To qualify as renewable energy, power needs to be derived from natural resources of the earth that are not exhaustible. The field has been developed as an alternative to fossil fuels due to the impact that mining and burning these fuels has on the environment, not to mention the fact that one day the earth will run out of this finite resource.
By exploring different means of producing energy, the hope is to produce inexpensive energy that is not finite and can meet the growing needs of the human population without causing pollution. Over the years, several forms of renewable energy have been explored and developed. Each of these different forms of energy has benefits and drawbacks that must be considered.
Farms that harness wind energy use large turbines to convert currents in the air into electricity. There are many different systems for converting wind energy to electricity. Commercial wind farms can generate a substantial amount of energy, but even single turbines can help offset other forms of power. Wind is a very clean source of energy and has no environmental or health effects. Plus, wind farms help create many jobs.
The primary downside of wind energy is that the turbines tend to be in rural areas away from cities, which is where energy demands are highest and the transportation of energy results in higher costs. Also, turbines can produce noise and dominate skylines.
Radiant energy from the sun can be captured directly and converted into electricity. Today, systems use photovoltaic cells that easily perform this conversion.
Because it is so readily available, sunlight is a functionally endless source of power that could completely replace fossil fuels. Many federal and local government agencies have created programs to incentivize investment in solar energy.
The primary hurdle to adopting solar power, however, is the high upfront cost. The technology will likely save money in the long run, but it requires a significant investment that is unrealistic for many households. Also, homes need to be in sunny locations with ample space for installing solar panels to make the technology accessible on the individual level.
Most hydroelectric power comes from dams. Water flows through turbines, moving them to produce electricity. Both large-scale and small-scale projects have been successfully implemented to produce hydroelectric power, which itself does not generate any sort of pollution. However, many of these facilities end up using more energy than they produce as fossil fuels are typically burned to pump water as part of the storage system. Also, disrupting waterways can have an impact on the animals that live in those ecosystems and change the overall levels of water, which alters currents and migration paths for fish. Moving forward, it could be possible to create more efficient systems that are less disruptive, but more work needs to be done.
The concept of using hydrogen for power has gained some momentum in the past few years. Hydrogen has unique chemical properties that make it effective as a fuel. In fact, hydrogen has been made into a clean-burning fuel that produces much less pollution than gasoline or diesel. Perhaps more importantly, fuel cells that are similar to batteries make it possible to convert this fuel into power.
The primary hurdle to adopting this technology is that hydrogen energy needs to be produced, and this process currently relies on fossil fuels. Thus, while the fuel itself is clean, the process of making it is not. More time and energy will need to be invested in infrastructure before this technology is efficient.
Bioenergy refers to energy from biomass, which is organic matter from formerly living plants and organisms. While the concept may sound foreign, burning wood in a fireplace is a perfect example of biomass. Energy can be generated through biomass through burning or even just harnessing the methane gas that is naturally released as part of the decomposition process.
While burning biomass produces carbon dioxide, replacement plants consume the same amount of carbon dioxide, creating a balance. However, plants take considerable time to grow, so the balance is not immediate. Also, no infrastructure currently exists for reliably using biomass in place of fossil fuels.
Heat gets trapped under the surface of the earth from both radioactive decay and processes related to the original formation of the earth. This heat can naturally escape through geysers and volcanic eruptions. However, the heat can also be captured to produce geothermal energy.
Geothermal plants can be built underground, leaving only a small footprint on the land. Plus, the source is naturally replenished. Moving forward, geothermal energy could be a significant source of renewable power, but the cost of creating infrastructure is very high. Thus, it may take a lot of time to get to the point of commercial production. Also, the infrastructure would be very vulnerable to earthquakes.