It is commonly accepted among scientists that human activity causes climate change and that a substantial amount of carbon is emitted into the atmosphere through fossil fuel combustion and animal husbandry. As a result, the climate is becoming more erratic. The global temperature is rising, extreme weather conditions are appearing more frequently, and glaciers and other frozen bodies of water are steadily melting. In 2018, over 400 million electric cars were sold worldwide and the demand remains high.
These vehicles are dependent on fossil fuels to power their motors and every year, more and more people are reducing their dependence on oil-generated power. Therefore, alternative energy sources are becoming more valuable and sought after. One such source is solar energy, which is clean, abundant, and readily available.
When connected to a battery, solar energy can be stored and used later when the sun isn’t directly above it. Because it is clean and sustainable, more and more people are turning to solar energy instead of conventional power generation methods. The following paragraphs will examine the potential of solar energy and how to make the most of it.
Types of Solar Energy
Broadly speaking, solar energy can be classified into three categories: diffuse solar energy, direct solar energy, and concentrated solar energy.
Diffuse solar energy, sometimes referred to as “skylight” energy, is radiated into the atmosphere by the sun. While a portion of this energy will be reflected back toward the earth, the majority will pass right through the atmosphere and affect the climate of planet earth. Diffuse solar energy is most effective at raising the temperature of the air near the surface, so it is most useful for space heating and water heating. Since it is clean and sustainable, many large buildings with large skylights have been constructed in recent years, particularly in the southern part of the country. Due to its diffuse nature, diffuse solar energy requires a large surface area to collect enough energy to make a noticeable impact on the environment.
Direct Solar Energy
Direct solar energy, sometimes referred to as “sunlight” energy, is radiated directly into the atmosphere by the sun. Like diffuse solar energy, the direct solar energy reaching the earth is radiated into the atmosphere and affected by the atmosphere, however, its major impact isn’t felt locally, but globally. Due to its direct impact, the temperature of the air near the surface will rise quickly when exposed to direct solar energy, resulting in a short-lived but noticeable increase in the local climate. Because it doesn’t rely on atmospheric conditions to be radiated into the atmosphere, direct solar energy can be captured and stored for later use.
Concentrated Solar Energy
Concentrated solar energy, sometimes referred to as “solar heat” or “solar electricity,” is similar to direct solar energy but can be gathered and sent to locations that need it. The most familiar example of concentrated solar energy is probably solar thermal energy, which is used to generate electricity via heat. However, many different types of concentrated solar energy exist, including but not limited to:
- Photovoltaic energy (PV)
- Solar hot water heating (SHWH)
- Solar power tower (SPT)
- Solar furnace (SF)
- Solar drying (SDr)
- Solar trackers (ST)
- Thermal solar power (TSP)
- And more
You’ll notice that many of these technologies are used to generate electricity, however, this is only because electricity is the most widely understood and accepted application of concentrated solar energy. In reality, there are many different ways that this abundant and sustainable energy can be used.
For example, thermal solar power is particularly useful for heating and cooling, especially in the summer and winter, respectively. It can be used to generate hot water for use in homes or businesses, or it can be stored in a large tank and used later when needed.
Photovoltaic energy is another type of concentrated solar energy that can be used to generate electricity. The most familiar form of photovoltaic energy is most likely the solar cell that you’ve seen advertised on televisions and other large screens.
These devices allow for the conversion of sunlight into electricity and have several different varieties, including but not limited to:
- Monocrystalline silicon (mono-Si)
- Polycrystalline silicon (poly-Si)
- Enhanced cadmium telluride (CdTe)
- And more
Depending on the location and time of day, the rays of the sun will either be reflected back toward the earth or absorbed by the atmosphere. As a result, the area directly above any given point on the earth will either be too cold or hot for comfort, depending on the time of year and geographic location.
When choosing an energy source to power your home or business, it is important to consider the type of climate you are trying to create and the time of day that you’ll be using the unit. In regards to the former, if you are looking to heat your home or office during the winter months, thermal solar power, heat pumps, and hot water storage are a few examples of energy sources that can help. In regards to the latter, if you are looking for a renewable energy source to power your home or business, then photovoltaic energy, thermal solar power, and heat pumps are candidates.
How Can Solar Energy Work For You?
If you’ve decided that solar energy is a viable option for your home or business, the next step is to determine how you will use it to benefit your everyday life. A rough guideline is to look at how much energy you need and how much time you have to spend collecting it. The more sunshine there is, the more energy you’ll be able to collect.
For example, if you live in a colder climate and have a lot of direct sunlight during the day, then photovoltaic energy is the clear choice. It is also one of the most efficient and popular forms of solar energy. The drawback is that it’s relatively expensive to install and maintain, particularly in colder climates. If you live in a warmer climate and have less direct sunlight or if you’re looking for an alternative energy source to supplement your existing one, then thermal solar power and heat pumps are viable options. Additionally, if you have a lot of shade where you live, then you might want to consider direct solar energy or concentrated solar energy as a source of renewable energy.
At this point, it is important to remember that just because a form of energy is renewable doesn’t mean that it is free. In fact, in a small number of cases, the cost of solar energy has risen considerably faster than the cost of conventional power generation due to decreasing production and increasing demand.
Cost Of Solar Energy
As with any other type of energy, the cost of solar energy depends on several factors. Among them are the following:
- The price of crude oil/fossil fuels
- The price of imported materials
- The efficiency of the device
- The quantity of energy needed
- The geographic location
- The time of day (shade vs no shade)
- The type of climate (temperate, tropical, or polar)
In the United States, the cost of solar energy has decreased significantly in recent years as a direct result of increased demand and decreased production. This is largely due to the fact that more people are looking to reduce their energy bills and switch to renewable energy sources. In 2017, the cost of solar energy was about $16/watt and this dropped to only $13.34/watt in 2018. The price isn’t expected to decline much further, as the cost of sun-tracking equipment and installation has largely been borne by the developer and less so by the end user.