlight that creates it, especially when the system is able to store energy during the night and during cloudy days. For individuals, though, these panels can be expensive to set up, and they require specific placement where they can receive sunlight all day, so many homes aren't conducive to them. When they are in use, though, they can save individuals and businesses money on their energy bills and can even feed electricity back into the grid, making them money. Solar panels also cut down on the need for fossil fuels, making them an attractive alternative energy source.

2. Wind Energy

If you've ever driven through Midwestern states such as Kansas or Nebraska, chances are you've seen a wind farm or two. The giant, white wind turbines that comprise these wind farms are pumping electricity into a nearby facility or a utilities grid. Wind, like sunlight, is also an unlimited resource, but it isn't usually feasible to put massive windmills near the large cities that need the most power. These machines may look graceful, but they do create a good amount of noise, and you need quite a few of them in order to produce usable electricity. As a result, the wind farms need to be in areas such as a field in the middle of Kansas or in the ocean-both places that have almost constant wind and a low number of nearby people. The energy then must be transported to the areas that need powering, which can get expensive. However, wind energy is a renewable energy source that can be used to supplement the need for fossil fuels and even replace them in some areas. Plus, they need to be designed, installed and maintained, which means they create jobs.

3. Hydroelectric Energy

Hydroelectric energy is energy produced by moving water. Many dams accomplish this by guiding the large amounts of water behind them through small spaces with turbines in them to produce electricity. Smaller turbines and dams can also do this on smaller bodies of water. Hydroelectric energy produces little to no pollution, making it an attractive energy source. There are downsides, however. These facilities don't produce much power and sometimes even take more energy to pump the water through the turbines than they produce. In addition, some dams can drastically change the flow of rivers and the ecosystems within them. But, the fact that the movement of water isn't going to go away any time soon, combined with hydroelectric energy being an incredibly clean energy source, makes it a promising alternative energy source to continue pursuing.

4. Geothermal Energy

The earth has large amounts of heat trapped under its surface, and it escapes occasionally through volcanoes, geysers, and hot springs. People have begun to discover ways to harness this energy into a renewable source. It's not as common as sunlight, wind, or water, but it is powerful. The facilities that convert this power into usable energy can also be built underground, cutting down on the damage done to land. There are downsides to this energy source, though, which is why it isn't more commonly used. Building the geothermal energy facilities is expensive, and they're often vulnerable to earthquake damage. However, this source has a lot of potential in the pursuit of renewable energy.

Clean and renewable energy sources, like anything, bring both pros and cons. They do bring potential, however, to the search for energy that doesn't harm the planet.