When discussing different sources of energy, you often hear the terms “renewable” and “non-renewable”. What is the difference? Quite simply, a renewable energy source like solar, wind, hydro, geothermal, biomass, ocean is one that can be replenished in a human’s lifetime. Non-renewable sources such as fossil fuels (coal, oil, natural gas) will technically replenish, but over many, many, thousands of years meaning we use them up much faster than they are produced. Here in this article, we will learn about different renewable and non-renewable energy resources.
Some solutions are relatively simple and would provide economic benefits: implementing measures to conserve energy, putting a price on carbon through taxes and cap-and-trade and shifting from fossil fuels to clean and renewable energy sources.
– David Suzuki
We will talk a little bit about the pros and cons of some of the different kinds of energy starting with the more familiar non-renewable sources.
Coal is one of the oldest and most plentiful forms of non-renewable energy used by humans. It is relatively cheap, provides a high amount of energy in relation to its weight. However it is also one of the dirtiest forms of fossil fuels and mining it is fairly dangerous.
- Plentiful: Especially within the United States. Cost to use is lower than other forms of energy.
- Fairly Efficient: Out of the potential energy present in coal, a high percentage of it is utilized when coal is burned.
- Safe Power Plants: Compared to nuclear power, coal plants are much safer.
- Relatively Cheap: It is a mature industry, and relatively cheap source of energy to set up.
- Dirty: Out of all the fossil fuels, coal burns the dirtiest. Burning it releases high levels of carbon dioxide into the atmosphere. Coal plants also release dangerous levels of mercury and arsenic. Local pollution around coal plants are a problem.
- Dangerous to Mine: Coal mining is a very dangerous job. In addition, mining has negative environmental effects, including flooding, increased erosion, and release of methane gasses.
- Highest Energy Output Likely Reached: While efficient, the maximum potential has likely already been reached in energy available to draw from coal compared to other technologies that have potential for increased efficiency.
- Finite Source : While currently plentiful compared to other sources of energy, it is a limited supply likely to be exhausted within a couple centuries unless other alternatives are explored.
Very widely used worldwide for fuel and even in non energy uses like creating plastics. Not as common for power plants, but is a very common fuel source for transportation like automobiles, airplanes, boats and trains.
- Well Developed Infrastructure: Many countries produce and refine oil, and global distribution is already in place. Gas stations to refuel personal vehicles are plentiful, compared to a more limited infrastructure like recharging stations for electric vehicles.
- Easy to Transport: Being a liquid it can be transported through pipelines meaning a large amount of oil can be transported long distances relatively quickly.
- Efficient: According to the U.S. Energy Commission, no other kind of fuel contains as much energy per unit of volume as diesel and gasoline does.
- Dangerous to Environment: Like coal, burning oil releases carbon dioxide into the atmosphere in addition to nitrous oxide and methane. Spills at drill sites or pipelines also cause negative effects to the surrounding environment and wildlife.
- Limited Supply: Like all fossil fuels, it takes potentially millions of years to produce more. The demand for oil is so high, that based off currently known oil deposits in 2013, the U.S. Energy Commission estimates we will deplete our supplies by approximately 2063.
Primarily composed of methane, Natural gas can be used for heating, cooking and generating electricity.
- Cleanest of Fossil Fuels : Burning natural gas releases 45% less CO2 than coal and 30% less than petroleum. It also leaves almost no waste like ash or other residues after being burned.
- Easy to Transport: Can be sent via pipeline to homes for heating and cooking. A well established network of pipelines exist.
- Cheap: Cheaper than other fossil fuels. In addition gas appliances in the home tend to be cheaper than their electric counterparts.
- Toxic & Flammable: Natural gas is very flammable and potentially explosive, making leaks problematic. It is also dangerously toxic to inhale and completely odorless in its natural state. Chemicals are added to give it a distinctive offensive smell, but leaks deep underground can potentially go unnoticed as those chemicals dissipate and lose strength.
- Needs More Processing: In order to be usable as a fuel, natural gas requires more processing compared to coal or oil. The process of refining it creates several byproducts like sulfur, hydrocarbons, water vapor, CO2 and nitrogen.
- Non-renewable: Like all fossil fuels, we are using it faster than more is being created making it unsustainable in the long term, even if currently we have an abundance.
Moving into renewable energy sources we will start out with solar power. Basically the idea is that solar cells capture sunlight, convert it into electricity and that get stored in batteries for use later.
More from solar energy:
- Advantages of Solar Energy
- Disadvantages of Solar Energy
- Pros and Cons of Solar Energy
- Facts of Solar Energy
- Environmentally Friendly: Capturing sunlight and converting it into energy does not generate any air or noise pollution.
- Sustainable: As long as the sun comes up, more energy will be produced. It is impossible for future generations to be deprived of the resource since we can’t use it up.
- Abundant Source: The energy potential from the sun is staggering if we were able to harness all of it. The surface of the earth is bathed with enough solar energy in one hour to meet the energy needs of the entire planet for a year, if we were able to somehow capture all of it.
- Great Choice for Remote Locations: Often cheaper to set up solar than run high voltage lines to remote areas off the power grid.
- Expensive to Set up: Initial setup cost is the largest con for solar energy. Some states will provide tax credits or other subsidies to try and help offset the cost, but it is still one of the more expensive alternatives to set up.
- Efficiency Affected by Environmental Factors : Besides the obvious drawback of only producing energy during the day, the efficiency of solar cells can be negatively affected by cloudy days or excessive pollution.
- Space Required : Large scale solar plants currently require wide areas of open land to produce power levels comparable to a traditional power plant. Technology to increase efficiency is always improving though.
Humans have harnessed the power of wind for centuries, from windmills to grind grain to sailboats used to travel across the oceans. These days large wind turbines can be used to create electricity.
- Clean Source: Using wind power does not generate any air pollution like fossil fuels do.
- Renewable: You can’t deplete the earth’s source of wind. It will continue to blow whether or not we harness it, and harnessing it does not reduce its supply in any way.
- Inconsistent Source: Wind direction and strength can be unpredictable and inconsistent, making wind as a primary energy source non viable .
- Noisy: Wind turbines are not silent, and usually produce around 50-60 decibels of noise with their use. People living near wind turbines often complain about the noise they create. This disadvantage is reduced by building wind farms offshore or in remote, rural areas.
- Aesthetics: Since wind turbines are located typically in rural areas, many people think of them as a blight on the otherwise untainted landscape.
- Danger to Wildlife: Wind turbines can be dangerous to birds or bats in the area. Especially in they are located in migration paths.
Geothermal energy is getting more and more attention these days. Many new construction plans call for its incorporation. Using the heating and cooling energies in the Earth in a cyclical system, geothermal is both a renewable energy source – but it has its drawbacks too.
- Clean energy source: Geothermal energy does not have a high rate of pollution and is considered to be environmentally friendly.
- Renewable: The Earth’s heat is replenished naturally so there isn’t a chance you could exhaust the supply.
- Effective Potential: It is estimated that Geothermal energy could be produced in many areas of the world and provide up to 2 terawatts of energy per year.
- Meets Base Load Need: This is a far more reliable way to meet the base load need of a population and area than other forms of clean energy.
- Scalable: This solution can work as well for a small house as it will for a manufacturing facility.
- Small Footprint: It doesn’t take much land to create a geothermal plant, and there is little pollution created from constructing a system.
- Innovation Investment: Much money is being invested in researching innovations for this technology, meaning it will lower the overall costs of the energy and allow more resource areas to be used.
- Environmental Concerns: While geothermal creates very little environmental impact, there are still some concerns about what impact it does create.
- Vulnerable in Certain Areas: Areas prone to earthquakes or other seismic activity are not ideal for geothermal power plants.
- Heavy Costs up Front: Constructing the power plant and the heating and cooling system costs more upfront than other types of renewable energy.
- Location Specific: You can’t create a resource draw as you can with hydro power which means placement of a plant is limited to the resource access.
- Managed Renewal: Geothermal resources have to be managed or they can run dry.
Biomass energy uses the natural process of photosynthesis and other biological energy production that occurs with organic subjects.
- Renewable: If you can grow it, it can be used in biomass energy production. This makes it a highly renewable source.
- Carbon Neutral: This is one of the few forms of energy that is considered to be carbon neutral. It does have a carbon impact, but it is considered to be part of the natural carbon cycle on the planet and causes no additional burden on the atmosphere.
- Cost-Effective: Compared to the fossil fuels, biomass energy is almost 1/3 cheaper to produce. Over 10 to 15 years of use, the average user will see a significant savings in energy cost.
- Abundant: Wherever you can grow you can create biomass energy. There is no need for extra transport such as pipelines to deliver it to areas.
- Expensive: This can be one of the more expensive energies to produce as it is dependent on a growing and harvesting cycle.
- Extensive Footprint: While new technologies are being developed to allow for plants to used smaller spaces, right now extensive space is needed to grow enough of the biomass to produce energy.
- Resource Drain: Growing requires water and that can be a problem in some areas of the world and would limit the effectiveness of biomass energy production.
Hydro power harnesses the power of water flow to generate electricity by using the flow to turn turbines. In many ways this is one of the cleanest technologies, but it also has a cost that has to be considered.
- Reliable: Compared to the other “clean” powers such as geothermal, solar and wind; hydro power is far more reliable as the water is more predictable in its amounts and delivery.
- Clean: Using hydro power reduces the need to burn fossil fuels. The output from the plant also has a very light carbon and air pollutant emission rate.
- Cost Effective: While costly to build and having a high maintenance budget, the long term cost of a hydro power system is much cheaper than traditional power plants.
- Renewable: Water exists on the Earth and in the atmosphere. It is constantly renewing itself so this makes hydro power a renewable energy source.
- Multipurpose Raw Material: If you view water as a raw material, and the reservoir as the holder for that material than you can see that there are multiple uses for the water at the same time it is used for power. It can host wildlife, irrigate farmland, provide drinking water and be a point of recreational activities for the community.
- Marine Life Endangerment: While building a dam creates a reservoir that becomes a marine habitat, it only does so by destroying the natural one that exists. This can interrupt the ecology of the area. Also, the turbines used by the power plant can hurt the fish population by changing the currents in the water and interrupting feeding and spawning patterns.
- Natural Occurrences: This is the term used to describe such factors as drought that can change the expected capacity of a hydro power plant. As of yet, there is little man can do to control certain natural occurrences that can reduce the plants output.
- Implementation and Maintenance Cost: Hydro power plants are very expensive to build, and they also have a high maintenance cost. Unlike other types of power that are contained within a plant, hydro power must also care for off site entities such as dams, reservoirs and river systems.
- Imminent Danger to Human Populations: Dams can break, flash floods can occur and all sorts of problems can put the human population in the surrounding area of a hydro plant in danger.
Now that you know the pros and cons of the different renewable and non-renewable energy sources you can see what a complex subject this is. It isn’t always a case that cleaner is better, careful consideration has to be given to all the potential energy sources and the best one chosen. That best one has to meet cost, safety and ecological needs.